Search

Carcasses of wild mammals provide convenient samples for wildlife disease investigators. Specifically, antibodies can persist in the blood and tissues of animals up to a few days after death and can provide information on exposure to specific pathogens, including microorganisms with zoonotic implications, such as Toxoplasma gondii, Trichinella spp., Brucella spp., and Mycobacterium spp. Although screening samples from decaying wildlife for antibodies is not a new method, an overview of the literature with clear recommendations on best practices is lacking. Here, we present results from a systematic review of 115 studies using enzyme‐linked immunosorbent assay (ELISA) to detect pathogen antibodies in wild mammals across 298 individual research projects. We discuss the range of mammalian hosts and the pathogens most represented in the literature and suggest improvements to consider when using samples from decaying animals for seroinvestigation. Our results indicate that the most examined mammals were artiodactyl ungulates and that antibodies against the bacteria Brucella spp. are those most examined to date, followed by the protozoan Toxoplasma gondii, malignant catarrhal fever virus, Schmallenberg orthobunyavirus, and the coccidian Neospora caninum. The effect of haemolysis in serum samples on ELISA results was considered in only 3.7% of the research projects we reviewed, sample size decisions were not outlined in 83% of research projects, and half of the projects did not examine seroprevalence in different age classes. Nevertheless, these details are important for replicability and accurate interpretation of results. We highlight the benefits and limitations of detecting antibodies against pathogens in carcasses from wild mammalian groups. Wild mammals are reservoirs for a wide range of pathogens including those with zoonotic potential and investigating their carcasses can help wildlife investigators to better understand the epidemiology of many diseases with implications for wildlife, livestock, and human health. [ABSTRACT FROM AUTHOR]

Background: Yellow fever virus (YFV) and dengue virus (DENV) are among the major re-emerging arboviruses that pose a significant threat to public health. Their associated burden and prevalence can be substantially underestimated due to insufficient surveillance and inadequate diagnosis. This study aimed to determine evidence of dengue, yellow and related flaviviruses circulation among the rural human populations residing in Nguruman (Kajiado County) and Kerio Valley (Baringo County), two dryland ecosystems in the Kenyan Rift Valley. Methods: Serum samples obtained from febrile patients between 5 and 85 years through a hospital-based cross-sectional survey from July 2020 – May 2023, were screened for neutralizing antibodies to YFV, DENV-2 and related flaviviruses, West Nile virus (WNV) and Zika virus (ZIKV) via Plaque reduction neutralization test (PRNT). The study sites and important demographic characteristics were obtained using a structural questionnaire and the data analyzed and seroprevalence compared. A multinomial logistic regression model was done to predict risk for each of the most prevalent viruses with covariates; age, gender, and occupation. Results: Overall, 54.5% (50.1–59.0% 95% confidence interval (CI) of the samples tested positive for at least one of the four Flaviviruses. The percentage was significantly higher in Kerio Valley (64.34%, 184/286) than in Nguruman (40.2%, 78/194) (P<0.0001). YFV had the highest prevalence, followed by WNV (16.25%), ZIKV (5.2%), and DENV-2 (1%). Kerio Valley had a significantly higher YFV seroprevalence (51%) than Nguruman (6%) (P<0.0001), while DENV-2 was observed only in Nguruman with a low seropositivity of 2%. In contrast to Nguruman, where seropositivity rates were higher in males at 47.47% (P=0.049), in Kerio Valley, females showed considerably higher viral seropositivity at 60.82% than males (P<0001). Conclusion: The study suggests that there is significant circulation of Flaviviruses in both regions, posing a public health risk, that could potentially contribute to clinical disease. However, seropositivity rates vary for each specific site. Furthermore, there could be a risk of YFV, WNV, and ZIKV transmission in both sites with DENV transmission specifically noted in Nguruman. The study findings inform direct cost-effective actions (such as YF vaccines) and precise surveillance data of vector populations for improved disease risk prediction. [ABSTRACT FROM AUTHOR]

Background: Peste des petits ruminant (PPR) is a contagious disease caused by the peste des petits ruminants virus (PPRV). The disease poses a significant economic threat to small ruminant production in Ethiopia, particularly to the striving pastoral production system. A cross-sectional study was conducted to estimate the seroprevalence and associated risk factors of PPR in the small ruminants of the Borena Zone. A total of 384 serum samples were collected randomly from sheep and goats and examined for the presence of PPRV antibodies using competition enzyme-linked immune sorbent assay (c-ELISA). Additionally, a retrospective analysis of five years of outbreak data was performed to provide insight into the spatial and temporal distribution of the disease. Results: The seroprevalence of PPRV antibodies in nonvaccinated, vaccinated, and unknown vaccination status of small ruminants in this study was found to be 32.1%, 68.8%, and 45.5%, respectively. Multivariable logistic analysis revealed a statistically significant association between PPRV seropositivity and several factors, including age, animal origin, flock size, and veterinary services status. A retrospective analysis revealed 53 PPR outbreaks in the Borena Zone from 2018 to 2022, exacerbated by low vaccination coverage relative to the at-risk animal population. Conclusion: The study revealed significant gaps in current vaccination efforts, with herd immunity levels falling below the FAO-WOAH recommended threshold of 80%. Despite Ethiopia's ambitious goal to eradicate PPR by 2027, the frequent outbreaks and insufficient herd immunity highlight the inadequacy of the existing strategies. To effectively move toward eradication, Ethiopia must align its approach with the global PPR eradication framework, which emphasizes a comprehensive strategy that includes diagnostics, surveillance, prevention, and the establishment of a robust veterinary regulatory system, rather than relying solely on vaccination. Overcoming logistical challenges, improving vaccination coverage, and optimizing the timing of vaccination campaigns, especially in hard-to-reach areas, will be crucial for reducing outbreaks and making progress toward eradication. [ABSTRACT FROM AUTHOR]

Background: Understanding the level of exposure to Lassa virus (LASV) in at-risk communities allows for the administration of effective preventive interventions to mitigate epidemics of Lassa fever. We assessed the seroprevalence of LASV antibodies in rural and semiurban communities of two cosmopolitan cities in Nigeria with poorly understood Lassa epidemiology. Methods: A cross-sectional study was conducted in ten communities located in the Abuja Municipal Area Council (AMAC), Abuja, and Ikorodu Local Government Area (LGA), Lagos, from February 2nd to July 5th, 2022. Serum samples collected from participants were analyzed for IgG and IgM antibodies using a ReLASV® Pan-Lassa NP IgG/IgM enzyme-linked immunosorbent assay (ELISA) kit. A questionnaire administered to participants collected self-reported sociodemographic and LASV exposure information. Seroprevalence of LASV IgG/IgM was estimated overall, and by study site. Univariate and multivariate log-binomial models estimated unadjusted and adjusted prevalence ratios (aPRs) and 95% confidence intervals (CI) for site-specific risk factors for LASV seropositivity. Grouped Least Absolute Shrinkage and Selection Operator (LASSO) was used for variable selection for multivariate analysis. Results: A total of 628 participants with serum samples were included in the study. Most participants were female (434, 69%), married (459, 73%), and had a median age of 38 years (interquartile range 28–50). The overall seroprevalence was 27% (171/628), with a prevalence of 33% (126/376) in Abuja and 18% (45/252) in Lagos. Based on site-specific grouped LASSO selection, enrollment in the dry season (vs. wet; aPR, 95% CI: 1.73, 1.33–2.24), reported inconsistent washing of fruits and vegetables (aPR, 95% CI: 1.45, 1.10–1.92), and a positive malaria rapid test (aPR, 95% CI: 1.48, 1.09-2.00) were independently associated with LASV seropositivity in Abuja, whereas, only a self-reported history of rhinorrhea (PR, 95% CI: 2.21, 1.31–3.72) was independently associated with Lassa seropositivity in Lagos. Conclusions: The LASV seroprevalence was comparable to that in other areas in Nigeria. Our findings corroborate those from other studies on the importance of limiting human exposure to rodents and focusing on behavioral factors such as poor hygiene practices to reduce exposure to LASV. [ABSTRACT FROM AUTHOR]

Lyme borreliosis (LB), the most common tick‐borne disease in Europe, is endemic to southern coastal Norway. LB commonly presents as erythema migrans, which can disseminate, resulting in more severe disease such as Lyme neuroborreliosis or arthritis. In Norway, public health LB surveillance is conducted via mandatory reporting of laboratory‐confirmed disseminated cases. From 2012 to 2022, Norway's surveillance‐reported incidence of laboratory‐confirmed disseminated LB increased by 78%. Although surveillance provides estimates of the incidence of disseminated LB, this study sought to estimate the incidence of symptomatic LB to better understand Norway's LB disease burden. Two studies were identified that, when combined, estimated an LB seroprevalence of 6.8% in the general adult population in southern Norway. Utilizing data from these seroprevalence studies, public health surveillance, and results from literature searches indicating that 37% of seroconverted LB cases are symptomatic and that the duration of LB antibody detection ranges from 10 to 20 years, we estimated that there were 315–630 symptomatic LB cases per 100,000 adult population in five southern coastal counties in Norway in 2022 and 24–48 cases of symptomatic LB for every public health surveillance‐reported LB case in adults in these five counties in Norway. [ABSTRACT FROM AUTHOR]

The surveillance and detection of zoonotic pathogens in animals is essential for predicting disease transmission pathways and the risks of spillover, but challenges include the costs, ethics and technical expertise required for vertebrate trapping, serum sampling and antibody or virus screening. Surveillance using haematophagous arthropods as a sampling tool offers a unique opportunity to obtain blood samples from a wide range of vertebrate species, allowing the study of host-mosquito associations, and host exposure to pathogens. We explored vertebrate diversity and potential Ross River virus (RRV) transmission pathways by analysing blood-fed mosquitoes collected in Brisbane, Australia. Host origins were identified using barcode sequencing, and host exposure to RRV was assessed using a modified plaque reduction neutralisation test. In total, 480 blood-fed mosquitoes were collected between February 2021 and May 2022. The host origins of 346 (72%) bloodmeals were identified, with humans (73%) and cattle (9%) comprising the dominant hosts. RRV seroprevalence was high in both vertebrate species with evidence of RRV exposure in 70% (21/30) of cattle and 52% (132/253) of humans. This is a novel, non-invasive method of estimating seroprevalence in vertebrate host populations. Our results highlight the potential of blood-fed mosquitoes to provide species-specific insights into pathogen transmission dynamics. [ABSTRACT FROM AUTHOR]

Brucellosis is an important neglected bacterial zoonotic disease in sub-Saharan Africa, including Somalia. A cross-sectional study was conducted in the Garowe district, Nugal region, Somalia, from May 2022 to January 2023 to estimate the seroprevalence of small ruminant brucellosis and assess owners' knowledge, attitudes, and practices toward brucellosis. A total of 384 sheep and goats were selected using a simple random sampling technique and screened for Brucella antibodies by the Modified Rose Bengal Plate Test, and positive samples were then further confirmed using an indirect enzyme-linked immunosorbent assay. For the questionnaire survey, 384 households were selected randomly, and a structured questionnaire was used to assess owners' knowledge, attitudes, and practices toward brucellosis. The overall brucellosis seroprevalence was 4.7% in small ruminants (95% CI: 2.8-7.3), and the true seroprevalence was calculated as 5.2%. According to the multivariable logistic regression analysis, sex was found to be a potential risk factor for small ruminant brucellosis (P <.05). More specifically, female sheep and goats were 9.13 times (aOR 9.13, 95% CI: 1.18-70.33) more likely to become seropositive than males. The owners' knowledge, attitudes, and practices toward brucellosis were found to be low, and education level was associated with owners' knowledge (χ2 = 16.78; P <.001), attitudes (χ2 = 19.4; P <.001) and practices (χ2 = 34.0; P <.001). There is also a significant association between owner knowledge, attitudes, and practices and seropositivity of brucellosis in sheep and goats. Moderate seroprevalence, together with insufficient knowledge, attitudes, and practices of owners, makes brucellosis a threat to animals and the entire community. Hence, raising community awareness of the disease is essential to reduce the impact on small ruminant productivity and the risks to public health. [ABSTRACT FROM AUTHOR]

Introduction: Exposure rates to Histoplasma species, the causative agent of equine epizootic lymphangitis (EL), are unknown amongst working equids in The Gambia. The primary aims of this study were to estimate anti-Histoplasma antibody seroprevalence in the equid population in rural The Gambia and to explore risk factors for seropositivity. Methods: A nationwide cross-sectional study was conducted (February-July 2022), representing baseline measurements of a longitudinal cohort study. Horses (n = 463) and donkeys (n = 92) without EL signs were recruited in 18 study sites. Following informed owner consent, equid clinical and management data were recorded. Blood samples were collected by jugular venepuncture, and sera were subject to the IMMY Latex Agglutination Histoplasma test (LAT). Seropositivity risk factors were explored by multi-level, multivariable logistic regression analysis. Study site and household variance were described using a latent-variable approach. Whole blood DNA extractions were subject to nested ITS-PCR to detect Histoplasma capsulatum var. farciminosum (HCF), and agreement with LAT results was measured using Cohen's kappa statistic. Results: Anti-Histoplasma antibody seroprevalence in horses and donkeys was 79.9% [95% confidence interval (CI) 76.0-83.5%] and 46.7% (95% CI 36.3-57.4%), respectively. In horses, two multivariable models explained the maximum amount of data variability. Model 1 demonstrated increased odds of seropositivity in mares [odds ratio (OR) = 2.90 95% CI 1.70-4.95, p < 0.001] and decreased odds in horses <2.5 years (OR = 0.46 95% CI 0.22-0.95, p = 0.04; reference: ≥4.5 years). Model 2 demonstrated increased odds in horses recruited during the rainy season (OR = 2.03 95% CI 1.08-3.84, p = 0.03) and those owned by farmers reporting previous EL in their equids (OR = 1.87 95% CI 1.04-3.37, p = 0.04). Decreased odds were measured in horses <2.5 years (OR = 0.37 95% CI 0.18-0.78, p = 0.01) and horses reported to transport firewood (OR = 0.45 95% CI 0.28-0.74, p = 0.001). On multivariable analysis of donkeys, decreased odds of seropositivity were demonstrated amongst donkeys owned by households which also owned horses (OR = 0.23 95% CI 0.06-0.85, p = 0.03). HCF infection prevalence in horses and donkeys was 22.0% (n = 102/463, 95% CI 18.3-26.1%) and 5.4% (n = 5/92, 95% CI 1.8-12.2%), respectively. No significant agreement was measured between LAT and nested ITS-PCR results (κ < 0.00). Conclusion: High Histoplasma spp. exposure was demonstrated amongst equids in The Gambia. Investigation of risk factors, including equid husbandry and management strategies, as well as geoclimatic variations, is warranted. Outcomes may inform sustainable and equitable EL control strategies in The Gambia and comparable settings worldwide. [ABSTRACT FROM AUTHOR]

Background: Toxoplasmosis is one of the most widespread foodborne parasitic zoonoses caused by the obligate intracellular protozoan Toxoplasma gondii. Although a number of studies have reported on the seroprevalence and risk factors of T. gondii infection in ruminants in China, information about T. gondii infection in cattle in Hunan province of China is not available. Material and Methods: Sera of 985 cattle and 1147 goats were examined for the presence of specific antibodies against T. gondii using the indirect hemagglutination test. Some risk factors related to the presence of cats, herd size, gender, age, and geographical origin were determined using a binary logistic regression. Results: Specific IgG against T. gondii were detected in 8.3% (82/985) and 13.3% (153/1147) of the cattle and goats, respectively. Based on statistical analysis, the presence of cats and gender were considered important risk factors for T. gondii infection in cattle and goats in the farms in this study (P < 0.05). Conclusion: Our results provide a baseline for future prevention and control of T. gondii infection in cattle and goats in Hunan province, subtropical China. This is the first report of T. gondii seroprevalence in cattle in Hunan province, China. [ABSTRACT FROM AUTHOR]

Background: Cytomegalovirus (CMV) is the most common congenital infection in pregnancy with potential long-term adverse effects on the fetus. There is limited data on CMV seroprevalence in pregnant women in Singapore, with last reported study dating back over two decades. We look at the latest CMV seroprevalence in antenatal population in Singapore. Methods: Between January 2021 and August 2021, 385 pregnant women receiving antenatal care at Singapore General Hospital were randomly selected for CMV IgG test to be performed on their blood samples collected during the first trimester of their pregnancies. Positivity for CMV IgG represents past exposure prior to pregnancy. Results: Overall CMV seroprevalence was 71.7% (276/385) (95% CI 067, 0.76, p value < 0.001). The trend of CMV IgG positivity increased with age, 68.3% (95% CI 0.60, 0.76, p value < 0.001) in those aged 20–29, 72.5% (95% CI 0.66, 0.78, p value < 0.001) in the 30–39 age group, and 79.0% (95% CI 0.67, 0.76, p value 0.012) in women over 40. Conclusions: There is a declining trend in CMV seroprevalence among pregnant women in Singapore, which indicates that a substantial portion of this population faces the risk of primary maternal CMV infection during pregnancy. Emerging research suggests that prenatal treatment with valacyclovir effectively reduces the likelihood of vertical transmission. Considering this evidence, it is imperative to reevaluate the recommendations for universal maternal CMV screening during pregnancy. [ABSTRACT FROM AUTHOR]

Severe fever with thrombocytopenia syndrome (SFTS), a tick-borne disease caused by Dabie bandavirus (SFTSV) is an emerging infectious disease of substantial concern in East Asia. In 2019, Ongkittikul S et al. reported the first case of SFTS in Thailand. Our report describes a One Health investigation of SFTS zoonosis examining the index case and suspected animal reservoirs using real-time RT-PCR and immunoassays. We add to the report on the first confirmed case of SFTSV infection in a human in Thailand by conducting a limited but informative One Health surveillance study. Dogs and cats tested positive for SFTSV antibody using IgG ELISA. We conclude that domestic dogs and cats might serve as potential reservoirs for SFTSV spread due to their closer proximity to the index case than other non-domestic animals. Notably, we did not detect SFTSV in synanthropic cats or dogs—nor did we detect SFTSV in Rhipicephalus sanguineus ticks—using RT-PCR. We propose that One Health investigations coupling genomic and serologic assays in response to new SFTS cases could play a pivotal role in preventing and managing SFTS among humans and animals in East Asia. As such, we are establishing a collaborative response to SFTS in Thailand through human outbreak investigations that align with principles of One Health, through environmental surveys and animal RT-PCR and immunoassays. Our investigation highlights the importance of coupling RT-PCR with seroprevalence assays as principal elements of One Health surveillance for SFTS in order to shed light on potential animal reservoirs and track emerging zoonosis. [ABSTRACT FROM AUTHOR]

Leptospirosis is a worldwide re-emerging zoonotic disease. The study was conducted to estimate the Seroprevalence of canine leptospirosis in a total of 450 dogs, from a total of 97 puppies and 353 adult dogs selected for examination Sampling, started from January to December 2023 in District Kasur in the province Punjab of the country Pakistan. Leptospira IgG ELISA kit manufactured by DRG Instruments GmbH, Germany was used for the screening of canine Leptospira antibodies. Out of 450 tested dogs, 183 dogs (40.67%) were tested positive for Leptospira antibody for the screening of Leptospira antibodies. The estimated Seroprevalence of leptospirosis in various age groups of dogs, were 23.7% (23/97) and 45.3% (160/353), in puppies and adults, respectively (P < 0.05). It was found that out of the sampled dogs, a total of 35/127 (27.6%), 29/100 (29%), 73/130 (56.2%), and 46/93 (49.5%) dogs were tested seropositive for Leptospira antibodies in winter, spring, summer and fall, respectively (P < 0.05). [ABSTRACT FROM AUTHOR]

Hepatitis E virus (HEV), species Paslahepevirus balayani, poses a global public health threat, especially in developing countries, by causing acute enterically transmitted hepatitis. HEV infects various mammalian hosts and belongs to the genus Paslahepevirus in the family Hepeviridae. While swine are recognized as the main hosts of HEV, rabbits, which can also be affected by swine HEV-3 related strains, serve as the primary reservoir for the distinct emerging and zoonotic HEV-3ra subtype. In Portugal, where the European wild rabbit is abundant, their role in HEV epidemiology remains unclear. The primary aim of the present research was to evaluate the circulation and the potential for HEV infection within these species. This study employed a molecular and longitudinal serological approach to investigate HEV in Portuguese rabbits. Among the 205 wild rabbits tested, a seroprevalence of 2.44% (95% CI: 0.80–5.60) was found, with no significant associations with age, sex, localization, or sampling dates. Seropositive animals were found in the south and center regions of the country. HEV RNA was not detected in 120 fecal samples, suggesting a natural, low level, and widespread viral circulation. The study underscores the need for further research to comprehend HEV dynamics in these species, which is crucial for assessing potential transmission risks to humans. [ABSTRACT FROM AUTHOR]

Introduction Methods Results Conclusion Feline calicivirus (FCV) commonly causes upper respiratory tract, oral and ocular infections in species of the family Felidae, with high prevalence amongst domestic cat (Felis catus) populations worldwide. Detection of FCV‐specific antibodies in serum provides evidence of previous infection with FCV and an indication of whether a cat may be protected against clinical FCV disease. This study describes the most extensive sampling for anti‐FCV antibodies in feral and stray cat populations in Australia, and examines variation in prevalence associated with cat age, sex and location.Blood samples were opportunistically collected from 669 feral, stray or Indigenous community cats from the Northern Territory, South Australia, Victoria, south‐east Tasmania and south‐west New South Wales. The sera were harvested and tested for antibodies capable of neutralising the FCV vaccine strain F9 by serum‐virus neutralisation assay.Of the 669 cats tested, 69.7% had detectable FCV‐F9‐neutralising antibodies (titres ≥5). Maturity was significantly associated with higher seroprevalence and higher antibody titres, with adult cats being more than twice as likely to have detectable FCV‐neutralising antibodies than subadults. Male cats had a higher seroprevalence and slightly higher antibody titres than females. Cats living in closer proximity to humans had significantly higher seroprevalences and higher FCV‐neutralising antibody titres than feral cats from more remote regions of Australia.Australian feral and stray cats have a high risk of natural exposure to and infection with FCV, with the prevalence and levels of pre‐existing immunity to FCV being highest amongst adult cats living in highly modified urban, peri‐urban and agricultural environments. [ABSTRACT FROM AUTHOR]

Background: SARS-CoV-2, the causative agent of COVID-19, is a betacoronavirus belonging to the same genus as endemic human coronaviruses (hCoVs) OC43 and HKU1 and is distinct from alpha hCoVs 229E and NL63. In a study of adolescents in the Philippines, we evaluated seroprevalence to the hCoVs, whether pre-pandemic hCoV immunity modulated subsequent risk of SARS-CoV-2 infection, and if SARS-CoV-2 infection affected the transmission of the hCoVs. Methods: From 499 individuals screened in 2021 for SARS-CoV-2 receptor binding domain (RBD) antibodies by enzyme-linked immunosorbent assay (ELISA), we randomly selected 59 SARS-CoV-2 negative and 61 positive individuals for further serological evaluation. We measured RBD and spike antibodies to the four hCoVs and SARS-CoV-2 by ELISA in samples from the same participants collected pre-pandemic (2018–2019) and mid-pandemic (2021), before COVID-19 vaccination. Results: We observed over 72% seropositivity to the four hCoVs pre-pandemic. Binding antibodies increased with age to 229E and OC43, suggesting endemic circulation, while antibody levels was flat across ages for HKU1 and NL63. During the COVID-19 pandemic, antibodies increased significantly to the RBDs of OC43, NL63, and 229E and spikes of all four hCoVs in both SARS-CoV-2 negative and positive adolescents. Those aged 12–15 years old in 2021 had higher antibodies to RBD and spike of OC43, NL63, and 229E than adolescents the same age in 2019, further demonstrating intense transmission of the hCoVs during the pandemic. Conclusions: We observe a limited impact of the COVID-19 pandemic on endemic hCoV transmission. This study provides insight into co-circulation of hCoVs and SARS-CoV-2. [ABSTRACT FROM AUTHOR]

To effectively respond to an emerging infectious disease outbreak, policymakers need timely and accurate measures of disease prevalence in the general population. This paper presents a new methodology to estimate real-time population infection rates from non-random testing data. The approach compares how the observed positivity rate varies with the size of the tested population and applies this gradient to infer total population infections. Applying this methodology to daily testing data across U.S. states during the first wave of the COVID-19 pandemic, we estimated widespread undiagnosed COVID-19 infections. Nationwide, we found that for every identified case, there were 12 population infections. Our prevalence estimates align with results from seroprevalence surveys, alternate approaches to measuring COVID-19 infections, and total excess mortality during the first wave of the pandemic. [ABSTRACT FROM AUTHOR]

Emerging infectious diseases are a major threat to biodiversity and an important public health issue. Flaviviruses are the cause of several emerging vector-borne zoonotic arboviruses whose distribution is currently increasing in Europe. The evidence that West Nile virus (WNV) circulates in resident and migratory species has implications for both animal and public health and should therefore be studied in depth. USUTU (USUV), Bagaza (BAGV) and tick-borne encephalitis virus (TBEV) are other viruses that are beginning to spread more widely. An integrated surveillance program, namely in birds, is essential for reducing the risk of infection in human populations within the One Health principles. In the present study, wild birds admitted to wildlife rehabilitation centers in Portugal were sampled. Two hundred eight blood samples were assayed serologically for antibodies to flaviviruses by using a commercial ELISA kit. An overall seroprevalence of 19.6% (95% confidence interval [CI]: 13.7–26.7%) was observed. Antibodies against flaviviruses were detected in 13 (35.1%) different species of wild birds. Accipitriformes (26.7%; 95% CI: 18.5–36.2%) and Strigiformes (26.7%; 95% CI: 14.6–42.0%) were the orders with the highest seroprevalence rates recorded. There were no statistically significant differences (p = 0.725) between the geographical regions (NUTS II) studied, but a statistically significant difference (p = 0.017) was found between sex (male: 34.4%; female: 4.8%). A higher seroprevalence was detected in adults (32.1%) than in juvenile birds (9.3%) (p = 0.014), and age was considered a risk factor for flavivirus infection in wild birds (odds ratio 1.4; 95% CI: 0.5–4.0). More epidemiological studies are needed in Portugal since the actual spread of the genus Flavivirus throughout the country is unknown. [ABSTRACT FROM AUTHOR]

Introduction: Hantavirus infection is a zoonotic disease from rodents to humans, necessitating seroprevalence assessment for disease burden clarification and control measure implementation. This study aimed to estimate global hantaviruses seroprevalence, examining variations by regions, populations or settings. Methods: A comprehensive database search identified studies on human hantaviruses seroprevalence using IgG detection until january 2024. A random-effects meta-analysis estimated pooled seroprevalence, with subgroup analyses for geographical region, population, setting or occupation. Results: Out of 3,382 abstracts reviewed, 110 studies were selected, comprising 81,815 observations and 3207 events. The global seroprevalence was calculated at 2.93% (2.34%-3.67%). In terms of geographical distribution, our analysis encompassed 61 studies from the Americas, where the seroprevalence was estimated at 2.43% (95% CI: 1.71%—3.46%), 33 studies from Europe indicating a seroprevalence of 2.98% (95% CI: 2.19%—4.06%), 10 studies from Asia revealing a seroprevalence of 6.84% (95% CI: 3.64%—12.50%), and 6 studies from Africa demonstrating a seroprevalence of 2.21% (95% CI: 1.82%—2.71%). Subgroup analysis underscored varying seroprevalence rates across different populations, settings, and occupations, highlighting the necessity for targeted interventions and preventive measures. Conclusion: The analysis reveals a moderate global hantaviruses seroprevalence, emphasizing the viral family's complex transmission dynamics influenced by exposure and geographical factors. This highlights the need for targeted prevention and control strategies. [ABSTRACT FROM AUTHOR]

Background: Following reduction of public health and social measures concurrent with SARS-CoV-2 Omicron emergence in late 2021 in Australia, COVID-19 case notification rates rose rapidly. As rates of direct viral testing and reporting dropped, true infection rates were most likely to be underestimated. Objective: To better understand infection rates and immunity in this population, we aimed to estimate SARS-CoV-2 seroprevalence in Australians aged 0–19 years. Methods: We conducted a national cross sectional serosurvey from June 1, 2022, to August 31, 2022, in children aged 0–19 years undergoing an anesthetic procedure at eight tertiary pediatric hospitals. Participant questionnaires were administered, and blood samples tested using the Roche Elecsys Anti-SARS-CoV-2 total spike and nucleocapsid antibody assays. Spike and nucleocapsid seroprevalence adjusted for geographic and socioeconomic imbalances in the participant sample compared to the Australian population was estimated using multilevel regression and poststratification within a Bayesian framework. Results: Blood was collected from 2,046 participants (median age: 6.6 years). The overall adjusted seroprevalence of spike-antibody was 92.1% (95% credible interval (CrI) 91.0–93.3%) and nucleocapsid-antibody was 67.0% (95% CrI 64.6–69.3). In unvaccinated children spike and nucleocapsid antibody seroprevalences were 84.2% (95% CrI 81.9–86.5) and 67.1% (95%CrI 64.0–69.8), respectively. Seroprevalence was similar across geographic remoteness index and socioeconomic quintiles. Nucleocapsid antibody seroprevalence increased with age while the point seroprevalence of the spike antibody seroprevalence decreased in the first year of life and then increased to 97.8 (95% Crl 96.1–99.2) by 12–15 years of age. Conclusion: Most Australian children and adolescents aged 0–19 years, across all jurisdictions were infected with SARS-CoV-2 by August 2022, suggesting rapid and uniform spread across the population in a very short time period. High seropositivity in unvaccinated children informed COVID-19 vaccine recommendations in Australia. [ABSTRACT FROM AUTHOR]

Hepatitis C is a serious public health issue because of its chronic nature and potential to progress to cirrhosis and liver cancer, particularly among haemodialysis patients. This systematic review and meta-analysis aimed to estimate the combined prevalence of hepatitis C in these patients in Morocco. After selecting 17 studies out of 943 identified, the data were analysed using the JAMOVI software, with a random-effects model to estimate the prevalence. The overall prevalence of hepatitis C among haemodialysis patients in Morocco was estimated at 35.8% (95% CI: 26.3 to 45.3). These findings highlight the urgent need for research on the factors contributing to the spread of this infection in this population. [ABSTRACT FROM AUTHOR]

Background: Hepatitis A virus (HAV) infection is a significant global cause of viral hepatitis. At present, the anti-HAV vaccine in Italy is proposed exclusively for specific high-risk groups, and a universal vaccination program is not implemented. Objectives: This study aimed to assess the level of immunity against HAV in patients of both sexes across age groups ranging from 0 to 95 years admitted to the San Giovanni di Dio e Ruggi d'Aragona Hospital in Salerno, Italy, over a 9-year period (2015–2023). Methods: The total HAV seroprevalence by chemiluminescence Vitros system immunodiagnostics (ortho-diagnostics) was obtained by database analysis, stratifying patients for gender and age group in both the pre-pandemic (2015–2019) and pandemic (2020–2023) periods. Results: Out of 28,104 samples collected in 2015–2023, 20,613 resulted positive by total HAV immune screening, with a significant reduction in the annualized proportion of events during the pandemic period compared to the pre-pandemic period. HAV was more abundant in males than females in both periods (exceeding the 70%), with a statistically significant decrease in HAV in females in 2015–2019. The 61–70-year-old age group is more susceptible for both genders, with a strong deviation from the 41–50-year-old age group compared to the 51–60-year-old group. The pandemic period affected the number of analyzed samples in 2020. Conclusions: The study revealed high HAV seroprevalence, especially in males and individuals aged 61–70 years. There was a notable decrease in seroprevalence during the pandemic compared to pre-pandemic years. These results emphasize the need for ongoing monitoring and suggest that a universal vaccination program could address regional immunity gaps and lower disease incidence. [ABSTRACT FROM AUTHOR]

Background and Aims Methods Results Conclusions Although the evidence is uncertain, existing estimates for hepatitis C virus (HCV) in sub‐Saharan Africa (SSA) indicate a high burden. We estimated HCV seroprevalence and viraemic prevalence among the general population in SSA.We searched Medline, Embase, Web of Science, APA PsycINFO, and World Health Organization Africa Index Medicus for community‐based studies. Study quality was assessed using the Joanna Briggs Institute critical appraisal tool, and heterogeneity using the index of heterogeneity (I2). Two approaches were deployed. First, we used random‐effects meta‐analysis to pool prevalence. Second, to derive representative estimates, we weighted each country's HCV seroprevalence using 2021 United Nations country population sizes.We synthesized 130 studies. Overall, SSA HCV seroprevalence from the random‐effects model was 4.17% (95% confidence interval [CI]: 3.71–4.66, I2 = 99.30%). There were no differences between males (4.31%) and females (4.03%). Seroprevalence was 2.25%, 3.31%, and 16.23% for ages ≤20, 21–64, and ≥65 years, respectively, and was higher in rural (6.63%) versus urban (2.93%). There was indication of decrement overtime from 5.74% to 4.35% to 3.03% in the years 1984–2000, 2001–2014, and 2015–2023, respectively. The weighted overall SSA HCV seroprevalence was estimated to be 2.30% (95% CI: 1.59–3.00) with regional variation: Africa‐Southern (.79%), Africa‐Central (1.47%), Africa‐Eastern (2.71%), and Africa‐Western (2.88%). HCV viremia among HCV seropositives was 54.77% (95% CI: 47.80–61.66).HCV seroprevalence in SSA remains high. Populations aged ≥65 years, rural communities, Africa‐Western, and some countries in Africa‐Central and Africa‐Eastern appear disproportionately affected. These results underline the need for governmental commitment to achieve the 2030 global HCV elimination targets. [ABSTRACT FROM AUTHOR]

Background: Schistosomiasis is a global public health issue. In China, while the seroprevalence of Schistosomiasis japonica has currently reduced to a relatively low level, risk of infection still exists in certain areas. However, there has been a lack of comprehensive research on the long-term trends of national seroprevalence, changes across age groups, and characteristics in spatial distribution, which is crucial for effectively targeting interventions and achieving the goal of eliminating schistosomiasis by 2030. Our study aimed to address this gap by analyzing the long-term trends of Schistosomiasis japonica seroprevalence in China from 1982 to 2020 based on the data from diverse sources spanning a period of 39 years. Methodology: Seroprevalence data were collected from literature databases and national schistosomiasis surveillance system. Meta-analysis was conducted to estimate the seroprevalence. Joinpoint model was used to identify changing trend and inflection point. Inverse distance weighted interpolation was used to determine the spatial distribution of seroprevalence. Principal findings: The seroprevalence decreased from 34.8% in 1982 to 2.4% in 2020 in China. Before 2006, the seroprevalence was higher in the middle age group, and a pattern of increasing with age was observed afterwards. The areas with high seroprevalence existed in Dongting Lake, Poyang Lake, Jianghan Plain, the Anhui branch of the Yangtze River and some localized mountainous regions in Sichuan and Yunnan provinces. Conclusions/Significance: There was a significant decline in the seroprevalence of Schistosomiasis japonica from 1982 to 2020 in China. Nevertheless, schistosomiasis has not been eradicated; thus, implementing precise and personalized monitoring measures is crucial for the elimination of schistosomiasis, especially in endemic areas and with a particular focus on the elderly. Author summary: Serological immunological testing is a crucial means of monitoring schistosomiasis. In China, while the seroprevalence of Schistosomiasis japonica has currently reduced to a relatively low level, risk of infection still exists in certain areas. Achieving the goal of eliminating schistosomiasis by 2030 necessitates more precise and effective prevention and control measures. Our study intended to figure out the long-term trends of Schistosomiasis japonica seroprevalence in China from 1982 to 2020, focusing on age and spatial variations to identify high-risk areas and populations. We expect that the results can inform the development of targeted measures for schistosomiasis elimination. [ABSTRACT FROM AUTHOR]

Background: The current survey describes the seroprevalence, history of coronavirus disease 2019 (COVID-19), and vaccination status among predominantly aboriginal residents on a tourist island in southern Thailand. This information can be translated into COVID-19 vaccination and control plans for this population. Methods: We implemented questionnaire interviews and collected blood samples from 249 residents of Lipe Island, Satun Province, in January 2022. We measured the anti-nucleocapsid protein and anti-spike (anti-S) receptor-binding protein levels of immunoglobulin (Ig) M and IgG. The differences in antibody levels among participants with different histories of vaccination and infection were analyzed using one-way analysis of variance with multiple comparisons. Results: During the 2-year pandemic period, no island residents with COVID-19 required hospitalization despite the high prevalence of hypertension (33.3%) and diabetes mellitus (21.7%). Approximately 18.8% of the participants reported a history of COVID-19 diagnosis. In total, 95.1% of the participants had a history of complete vaccination, of which 93.5% were seropositive. The anti-S IgG geometric means (geometric standard deviation) were 3945.8 (2.0), 829.8 (9.7) AU/mL, 789.9 (5.3) AU/mL, and 22.7 (7.1) AU/mL, respectively, in participants with a history of both COVID-19 diagnosis and complete vaccination (group 1), incomplete vaccination and subsequent COVID-19 diagnosis (group 2), complete vaccination but no previous infection (group 3), or neither previous COVID-19 and complete vaccination (group 4). Significant pairwise differences in anti-S IgG levels were found between certain groups (1 vs 3, 1 vs 4, 2 vs 4, and 3 vs 4). Conclusions: The high coverage of vaccination, high levels of population antibody titers, variable antibody levels among completely vaccinated non-infected residents, and high prevalence of non-communicable diseases (NCDs) suggested that the local health systems could control the pandemic. However, continuing surveillance, booster vaccinations, and NCD prevention programs were still required. [ABSTRACT FROM AUTHOR]

(1) Background: early in the COVID-19 pandemic, reverse transcription polymerase chain reaction (RT-PCR) testing was limited. Assessing seroprevalence helps understand prevalence and reinfection risk. However, such data are lacking for the first epidemic wave in Belgian nursing homes. Therefore, we assessed SARS-CoV-2 seroprevalence and cumulative RT-PCR positivity in Belgian nursing homes and evaluated reinfection risk. (2) Methods: we performed a cross-sectional study in nine nursing homes in April and May 2020. Odds ratios (ORs) were calculated to compare the odds of (re)infection between seropositive and seronegative participants. (3) Results: seroprevalence was 21% (95% CI: 18–23): 22% (95% CI: 18–25) in residents and 20% (95% CI: 17–24) in staff. By 20 May 2020, cumulative RT-PCR positivity was 16% (95% CI: 13–21) in residents and 8% (95% CI: 6–12) in staff. ORs for (re)infection in seropositive (compared to seronegative) residents and staff were 0.22 (95% CI: 0.06–0.72) and 3.15 (95% CI: 1.56–6.63), respectively. (4) Conclusion: during the first wave, RT-PCR test programmes underestimated the number of COVID-19 cases. The reinfection rate in residents was 3%, indicating protection, while it was 21% in staff, potentially due to less cautious health behaviour. Future outbreaks should use both RT-PCR and serological testing for complementary insights into transmission dynamics. [ABSTRACT FROM AUTHOR]

Hepatitis C virus (HCV) infection is among the leading causes of cirrhosis and hepatocellular carcinoma. Knowledge of its prevalence and risk factors can help to effectively fight the virus. This study was the first to investigate the seroprevalence of HCV, its genotypes, and factors associated with it among the general adult population of Armenia selected countrywide via cluster sampling. Anti-HCV antibodies were detected using third-generation immunoassay. Polymerase chain reaction and genotyping was performed among anti-HCV-positive individuals. Shortly after testing, the participants underwent a telephone survey. Logistic regression models were fitted to identify factors associated with anti-HCV antibody positivity and chronic HCV infection. The prevalence of anti-HCV antibodies among 3831 tested individuals was 2% (99% CI 1.4, 2.5), and chronic HCV infection was 0.7% (99% CI 0.4, 1.0), with genotypes 3 and 2 being the most common. The risk factors for chronic HCV infection included self-reported chronic liver disease (95% CI 1.47, 15.28), having tattoos (95% CI 1.34, 10.94), ever smoking (95% CI 1.16, 9.18), and testing positive for hepatitis B virus core antibody (95% CI 1.02, 7.17). These risk factors demonstrate that there could be room for strengthening infection control measures to prevent the transmission of HCV in Armenia. [ABSTRACT FROM AUTHOR]

Background: Seroprevalence studies have proven to be an important tool in tracking the progression of the coronavirus disease 2019 (COVID‐19) pandemic. The aim of this study was to measure the seroprevalence of antibodies to severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) in the general population of Kosovo by gender, age group and region and among asymptomatic people. Method: The Institute of Public Health of Kosovo conducted a cross‐sectional population‐based survey, aligned with the protocols of the WHO Unity Studies, from the beginning of May to the end of June 2021. Results: The survey covered a total of 2204 people with a response rate of 91.8% (41.9% [923] males and 51.2% [1281] females). In May to June 2021, the prevalence of antibodies in the overall population (IgG antibodies ≥ 1.1) was 37.0%. Seroprevalence was 34.4% in men and 38.9% in women (p < 0.05), with the highest percentage (48.7%) found in the 60–69 years' age group. The overall prevalence of acute IgM antibodies (IgM ≥ 1.1) was 1% (95% CI: 0.7%–1.5%), with no significant difference between genders and the highest prevalence among participants of 60–69 years of age (1.6%; 95% CI: 0.7%–3.6%). Conclusion: A high prevalence of antibodies against SARS‐CoV‐2 was found in Kosovo before the start of the vaccination campaign. However, the results of the survey suggested that, by the end of June 2021, a desirable level of protection from the SARS‐CoV‐2 virus had not been reached. [ABSTRACT FROM AUTHOR]

Toxoplasmosis is a common cosmopolitan parasitic zoonosis caused by Toxoplasma gondii. Most often asymptomatic, toxoplasmosis can be serious for the foetus if it occurs during pregnancy. The objective of this study was to estimate the seroprevalence of toxoplasmosis among female students to contribute to the knowledge of the epidemiology of this disease. We conducted a cross-sectional study on female medical students in Bouake. The students were included after obtaining informed consent and were interviewed about their socio-demographic characteristics, gynaeco-obstetric history, factors favouring toxoplasmosis, and blood samples were collected. The samples were analysed by ELISA at the Bouake University Hospital laboratory. The collected data were entered and analysed using Word, Excel 2013, and Epi Info 7. The 168 female students included had an average age of 24 years, were married (6%), had a history of pregnancy (23.8%), were nulliparous (91.7%), had a cat (39.3%), and ate undercooked meat (72%). An overall seroprevalence of 67.9% was observed, of which 66.7% was IgG and 3.6% IgM. There was a statistically significant relationship between anti-toxoplasma seropositivity, age and the presence of a cat in the family. The overall seroprevalence of toxoplasmosis among female students at the Bouake Medical Sciences training and research unit was high. Therefore, students whose serology was negative should be made aware of the need to have a check-up in the event of pregnancy, so that appropriate measures can be taken as soon as possible. [ABSTRACT FROM AUTHOR]

Background: Equine herpesvirus (EHV) can cause respiratory, reproductive and neurological diseases in equine animals, including donkeys. The main pathogens responsible for these diseases are EHV type 1 (EHV‐1) and EHV‐4. In this study, we collected serum samples from 230 donkeys on 27 large‐scale donkey farms to detect EHV‐1 and EHV‐4 antibodies. We analyzed the presence of EHV antibodies based on region, age and season. Results: Out of the 27 farms, 62.96% (17/27) tested positive for EHV. Of the 230 donkeys tested, 2.61% (6/230) were positive only for EHV‐1, 5.22% (12/230) were positive only for EHV‐4, and 4.78% (11/230) were positive for both EHV‐1 and EHV‐4. The highest percentage of positive donkeys (21.28%) was found in Dong'e County. The seropositivity rate among donkeys aged 1–4 years was significantly higher compared to the group of donkeys aged 0–1 year (p < 0.05). Additionally, the positive rate was significantly higher in fall and winter compared to spring and summer (p < 0.05). Conclusions: Altogether, our findings indicate that large‐scale donkey farms in the Liaocheng area have a high prevalence of EHV antibodies. Since Liaocheng is an important donkey trading market in Shandong Province, it is crucial to consider the risk of disease transmission based on our test results. This will help in early detection and prevention of EHV outbreaks. [ABSTRACT FROM AUTHOR]

Background: Infectious bursal disease (IBD) is a viral infectious disease that affects young chicks. A cross‐sectional study was conducted from October 2020 to June 2021 to determine seroprevalence and associated risk factors of IBD on backyard chickens of purposively selected three districts of Buno Bedelle Zone, Southwestern Ethiopia. Methods: The study was carried out via a collection of serum samples, questionnaire surveys, and a total of 768 serum samples were collected from randomly selected backyard chickens of the study areas and examined for the presence of IBD virus. These serum samples were processed by using an indirect enzyme‐linked immunosorbent assay test procedure in laboratories. SPSS version 20 was used for data analysis and descriptive statics techniques were used. Results: Out of a total serum samples collected, 361 of them were found positive for the disease with an overall seroprevalence of 47%. Different seroprevalence rates of IBD with 55.9%, 43.3% and 41.2% were recorded in Didessa, Chora and Gechi districts, respectively. The result indicated that there was statistically significant difference (p < 0.05) of the disease among the three districts. Among the nine Peasant Associations (PAs) observed for seroprevalence of IBD, highest (62.9%) and lowest (34.20%) seroprevalence of the disease was recorded in Yembero and Shengela PAs, respectively. However, IBD was statistically significant in only Shengela PA of Chora district (p = 0.04, OR = 1.93 and 95% CI 1.04–3.58) and Seko PA of Gechi district (p = 0.05, OR = 1.79 and 95% CI 1.01–3.16). Even though sex, breed, age, source and management‐based seroprevalence was observed in the present study, the result indicated that there was only statistical significant difference (p = 0.004, OR = 0.62 and 95% CI 0.45–0.86) seen in which higher seroprevalence of IBD was determined in exotic (50.3%) than in local (38.6%) chickens breeds of the study areas. Conclusion: Generally, higher seroprevalence of IBD in the present study indicates a widely distribution of the disease and one of the potential threats for poultry production in the study areas. So, chicken vaccination and improved management system should be warranted in order to control the disease effectively. [ABSTRACT FROM AUTHOR]

Background: People experiencing homelessness are at greater risk of exposure and poor health outcomes from COVID-19. However, little data exist on the prevalence and correlates of COVID-19 among homeless populations. Tomitigate the spread and severity, uptake of the COVID-19 vaccine is needed. This can be challenging among youth experiencing homelessness who are more likely to be unvaccinated when compared to stably housed youth. Objective: We conducted this study to determine the prevalence and correlates of COVID-19 among youth experiencing homelessness. Methods: We examined experiences of COVID-19 symptoms, self-report of infection, and rates of COVID-19 antibodies and distinguished between natural and vaccinated immunity among youth experiencing homelessness (N = 265) recruited in one large metropolitan area in the south. Results: Based on self-report, very few participants experienced any symptoms, and 80%had never been diagnosed with COVID-19. Of those with COVID-19 antibodies (68%), the proportion with antibodies resulting from natural infection was 44%. The vaccination rate was 42%. Younger and vaccinated participants and those in shelters were likelier to have COVID-19 antibodies. Black and Hispanic youth were more likely than White youth to have had COVID-19. Those who adopted only one or two prevention behaviors were more likely to acquire a natural infection than those who adopted three or more prevention behaviors. Discussion: Youth experiencing homelessness report low vaccination rates, disrupted access to healthcare and social supports, and underlying chronic conditions, which may explain why they face poorer outcomes when infected with COVID-19. Vaccination and risk mitigation strategies to combat the high prevalence of COVID-19 are especially needed for sheltered youth who are at high risk yet are often asymptomatic. [ABSTRACT FROM AUTHOR]

Dengue is a highly prevalent mosquito-borne disease that is endemic in over 100 countries. It has a wider impact in terms of severity of illness and mortality risk in the absence of an effective vaccine as yet. The purpose of this study was to use meta-analysis to find out how common the dengue virus (DENV) is in India based on public data and to figure out how much of a problem. We searched, read, and reviewed about DENV in India that were available online. Forty-four cross-sectional studies were selected from the 178 records. There were reports of dengue cases in 14 out of the 28 states. Out of the patients presenting with symptoms of Dengue 27% of people were confirmed to have DENV infection with 82.29% (95% CI. 81-84%), having dengue IgM, 41.67% (95% CI: 40.16-43.43), having dengue IgG, and 23.97% (95% C.I. 14-43%), having both IgG and IgM from positive sample n=27156. Hospitalbased cross-sectional studies on suspected Dengue-like illness (DLI) found that 99.48% of people had confirmed dengue out of the patients with features of DLI, and community-based studies found that 0.52% of DLI cases had dengue. The seroprevalence rates for East, South, North, and Western regions were 35.38% (95% C.I.14-31%), 11.57% (95% C.I. 2-69%), 38.10% (95% C.I. 9-61%), and 14.87% (95% C.I. 6-38%) correspondingly. DENV is interestingly spreading across the whole country, and the disease's frequency varies a lot from place to place and from 2010-2023. However this review does not find appropriate published literature from 50% of the Indian states. The identification of IgG-class antibodies to dengue virus is indicative of prior exposure to this pathogen. Almost all immunocompetent individuals should have developed IgG antibodies against the dengue virus within three weeks of exposure. The presence of dengue virus IgM-class antibodies is indicative of an acute phase of infection. National Vector borne Disease Control Programme (NVBDCP) has some surveillance information, appropriate designed research into prevalence and risk factors for DENV infection would be required to provide adequate information for public health intervention. [ABSTRACT FROM AUTHOR]

Background: Although the diverse communities of tick-borne viruses (TBVs) have recently been proposed, the threat of infection and exposure to TBVs among humans across Kenya has been poorly understood. Objective: Severe fever with thrombocytopenia syndrome virus (SFTSV) is an emerging tick-borne viral agent associated with the epidemic of severe fever with thrombocytopenia syndrome (SFTS) disease in East Asian countries. This study investigated the seroprevalence of SFTSV among humans in Kenya. Methods: Serum samples were collected from 459 healthy people in Kenya and tested for anti-SFTSV antibodies, which were further confirmed by immunofluorescence assays. Micro neutralization assays were performed to identify neutralising antibodies against SFTSV and SFTSV-related viruses. Results: A high seroprevalence (162/459, 35.3%) of SFTSV was found in the samples from nine of the ten surveyed counties in Kenya, with higher rates in the eastern plateau forelands, semiarid and arid areas, and coastal areas than in the area aside Rift valley. The seropositive rate was slightly higher in women than in men and was significantly higher in the 55-64 age group. Neutralising activity against SFTSV was detected in four samples, resulting in a rate of 0.9%. No cross-neutralising activity against the SFTSV-related Guertu virus and Heartland virus was detected in the anti-SFTSV positive serum samples. Conclusion: The results provide serologic evidence of human exposure to SFTSV in Kenya and extend our understanding of SFTSV prevalence from Asia to Africa. The findings suggest an increasing threat of exposure to emerging TBVs and the need to investigate tick viromes in Kenya. [ABSTRACT FROM AUTHOR]

To estimate the size of COVID-19 waves using four indicators across three pandemic periods and assess potential surveillance bias. Case study using data from one region of Switzerland. We compared cases, hospitalizations, deaths, and seroprevalence during three periods including the first three pandemic waves (period 1: Feb–Oct 2020; period 2: Oct 2020-Feb 2021; period 3: Feb–Aug 2021). Data were retrieved from the Federal Office of Public Health or estimated from population-based studies. To assess potential surveillance bias, indicators were compared to a reference indicator, i.e. seroprevalence during periods 1 and 2 and hospitalizations during the period 3. Timeliness of indicators (the duration from data generation to the availability of the information to decision-makers) was also evaluated. Using seroprevalence (our reference indicator for period 1 and 2), the 2nd wave size was slightly larger (by a ratio of 1.4) than the 1st wave. Compared to seroprevalence, cases largely overestimated the 2nd wave size (2nd vs 1st wave ratio: 6.5), while hospitalizations (ratio: 2.2) and deaths (ratio: 2.9) were more suitable to compare the size of these waves. Using hospitalizations as a reference, the 3rd wave size was slightly smaller (by a ratio of 0.7) than the 2nd wave. Cases or deaths slightly underestimated the 3rd wave size (3rd vs 2nd wave ratio for cases: 0.5; for deaths: 0.4). The seroprevalence was not useful to compare the size of these waves due to high vaccination rates. Across all waves, timeliness for cases and hospitalizations was better than for deaths or seroprevalence. The usefulness of indicators for assessing the size of pandemic waves depends on the type of indicator and the period of the pandemic. [ABSTRACT FROM AUTHOR]

We identified a cluster of mpox exposures among key populations in Kenya through retrospective serologic screening. We identified strong seropositivity among sex workers and gay, bisexual, and other men who have sex with men. These findings demonstrate the need for increased mpox surveillance among mpox-endemic and mpox-endemic–adjacent regions in Africa. [ABSTRACT FROM AUTHOR]

Humans are infected by Toxoplasma gondii worldwide and its consequences may seriously affect an immune deprived population such as HIV and transplanted patients or pregnant women and foetuses. A deep knowledge of toxoplasmosis seroprevalence in Spain is needed in order to better shape health policies and educational programs. We present the results of the first systematic review and meta-analysis on the human prevalence for this disease in Spain. Databases (PubMed, Web of Science, SCOPUS and Teseo) were searched for relevant studies that were published between January 1993 and December 2023 and all population-based cross-sectional and longitudinal studies reporting the human seroprevalence in Spain were revised. Within the population analysed, our targeted groups were immunocompetent population, pregnant women and immunocompromised patients. Among 572 studies and 35 doctoral theses retrieved, 15 studies and three doctoral theses were included in the meta-analysis. A random effects model was used for the meta-analyses due to the high heterogeneity found between studies (I2: 99.97), since it is a statistically conservative model, in addition to allowing better external validity. The global pooled seroprevalence was 32.3% (95% CI 28.7–36.2%). Most of the studies carried out were in pregnant women and the meta-analysis reported that the pooled seroprevalence of toxoplasmosis in pregnant women in Spain was 24.4% (24,737/85,703, 95% CI 21.2–28.0%), based on the random effects model. It is recommended to continue monitoring the seroprevalence status of T. gondii in order to obtain essential guidelines for the prevention and control of the infection in the population. [ABSTRACT FROM AUTHOR]

Background: HEV is endemic in several Middle Eastern countries including Saudi Arabia, which hosts the annual pilgrimage for Muslims from around the world. One of the Hajj rituals is the sacrifice of animals, including camels, cows, goats, and sheep. HEV Zoonosis is established in swine and other suspected species, including deer, rabbits, dromedary, and Bactrian camels. HEV was identified in small, domesticized animals like goats, cows, sheep, and horses. We previously investigated HEV seroprevalence in Camels. This study aimed to evaluate HEV seroprevalence in other highly consumed ruminants in Saudi Arabia, namely cows, sheep, and goats. Methods: Sera from cows (n = 47), goats (n = 56), and sheep (n = 67) were analyzed for the presence of HEV-IgG by using in-house developed ELISA assays. Results: The highest seroprevalence was found in sheep (62.7%), followed by cows (38.3%), and then goats (14.3%), with a p-value of < 0.001. No other demographic characteristics of the animals were significantly correlated with the HEV seroprevalence. Conclusions: This study provides baseline data as the first study on the seroprevalence of HEV in ruminant animals in Saudi Arabia. The high seroprevalence found in sheep and cows must be further investigated for the potential zoonotic HEV transmission to humans. Further studies are needed to investigate the active viremia in these animal species through nucleic acid detection and sequencing to provide data on the circulating HEV genotypes among the targeted animal species. The detection of HEV in different animal products, such as milk, liver, and others, also remains an important study area to consider. [ABSTRACT FROM AUTHOR]

Fasciola hepatica, also known as the common liver fluke, is a globally distributed trematode parasite responsible for high economic losses in ruminants. Infection with F. hepatica occurs in Polish cattle and sheep; however, very little is known about its occurrence in goats. Therefore, a serological and coproscopic survey was carried out in Polish goats to determine the herd-level prevalence of F. hepatica infection in the goat population of Poland. Between 2014 and 2022, 33 randomly selected goat herds were serologically screened in the regions of Poland for which risk of F. hepatica infection was estimated as increased based on the spatial distribution model developed within the frame of the GLOWORM project. Virtually all adult goats (>1 year-old) were tested using a commercial MM3-SERO ELISA. Risk factors for seropositive herd status were analysed in contingency tables. Also, faecal samples from 214 goat herds monitored for gastrointestinal nematode infections and anthelmintic resistance were examined using a sedimentation method. At least one seropositive goat was detected in 11 of 33 herds, indicating herd-level seroprevalence of 33.3% (95% confidence interval (CI 95%): 19.7%–50.4%). At the animal level, only 17 of 1,464 tested goats were seropositive (1.2%, CI 95%: 0.7%–1.9%). The within-herd seroprevalence ranged from 0.8% to 11.1%. The serological status of the herd was not significantly associated with the characteristics of the herd or the extent of contact with sheep. In one herd, located in central Poland, a single positive faecal sample was found indicating a herd-level prevalence of F. hepatica infection of 0.5% (CI 95%: 0.1%–2.6%). The animal's post-mortem examination revealed liver lesions typical of chronic fasciolosis. F. hepatica infection occurs sporadically in Polish goat population and its prevalence is much lower than in cattle or sheep. Therefore, treatment or prevention of fasciolosis should only be considered if it has been reliably confirmed by an accurate diagnostic test. This applies also to goats inhabiting geographical areas where F. hepatica infection appears to be widespread in cattle and sheep, very likely due to the fact that goats avoid wet areas. [ABSTRACT FROM AUTHOR]

Historical seroprevalence data for Anisakis in Spain vary greatly depending on the sampling region owing to different fish consumption habits. As a result of European Regulation (EC) No. 853/2004, the Royal Decree 1420/2006 on the prevention of parasitosis by Anisakis in fishery products supplied by establishments that serve food to final consumers or to communities came into force in Spain. In this study, a prevalence study of Anisakis in Madrid has been conducted to verify the prophylactic effects of the application of the law. Sera from 500 blood donors from the Fundación Jiménez Díaz University Hospital (Madrid/2021–2023) were collected, and the levels of anti-Anisakis IgG, IgA, and IgE were analyzed by ELISA, comparing them with those obtained with 110 donors from the Red Cross and the "Gómez Ulla" Central Defense Hospital (Madrid/2001–2002). The percentages of positivity in the 2021–2023 donor group were IgG (13.6%), IgA (13.6%), and IgE (2.2%), while in the 2001–2002 donors they were positive for IgG (15.45%), IgA (14.54%), and IgE (11.65%). A reduction of more than 80% was observed in the prevalence of anti-Anisakis IgE in the healthy population of Madrid, which confirmed the positive effect of RD1420/2006, which was later incorporated into RD1021/2022. [ABSTRACT FROM AUTHOR]

Lyme borreliosis (LB), a tick-borne infection caused by bacteria in the Borrelia burgdorferi sensu lato complex, is increasingly prevalent on the Balkan Peninsula, including Bulgaria, where it is the most common tick-borne disease. This study aimed to assess the seroprevalence of LB across Bulgaria by analyzing 1892 serum samples for specific IgG antibodies using a two-tier testing protocol involving an ELISA and immunoblot methods. The results revealed an overall seroprevalence rate of 5.4%, with significant variation based on age, sex, and residence. Seroprevalence increased with age, peaking at 8.4% in individuals over 65 years. Males had a seroprevalence of 8.4% compared to 3.3% in females, and rural residents showed higher seroprevalence (10.2%) compared to urban residents (4.4%). Regional analysis indicated that seroprevalence ranged from 0.0% to 20.0%, with higher rates in northern provinces such as Gabrovo (18.9%) and Targovishte (20.0%). This study highlights the importance of two-step testing protocols for accurate diagnosis and underscores the need for increased awareness and further research to enhance public health measures and the management of LB in Bulgaria. [ABSTRACT FROM AUTHOR]

Toxoplasmosis ranks among the most prevalent parasitic diseases globally. It seems that chronic toxoplasmosis is associated with several neuropsychiatric and other harmful effects in infected people, therefore, there is a need to investigate the prevalence of toxoplasmosis across various world regions. In this study, we conducted a meticulous meta-analysis to estimate the seroprevalence of anti-Toxoplasma gondii IgG antibodies within the general population in Iran (GPI). International and national scientific databases for studies published between January 1, 2000, and September 30, 2023, were searched. Observational studies reporting anti-T. gondii IgG seroprevalence in the GPI was selected/included. The data were synthesized using a random-effects model to calculate with a 95% confidence interval (95% CI) the national and regional anti-T. gondii IgG seroprevalence rates in Iran. Additionally, subgroup analyses were conducted to investigate the frequency of exposition to T. gondii in different socio-demographic, climatic, and geographical scenarios. From 18661 identified studies, 327 were included in the present meta-analysis, encompassing 122,882 individuals across the 31 Iranian provinces. The pooled nationwide anti-T. gondii IgG seroprevalence among the GPI was determined to be 32.9% (95% CI: 30.9–35.1%). The highest anti-T. gondii IgG seroprevalence was observed in Mazandaran province (North of Iran) (61%), whereas the lowest was in Semnan province (12.5%).Anti-T. gondii IgG seroprevalence demonstrated a higher occurrence in provinces characterized by moderate temperatures of 16–21°C, high relative humidity, and annual precipitation. Additionally, a higher anti-T. gondii IgG seroprevalence was identified among individuals with a habit of consumption of undercooked meat, raw fruits or vegetables, and untreated water. Moreover, those reporting direct contact with cats, possessing a lower level of education, residing in rural areas, being engaged in farming occupations, or playing the role of housewives exhibited higher anti-T. gondii IgG seroprevalence figures.The anti-T. gondii IgG seroprevalence within GPI closely aligns with the estimated worldwide average exposition rates. This underscores the imperative for public health policymakers to prioritize educational efforts regarding toxoplasmosis transmission pathways and its link to harmful effects. [ABSTRACT FROM AUTHOR]

Background: Sequential population-based household serosurveys of SARS-CoV-2 covering the COVID-19 pre- and post-vaccination periods are scarce in Brazil. This study investigated seropositivity trends in the municipality of São Paulo. Methods: We conducted seven cross-sectional surveys of adult population-representative samples between June 2020 and April 2022. The study design included probabilistic sampling, test for SARS-CoV-2 antibodies using the Roche Elecsys anti-nucleocapsid assay, and statistical adjustments for population demographics and non-response. The weighted seroprevalences with 95% confidence intervals (CI) were estimated by sex, age group, race, schooling, and mean income study strata. Time trends in seropositivity were assessed using the Joinpoint model. We compared infection-induced seroprevalences with COVID-19 reported cases in the pre-vaccination period. Results: The study sample comprised 8,134 adults. The overall SARS-CoV-2 seroprevalence increased from 11.4% (95%CI: 9.2–13.6) in June 2020 to 24.9% (95%CI: 21.0–28.7) in January 2021; from 38.1% (95%CI: 34.3–41.9) in April 2021 to 77.7% (95%CI: 74.4–81.0) in April 2022. The prevalence over time was higher in the subgroup 18–39 years old than in the older groups from Survey 3 onwards. The self-declared Black or mixed (Pardo) group showed a higher prevalence in all surveys compared to the White group. Monthly prevalence rose steeply from January 2021 onwards, particularly among those aged 60 years or older. The infection-to-case ratios ranged from 8.9 in June 2020 to 4.3 in January 2021. Conclusions: The overall seroprevalence rose significantly over time and with age and race subgroup variations. Increases in the 60 years or older age and the White groups were faster than in younger ages and Black or mixed (Pardo) race groups in the post-vaccination period. Our data may add to the understanding of the complex and changing population dynamics of the SARS-CoV-2 infection, including the impact of vaccination strategies and the modelling of future epidemiological scenarios. [ABSTRACT FROM AUTHOR]

Background: Natural infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or vaccination triggers antibody production against key viral antigens. However, there is limited evidence on the levels of antibodies produced in naturally infected individuals compared to those vaccinated in Ethiopia. Therefore, we aimed to detect and compare SARS-CoV-2 antibodies produced by naturally infected and vaccinated individuals. Materials and methods: We conducted a multicenter cross-sectional study among a total of 355 naturally infected and 355 vaccinated individuals from November 2022 to April 2023 at 10 selected health facilities in Addis Ababa, Ethiopia. We enrolled the participants consecutively upon their arrival at health facilities until the required sample size was achieved. We used a structured questionnaire to collect data on the demographic and clinical characteristics of the participants. We also collected 3–5 ml of blood samples from all participants and tested for anti-Spike (anti-S) and anti-nucleocapsid (anti-N) antibodies using Cobas 6000. We utilized frequency, mean, or median to describe the data, the Mann-Whitney U test to compare groups, and a generalized linear regression model to assess factors associated with anti-S antibody concentration. We analyzed the data with SPSS version 26, and the level of significance was set at P-value < 0.05. Results: Of the naturally infected participants, 352 (99.5%) had anti-S antibodies and all (100%) had anti-N antibodies, whereas among vaccinated participants, all (100%) had anti-S antibodies, while 323 (91.6%) had anti-N antibodies. Anti-S antibodies produced by vaccinated individuals were significantly (P < 0.001) higher than those produced as a result of natural infection. Being young (P = 0.004), having hypertension (P < 0.001), and having diabetes (P < 0.001) were significantly associated with lower anti-S antibody levels, while being recently vaccinated and having a higher number of vaccine doses were significantly associated with higher anti-S antibody concentrations in vaccinated participants. Having diabetes (P < 0.001) were significantly associated with lower anti-S concentrations in participants who were naturally infected. Conclusion: There is a high seropositivity rate in both naturally infected and vaccinated individuals. However, vaccinated individuals had higher levels of SARS-CoV-2 antibodies than those who were naturally infected, which highlights the significant contribution of vaccination in increasing the protection of COVID-19 in Ethiopia. [ABSTRACT FROM AUTHOR]

Background: According to Norwegian registries, 91% of individuals ≥ 16 years had received ≥ 1 dose of COVID-19 vaccine by mid-July 2022, whereas less than 2% of children < 12 years were vaccinated. Confirmed COVID-19 was reported for 27% of the population, but relaxation of testing lead to substantial underreporting. We have characterized the humoral immunity to SARS-CoV-2 in Norway in the late summer of 2022 by estimating the seroprevalence and identifying antibody profiles based on reactivity to Wuhan or Omicron-like viruses in a nationwide cross-sectional collection of residual sera, and validated our findings using cohort sera. Methods: 1,914 anonymized convenience sera and 243 NorFlu-cohort sera previously collected from the Oslo-area with reported infection and vaccination status were analyzed for antibodies against spike, the receptor-binding domain (RBD) of the ancestral Wuhan strain and Omicron BA.2 RBD, and nucleocapsid (N). Samples were also tested for antibodies inhibiting RBD-ACE2 interaction. Neutralization assays were performed on subsets of residual sera against B.1, BA.2, XBB.1.5 and BQ.1.1. Results: The national seroprevalence estimate from vaccination and/or infection was 99.1% (95% CrI 97.0-100.0%) based on Wuhan (spike_W and RBD_W) and RBD_BA2 antibodies. Sera from children < 12 years had 2.2 times higher levels of antibodies against RBD_BA2 than RBD_W and their seroprevalence estimate showed a 14.4 percentage points increase when also including anti-RBD_BA2 antibodies compared to Wuhan-antibodies alone. 50.3% (95% CI 45.0-55.5%) of residual sera from children and 38.1% (95% CI 36.0-40.4%) of all residual sera were positive for anti-N-antibodies. By combining measurements of binding- and ACE2-RBD-interaction-inhibiting antibodies, reactivity profiles indicative of infection and vaccination history were identified and validated using cohort sera. Residual sera with a profile indicative of hybrid immunity were able to neutralize newer Omicron variants XBB.1.5 and BQ.1.1. Conclusions: By late summer of 2022, most of the Norwegian population had antibodies to SARS-CoV-2, and almost all children had been infected. Antibody profiles indicated that children mostly had experienced a primary Omicron infection, while hybrid immunity was common among adults. The finding that sera displaying hybrid immunity could neutralize newer Omicron variants indicates that Wuhan-like priming of the immune response did not have a harmful imprinting effect and that infections induce cross-reacting antibodies against future variants. [ABSTRACT FROM AUTHOR]

A cross-sectional study on severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) seroprevalence among unvaccinated people living with HIV (PLWH) was conducted in Kampala, Uganda, in 2022. Data collection was done using a structured questionnaire. SARS-CoV-2 serologies were done using the Roche Elecsys Anti-SARS-CoV-2 S immunoassay, which assesses the adaptive humoral immune response to the SARS-CoV-2 Spike protein. A total of 575 PLWH (female n=355, 61.7%) with a median age of 49 years (IQR 39-55) were included. SARS-CoV-2 seroprevalence was 93%. The majority had antibody concentration levels ὅ 250 U/ml (n=383, 66.6%). Participants aged >55 years were significantly more likely to have lower antibody concentrations compared to younger participants (p-value < 0.001). A high BMI (= 30 kg/m2) was significantly associated with higher antibody concentrations (p-value 0.001). Concerning COVID-19 history, a small proportion of participants (n=79, 13.6%) reported contact with a known COVID-19 patient. Only 8.1% (n=47) had ever had a nasopharyngeal swab for SARS-CoV-2 RT-PCR done, and 3.1% (n=18) actually had a laboratory-confirmed SARS-CoV-2 infection in the past. SARS-CoV-2 seroprevalence was high among our study population, which may be attributed to the fact that the study took place right after all restrictions were lifted and the population was exposed to the dominant Omicron variant. Interestingly, only a small proportion of infections had been laboratory-confirmed. [ABSTRACT FROM AUTHOR]

Background: Toxoplasma gondii (T. gondii) is a ubiquitous protozoan parasite on our planet that causes toxoplasmosis. This study evaluated the seroprevalence and related risk factors for T. gondii infection in a population referred to healthcare centers in Meshkin-Shahr, Northwest Iran. Methods: A total of 400 blood samples were randomly collected from the general population and assessed using the anti-Toxoplasma antibodies, Immunoglobulin G and M (IgG and IgM) Enzyme-linked immunosorbent assay (ELISA) Kits in two steps before and during the coronavirus disease 2019 (COVID-19) pandemic, 2019–2020. The results were analyzed through logistic regression via SPSS 26 software. Results: Before the COVID-19 pandemic, anti-toxoplasma antibodies were detected in 39% of individuals (IgG: 38%, IgM: 0.5%, and IgG-IgM: 0.5%). Among the eleven risk factors evaluated, contact with soil and people awareness were significantly associated with T. gondii infection (p < 0.05). However, factors such as females, 20–39 age groups, junior high schools, housewives, rural areas, raw meat or vegetable consumption, vegetable or fruits washed by water, not detergent, and cat owners did not show a significant relationship with seropositivity (p > 0.05). After the outbreak of the COVID-19 pandemic, the overall seroprevalence for anti-T. gondii antibody increased to 49.7% (IgG: 47.7%, IgM: 0.5%, and IgG and IgM: 1.5%). Among these patients, 26% were positive for COVID-19. Additionally, before the COVID-19 pandemic, 40 samples were negative for anti-T. gondii antibodies but later became positive. The crude and adjusted models suggested that toxoplasmosis may be a possible risk factor for increased susceptibility to COVID-19, with an odds ratio (OR) of 1.28 (95% confidence interval (CI), 0.82–1.99; P < 0.05). Conversely, a non-significant protective effect against latent toxoplasmosis was observed in COVID-19-positive individuals (OR = 0.99; 95% CI, 0.51–1.92; P > 0.05), and COVID-19 positivity did not increase the levels of anti-T. gondii IgG antibodies. Conclusions: The general population in this region had a moderate seroprevalence of T. gondii. The increased number of COVID-19-positive patients with latent toxoplasmosis highlights the need to pay attention to the early diagnosis and proper treatment of toxoplasmosis in these patients and implement preventive programs in these areas for future possible viral infections. [ABSTRACT FROM AUTHOR]

We obtained samples from the Department of Defense Serum Repository from soldiers who were stationed at Fort Liberty, North Carolina, between 1991 and 2019 to assess temporal trends in tick-borne rickettsiosis and ehrlichiosis. Serological evidence of infection was common, with nearly 1 in 5 (18.9%) demonstrating antibodies. We observed significant decreases in Rickettsia seroprevalence (adjusted odds ratio [aOR], 0.42 [95% CI,.27–.65], P =.0001) while over the same period Ehrlichia seroprevalence, albeit less common, nearly doubled (aOR, 3.61 [95% CI, 1.10–13.99], P =.048). The increase in Ehrlichia seroprevalence likely reflects increased transmission resulting from the expanding geographic range of the lone star tick. [ABSTRACT FROM AUTHOR]

Background: Diphtheria is a re-emerging infectious disease and public health concern worldwide and in Vietnam with increasing cases in recent years. This study aimed to assess the anti-diphtheria toxoid antibodies status in Khanh Hoa Province and identify factors contributing to the vaccination policy in the south-central coast of Vietnam. Methods: This was a cross-sectional study to evaluate the seroprevalence of anti-diphtheria toxoid antibodies among 1,195 participants, aged 5 – 40 years in Khanh Hoa Province, Vietnam. Immunoglobulin G antibody levels against diphtheria were detected using a commercial anti-diphtheria toxoid enzyme-linked immunosorbent assay (SERION ELISA classic Diphtheria Immunoglobulin G) and were categorized following the World Health Organization guidelines. Results: The mean anti-diphtheria toxoid antibody levels were 0.07 IU/ml (95% Confidence Interval: 0.07–0.08). Anti-diphtheria toxoid antibody levels were found to be associated with age and history of diphtheria vaccination. The 5–15 years age group had the highest levels (0.09 IU/ml), while the older age group had the lowest antibody level (p < 0.001). Individuals who received three doses (adjusted Odds ratio: 2.34, 95%CI: 1.35 – 4.07) or 4+ doses (adjusted Odds ratio: 2.45, 95%CI: 1.29 – 4.64) had a higher antibody level compared to those who received only one dose regardless of age. Conclusion: It is crucial to promote routine vaccination coverage to over 95% for children under one year of age with three primary doses of the diphtheria-containing vaccine, including additional doses at 18 months and 7 years of age. Booster doses should be promoted and administered to adolescents and adults every 10 years. [ABSTRACT FROM AUTHOR]

Japanese encephalitis virus (JEV) is a major threat to human health. Bangladesh is considering introducing a JEV vaccine; however, the investment case is hampered by a limited understanding of key aspects of JEV ecology. We conducted a seroprevalence study in a high-incidence region using an assay that limits cross-reactivity with dengue virus. We also trapped mosquitoes and collected information about potential host species. We used mathematical models to recover risk factors for infection and underlying probabilities of severe disease and death. We observed 19.0% [95% confidence interval (CI):17.1 to 21.1] of JEV antibodies. On average, 0.7% (95% CI: 0.2 to 2.0) of the susceptible population gets infected yearly, with pig proximity being the main human infection risk factor. Our traps captured 10 different mosquito species that have been linked with JEV transmission. We estimated that 1 in 1000 infections results in severe disease, 1 in 10,000 results in death, and 76% of severe cases are missed by surveillance. [ABSTRACT FROM AUTHOR]

Background: The rising prevalence of herpes simplex type 2 (HSV-2) infection poses a growing global public health challenge. A comprehensive understanding of its epidemiology and burden disparities in China is crucial for informing targeted and effective intervention strategies in the future. Methods: We followed Cochrane and PRISMA guidelines for a systematic review and included publications published in Chinese and English bibliographic systems until March 31st, 2024. We synthesized HSV-2 seroprevalence data across different population types. We used random-effects models for metaanalyses and conducted meta-regression to assess the association between population characteristics and seroprevalence. Results: Overall, 23,999 articles were identified, and 402 publications (1,203,362 participants) that reported the overall seroprevalence rates (858 stratified measures) were included. Pooled HSV-2 seroprevalence among the general population (lower risk) was 7.7% (95% CI: 6.8-8.7%). Compared to the general population, there is a higher risk of HSV-2 prevalence among intermediate-risk populations (14.8%, 95% CI: 11.0-19.1%), and key populations (31.7%, 95% CI: 27.4-36.1%). Female sexual workers (FSWs) have the highest HSV-2 risk (ARR:1.69, 95% CI: 1.61-1.78). We found northeastern regions had a higher HSV-2 seroprevalence than other regions (17.0%, 95% CI: 4.3-35.6%, ARR: 1.38, 95% CI: 1.26-1.50, Northern China as the reference group). This highlighted the disparity by population risk levels and regions. We also found lower HSV-2 prevalence estimates in publications in Chinese bibliographic databases than those in English databases among key populations (such as MSM and HIVdiscordant populations). Conclusion: There is a gradient increase in HSV-2 prevalence risk stratification. We also identified region, population, and age disparities and heterogeneities by publication language in the HSV-2 burden. This study provides guidance for future HSV-2 prevention to eliminate disparities of HSV-2 infection and reduce overall HSV-2 burden. [ABSTRACT FROM AUTHOR]