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Background: Most of the rickettsioses are transmitted by ticks, and often overlooked by the medical profession, but are clinically important as they cause major human diseases. Recent studies have shown the existence of some rickettsial species in Iran, but very little information is available about the status of rickettsial epidemiology and ecology. This study investigated the presence of Rickettsia spp. in ticks and ruminants in western of Iran by molecular methods. Materials and Methods: 250 blood samples were collected from sheep and goats, as well as 244 ticks were collected opportunistically from ruminants in the Kurdistan province. The collected samples were tested using a real-time quantitative PCR (qPCR) assay targeting the Rickettsia16SrRNA gene. Rickettsia spp. positive by the qPCR were further amplified by conventional PCR of the gltA and OmpA genes. These ampliqons were further analyzed by sequencing. Results: The ticks species collected in this study included Rhipicephalus sanguineus, Rh. turanicus, Haemaphysalis concinna, and Dermacentor marginatus. In total, DNA of Rickettsia spp. was detected in 131 collected ticks (53.7%). Of the positives, Rickettsia slovaca (59.2%) and Ri. hoogstraalii (16.3%) were the most common species identified followed by Ri. raoultii, Ri. massiliae, Ri. sibirica, and Ri. conorii subsp. israelensis. In contrast, there were no positives observed in the blood samples collected from ruminants. Conclusion: The results indicate the presence of rickettsial species in ticks. The detection of these pathogens is significant because they cause clinical disease in humans. The results support the notion that the Iranian public health system needs to be more aware of these diseases. [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]

Summary: Background: Ticks can harm horses and transmit diseases, making them a growing concern for owners and veterinarians. Veterinarians play a crucial role in providing advice on tick prevention and control. Yet, no research has examined their perspectives on equine ticks and tick‐borne disease (TBD). Objectives: The objective was to assess equine veterinarians' experiences, knowledge and practices related to fundamental aspects of tick biology and identification, tick bite prevention and TBD in the United States. Study design: This project surveyed equine veterinarians in the United States about their knowledge of ticks and TBD affecting horses using nonprobability convenience sampling. The survey questions were grouped into six categories: respondent demographics, knowledge of ticks and TBDs, tick control option availability, tick and TBD frequency in horses and veterinary education and information availability. Methods: Data were analysed using descriptive statistics, chi‐square analysis and t‐tests. The sample was divided into Northeast and United States veterinarians, and a significance level of p < 0.05 was set. The study aimed to inform continuing education development for veterinarians by assessing their knowledge, practices and perceptions of ticks and TBDs. Results: The results indicate that while equine veterinarians know the importance of TBDs in equine health, knowledge on ticks and TBDs varies significantly. Main limitations: Limitations for the current study include potential response bias and a limited sample from many states. Conclusions: There is a need for increased tick control and prevention options and more animal‐specific resources for tick and TBD prevention. Veterinarians and horse owners require greater education and comprehensive information to prevent tick‐borne illnesses in horses. Collaborations between academia, industry and the human medicine community are suggested to build capacity for training veterinarians. [ABSTRACT FROM AUTHOR]

Ticks are a common source for a variety of microorganisms especially those which are pathogenic or highly fatal. Hyalomma species are potential vectors for the CCHF virus. This study sought to identify Hyalomma spp. isolated form sheep and camel found in the Al- Samawah desert of Al-Muthanna Province. Sixty samples of ticks were used in this study, and each was subjected to PCR and partial gene sequencing using the 18S rRNA gene. The results from the analysis showed that 45 of 60 samples (75%) were identified as Hyalomma spp. While 17 PCR-purified products were chosen for sequencing, and the aligned data were used to build the phylogenetic tree. Uphill climbing the roof of phylogenetic analysis, the result reigned these isolates in this study as Hyalomma asiaticum related to several isolates in GenBank. This research has shown that these ticks of sheep and camel in the Al-Samawah desert of Al-Muthanna Province are commonly a marker of many viruses, including the CCHF virus. Further in-depth work ought to be completed as a priority for disease control purposes. [ABSTRACT FROM AUTHOR]

Background: Lyme borreliosis (LB), caused by Borrelia burgdorferi sensu lato (Bbsl), is the most common tick-borne disease in Europe. Although public health surveillance for LB has been conducted in Romania since 2007, the extent of under-detection of Bbsl infections by LB surveillance has not been estimated. We therefore estimated the under-detection of symptomatic Bbsl infections by LB surveillance to better understand the LB burden in Romania. Methods: The number of incident symptomatic Bbsl infections were estimated from a seroprevalence study conducted in six counties (population 2.3 M) and estimates of the symptomatic proportion and duration of persistence of anti-Bbsl immunoglobulin G (IgG) antibodies. The number of incident symptomatic Bbsl infections were compared with the number of surveillance-reported LB cases to derive an under-detection multiplier, and then the under-detection multiplier was applied to LB surveillance data to estimate the incidence of symptomatic Bbsl infection from 2018 to 2023. Results: We estimate that there were 1968 individuals with incident symptomatic Bbsl infection in the six counties where the seroprevalence study was conducted in 2020, compared with the 187 surveillance-reported LB cases, resulting in an under-detection multiplier of 10.5 (i.e., for every surveillance-reported LB case, there were 10.5 symptomatic incident Bbsl infections). The incidence of symptomatic Bbsl infection in the six counties was 86.9/100,000 population in 2023, similar to the incidence in 2018−2020 (86.0) and higher than in 2021−2022 (40.3). Conclusions: There is a higher incidence of symptomatic Bbsl infection than is reported through public health surveillance for LB in Romania. Additional efforts are needed to strengthen disease prevention and address the important public health problem of LB. [ABSTRACT FROM AUTHOR]

Aims: Although tick‐borne disease (TBD) incidence has increased in the United States (U.S.) in the past decade, new evidence suggests that notifiable diseases surveillance records may not accurately reflect the true magnitude of TBD diagnoses. Furthermore, while regional electronic health records (EHR) are readily accessible their potential use as a more stable and consistent source of TBD diagnoses data has remained largely unexplored. Methods and Results: In this study, we used EHR from a database of more than 100 hospitals, healthcare networks, and insurance providers in Indiana, U.S., to better understand incidence, spatio‐temporal and demographic distribution of TBD Diagnoses from 2009–2018. Our results revealed that in Indiana, from 2009 to 2018, there were 5173 unique TBD Diagnoses across three diagnoses categories: Lyme disease (72.5%, n = 3751), Rickettsioses (12.0%, n = 623) and Other TBD Diagnoses (15.4%, n = 799). Using EHR, the average yearly Lyme disease diagnoses was more than double the cases obtained using notifiable disease surveillance data for the same period. Patients with a TBD Diagnoses were generally older (ages 45–59) and less racially diverse (96.3% white). Rickettsiosis diagnoses were reported more among male patients (55.2%), while Lyme disease diagnoses were higher among female patients (57.1%). Temporal data illustrated higher frequencies of diagnoses from May to July. Hot spot analysis identified a Lyme disease hot spot in northwest Indiana, while hotspots of Rickettsiosis and Other TBD Diagnoses category were identified in southwest Indiana. Extrapolated to the Indiana population, chi‐squared (χ2) tests of independence revealed that the observed distribution of TBD diagnoses in our data was significantly different from the expected distribution in the Indiana population‐based race, gender and age groups. Conclusions: Our study findings demonstrate that in Indiana, EHR provide a stable data source for elucidating TBD disease burden and for monitoring spatio‐temporal trends in TBD diagnoses. [ABSTRACT FROM AUTHOR]

Opportunistic sampling of ticks from animals during veterinary treatment offers important insights about wildlife exposure to pathogens. Here, we report pathogens and other tick‐borne organisms detected in ticks sampled from 10 animal species in and near Laikipia County, Kenya, in 2014–2016. Pathogen analysis was performed using a combination of Fluidigm PCR and Illumina sequencing. We detected a suite of important pathogens affecting human and domestic and wild animal health, including Anaplasma marginale, Rickettsia africae and Theileria parva. These findings expand our limited understanding of wildlife exposure to tick‐borne pathogens and potential ramifications for animal health and conservation. [ABSTRACT FROM AUTHOR]

Crimean-Congo hemorrhagic fever (CCHF) is a widespread tick-borne viral disease. YKL-40 (also known as chitinase-3-like-1 protein) is an acute phase protein released by various immune cells. The purpose of this study was to investigate the relationship between YKL-40 level and the clinical course and prognosis of CCHF. The study included 78 patients who were admitted to our hospital between April 15 and 30 August 2022 and had a positive polymerase chain reaction test result for CCHF. The patients were divided into two groups, severe and non-severe. In addition, a control group consisting of 22 healthy people was established. Mean serum YKL-40 levels were significantly higher in patients than controls (106.8 ng/mL ± 91.2 and 47.1 ng/mL ± 35.3, respectively; p < 0.001). However, mean YKL-40 levels were also significantly higher in patients with severe CCHF compared to non-severe cases (173.3 ± 112.3 and 67.5 ± 41.7, respectively; p < 0.001). A comparison of the 10 exitus patients and the 68 survivors revealed significantly higher YKL-40 levels in the exitus group (mean: 214.0 ± 139.0 and 92.8 ± 73.6, respectively; p = 0.001). A receiver operating characteristic analysis for YKL-40 levels to distinguish between severe and non-severe patients found an area under the curve of 0.925. YKL-40 levels were measured with a sensitivity of 97% and a specificity of 84% with a cutoff value of 90.7 ng/mL. YKL-40 levels measured at the time of hospital presentation in patients with CCHF can be used as a biomarker for clinical course and prognosis. [ABSTRACT FROM AUTHOR]

Rocky Mountain spotted fever (RMSF) is a severe tickborne disease that can reach epidemic proportions in communities with certain social and ecologic risk factors. In some areas, the case-fatality rate of brown dog tick-associated RMSF is up to 50%. Because of the spread of brown dog tick–associated RMSF in the southwestern United States and northern Mexico, the disease has the potential to emerge and become endemic in other communities that have large populations of free-roaming dogs, brown dog ticks, limited resources, and low provider awareness of the disease. By using a One Health approach, interdisciplinary teams can identify communities at risk and prevent severe or fatal RMSF in humans before cases occur. We have developed a conceptual framework for RMSF prevention to enable communities to identify their RMSF risk level and implement prevention and control strategies.

We evaluated spatial-temporal risk for Lyme disease in northwestern North Carolina, USA, by using individual-level canine Borrelia burgdorferi seroprevalence data collected during 2017–2021 at routine veterinary screenings for tickborne diseases. Seroprevalence in dogs increased from 2.2% (47/2,130) in 2017 to 11.2% (339/3,033) in 2021. The percentage of incident seropositivity increased from 2.1% (45/2,130) in 2017 to 7.6% (231/3,033) in 2021. Exploratory geographic analyses found canine seroprevalence shifted from clustered (2017, Moran’s I = 0.30) to dispersed (2021, Moran’s I = −0.20). Elevation, slope, aspect, and forest land cover density were associated with canine seroprevalence within various household buffer regions in 2017. Slope was associated with seroprevalence at the household level in 2021. Results support the use of individual-level canine seroprevalence data for monitoring human risk for Lyme disease. Establishing sentinel veterinary clinics within Lyme disease–emergent communities might promote prevention and control efforts and provide opportunities for educational and behavioral interventions.

Abstract Background Lyme borreliosis (LB), caused by Borrelia burgdorferi sensu lato (Bbsl), is the most common tick-borne disease in Europe. Although public health surveillance for LB has been conducted in Romania since 2007, the extent of under-detection of Bbsl infections by LB surveillance has not been estimated. We therefore estimated the under-detection of symptomatic Bbsl infections by LB surveillance to better understand the LB burden in Romania. Methods The number of incident symptomatic Bbsl infections were estimated from a seroprevalence study conducted in six counties (population 2.3 M) and estimates of the symptomatic proportion and duration of persistence of anti-Bbsl immunoglobulin G (IgG) antibodies. The number of incident symptomatic Bbsl infections were compared with the number of surveillance-reported LB cases to derive an under-detection multiplier, and then the under-detection multiplier was applied to LB surveillance data to estimate the incidence of symptomatic Bbsl infection from 2018 to 2023. Results We estimate that there were 1968 individuals with incident symptomatic Bbsl infection in the six counties where the seroprevalence study was conducted in 2020, compared with the 187 surveillance-reported LB cases, resulting in an under-detection multiplier of 10.5 (i.e., for every surveillance-reported LB case, there were 10.5 symptomatic incident Bbsl infections). The incidence of symptomatic Bbsl infection in the six counties was 86.9/100,000 population in 2023, similar to the incidence in 2018−2020 (86.0) and higher than in 2021−2022 (40.3). Conclusions There is a higher incidence of symptomatic Bbsl infection than is reported through public health surveillance for LB in Romania. Additional efforts are needed to strengthen disease prevention and address the important public health problem of LB. Graphic Abstract

Human granulocytic anaplasmosis (HGA) is a tick-borne infection caused by Anaplasma phagocytophilum. Only seven cases of HGA have been reported in Japan to date. We report the case of a 61-year-old female farmer who developed HGA with rash and rhabdomyolysis. The patient had fever and erythema covering the entire body, including the palms. An induration with an eschar was observed on the right leg, indicating that the patient had been bitten by a tick. Elevated serum creatinine and creatinine kinase levels and hematuria indicated rhabdomyolysis. We suspected Japanese spotted fever, a tick-borne illness caused by Rickettsia Japonica , and administered minocycline and ciprofloxacin for a week. Transient neutropenia and thrombocytopenia were observed, but the symptoms improved. Polymerase chain reaction (PCR) and antibody tests for R. japonica and Orientia tsutsugamushi , which causes scrub typhus, were both negative. The PCR test for severe fever with thrombocytopenia syndrome virus was also negative. Antibodies against A. phagocytophilum –related proteins were detected by western blotting, indicating seroconversion of IgG with paired serum samples, and the patient was diagnosed with HGA. HGA should be suspected in acute febrile patients with a history of outdoor activity and cytopenia, with or without a rash. A testing system and the accumulation of cases in Japan are necessary for the early diagnosis and appropriate treatment of HGA. [ABSTRACT FROM AUTHOR]

Abstract An 11‐year‐old female spayed German Wirehaired Pointer with a 1‐week history of lethargy, hyporexia, diarrhea, and coughing presented with pericardial effusion causing cardiac tamponade. An echocardiogram revealed no structural cause for pericardial effusion. The pericardial effusion was an exudate with mixed macrophagic and neutrophilic inflammation. Morulae occasionally were found within neutrophils. The pericardial fluid and blood were qPCR and cPCR positive for Anaplasma phagocytophilum (NC State University, Vector‐borne Disease Diagnostic Laboratory, Raleigh, NC). The dog's blood was negative by ELISA (Vetscan Flex4 Rapid Test, Zoetis, Parsippany, NJ) for A. phagocytophilum antibodies at initial presentation and subsequently positive (SNAP4DxPlus, IDEXX, Westbrook, ME) 7 days later. After pericardiocentesis and administration of doxycycline (5 mg/kg PO q12h for 14 days), a repeat echocardiogram performed 1 month later showed no recurrence of pericardial effusion.

Abstract Background Ticks are obligate hematophagous ectoparasites involved in transmitting viruses of public health importance. The objective of this work was to identify the Jingmen tick virus in hard ticks from the Colombian Caribbean, an arbovirus of importance for public health. Methods Ticks were collected in rural areas of Córdoba and Cesar, Colombia. Taxonomic identification of ticks was carried out, and pools of 13 individuals were formed. RNA extraction was performed. Library preparation was performed with the MGIEasy kit, and next-generation sequencing (NGS) with MGI equipment. Bioinformatic analyses and taxonomic assignments were performed using the Galaxy platform, and phylogenetic analyses were done using IQ-TREE2. Results A total of 766 ticks were collected, of which 87.33% (669/766) were Rhipicephalus microplus, 5.4% (42/766) Dermacentor nitens, 4.2% (32/766) Rhipicephalus linnaei, and 3.0% (23/766) Amblyomma dissimile. Complete and partial segments 1, 2, 3, and 4 of Jingmen tick virus (JMTV) were detected in the metatranscriptome of the species R. microplus, D. nitens, and A. dissimile. The JMTVs detected are phylogenetically related to JMTVs detected in Aedes albopictus in France, JMTVs detected in R. microplus in Trinidad and Tobago, JMTVs in R. microplus and A. variegatum in the French Antilles, and JMTVs detected in R. microplus in Colombia. Interestingly, our sequences clustered closely with JMTV detected in humans from Kosovo. Conclusions JMTV was detected in R. microplus, D. nitens, and A. dissimile. JMTV could pose a risk to humans. Therefore, it is vital to establish epidemiological surveillance measures to better understand the possible role of JMTV in tropical diseases. Graphical Abstract

Abstract Background Severe fever with thrombocytopenia syndrome (SFTS) is an emerging tick-borne zoonosis caused by the SFTS virus (SFTSV). Understanding the prevalence of SFTSV RNA in humans, vertebrate hosts and ticks is crucial for SFTS control. Methods A systematic review and meta-analysis were conducted to determine the prevalence of SFTSV RNA in humans, vertebrate hosts and questing ticks. Nine electronic databases were searched for relevant publications, and data on SFTSV RNA prevalence were extracted. Pooled prevalence was estimated using a random effects model. Subgroup analysis and multivariable meta-regression were performed to investigate sources of heterogeneity. Results The pooled prevalence of SFTSV RNA in humans was 5.59% (95% confidence interval [CI] 2.78–9.15%) in those in close contact (close contacts) with infected individuals (infected cases) and 0.05% (95% CI 0.00–0.65%) in healthy individuals in endemic areas. The SFTSV infection rates in artiodactyls (5.60%; 95% CI 2.95–8.96%) and carnivores (6.34%; 95% CI 3.27–10.23%) were higher than those in rodents (0.45%; 95% CI 0.00–1.50%). Other animals, such as rabbits, hedgehogs and birds, also played significant roles in SFTSV transmission. The genus Haemaphysalis was the primary transmission vector, with members of Ixodes, Dermacentor, and Amblyomma also identified as potential vectors. The highest pooled prevalence was observed in adult ticks (1.03%; 95% CI 0.35–1.96%), followed by nymphs (0.66%; 95% CI 0.11–1.50%) and larvae (0.01%; 95% CI 0.00–0.46%). The pooled prevalence in ticks collected from endemic areas (1.86%; 95% CI 0.86–3.14%) was higher than that in ticks collected in other regions (0.41%; 95% CI 0.12–0.81%). Conclusions Latent SFTSV infections are present in healthy individuals residing in endemic areas, and close contacts with SFTS cases are at a significantly higher risk of infection. The type of animal is linked to infection rates in vertebrate hosts, while infection rates in ticks are associated with the developmental stage. Further research is needed to investigate the impact of various environmental factors on SFTSV prevalence in vertebrate hosts and ticks. Graphical Abstract

Introduction: This work aim to evaluate the association of procalcitonin (PCT) levels with disease severity and prognosis in severe fever with thrombocytopenia syndrome (SFTS) patients. Methodology: The medical records of 158 confirmed SFTS patients at two hospitals were reviewed. The patients were divided into survival group and nonsurvival group according to outcomes. Additionally, to assess mortality rates at different PCT levels, patients were divided into two groups, PCT < 0.25 ng/mL and PCT ≥ 0.25 ng/mL. Results: Among the 158 confirmed SFTS patients, 26 died; the case fatality rate was 16.46%. PCT data were available for 132 of these patients; 66 were in the PCT < 0.25 ng/mL group, and 66 were in the PCT ≥ 0.25 ng/mL group. The SFTS patients had abnormal results on routine blood tests, indicating varying degrees of thrombocytopenia and leukopenia, and most patients presented with multiple organ dysfunction. The PCT level of the nonsurvival group was significantly higher than that of the survival group (p < 0.01). Additionally, the mortality of the PCT ≥ 0.25 ng/mL group was significantly higher than that of the PCT < 0.25 ng/mL group (p < 0.01); mortality increased sharply (≥ 25%) when the PCT level exceeded 0.1 ng/mL. Conclusions: PCT levels in SFTS patients are closely related to the severity and prognosis of their illness. The serum PCT level is a promising predictor of mortality and severity in SFTS patients when considered in combination with clinical data and other laboratory tests. [ABSTRACT FROM AUTHOR]

Tick‐borne encephalitis (TBE) virus is considered the medically most important arthropod‐borne virus in Europe. Although TBE is endemic throughout central Europe, ticks and rodents determine its maintenance in small, difficult‐to‐assess, natural foci. We investigated the interrelation between the population genetics of the main TBE virus (TBEV) vector tick (Ixodes ricinus), the most important reservoir host (Myodes glareolus, syn. Clethrionomys glareolus), and TBEV. Rodents and ticks were sampled on 15 sites within an exploratory study area, which has been screened regularly for TBEV occurrence in ticks for more than 10 years. On all 15 sites, ticks and bank voles were sampled, screened for TBEV presence via serology and RT‐PCR, and genetically examined. Moreover, TBEV isolates derived from these analyses were sequenced. In long‐term TBEV foci bank vole populations show extraordinary genetic constitutions, leading to a particular population structure, whereas ticks revealed a panmictic genetic structure overall sampling sites. Landscape genetics and habitat connectivity modeling (analysis of isolation by resistance) showed no landscape‐related barriers explaining the genetic structure of the bank vole populations. The results suggest that bank voles do not simply serve as TBEV reservoirs, but their genetic composition appears to have a significant influence on establishing and maintaining long‐term natural TBEV foci, whereas the genetic structure of TBEV's main vector I. ricinus does not play an important role in the sustainability of long‐term TBEV foci. A thorough investigation of how and to which extent TBEV and M. glareolus genetics are associated is needed to further unravel the underlying mechanisms. [ABSTRACT FROM AUTHOR]

Simple Summary: We conducted a tick surveillance study in northwestern Spain with the aim of identifying tick-associated Rickettsia species among ticks removed from humans and to track how tick populations and their associated pathogens have changed over the years. Five genera and eight species of ticks were collected, with Ixodes ricinus being the most frequently found. By comparing our data with previous reports, a clear geographic and seasonal expansion of tick populations and the associated Rickettsia species is observed, indicating that the spatiotemporal patterns of ticks and bacteria have changed over the years. Considering the medical relevance of tick-borne rickettsioses, evaluating the infection risk to humans in tick-infested areas, as well as detecting spreading species, is essential for establishing adequate prevention and control measures. Tick-borne rickettsioses (TBRs) are distributed worldwide and are recognized as important emerging vector-borne zoonotic diseases in Europe. The aim of this study was to identify tick-associated Rickettsia among ticks removed from humans, and to track how tick populations and their associated pathogens have changed over the years. For this purpose, we conducted a tick surveillance study in northwestern Spain between 2018 and 2022. Ticks were morphologically identified and analyzed for the presence of rickettsial pathogens through the amplification of the citrate synthase (gltA) and the outer membrane protein A (ompA) genes. PCR products were sequenced and subjected to phylogenetic analyses. We collected 7397 ticks, with Ixodes ricinus being the species most frequently isolated. Based on the PCR results, Rickettsia DNA was detected in 1177 (15.91%) ticks, and 10 members of Rickettsia were identified: R. aeschlimannii, R. conorii subsp. conorii, R. conorii subsp. raoultii, R. massiliae, R. monacensis, R. sibirica subsp. mongolitimonae, R. slovaca, R. helvetica, Candidatus R. barbariae, and Candidatus R. rioja. Some of these Rickettsia have gone previously undetected in the study region. There is clear geographic and seasonal expansion not only of tick populations, but also of the associated Rickettsia. The comparison of our data with those obtained years ago provides a clear idea of how the spatiotemporal distributions of ticks and their associated Rickettsiae have changed over the years. [ABSTRACT FROM AUTHOR]

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Tick-borne illnesses (TBIs), especially those caused by Borrelia, are increasingly prevalent worldwide. These diseases progress through stages of initial localization, early spread, and late dissemination. The final stage often leads to post-treatment Lyme disease syndrome (PTLDS) or chronic Lyme disease (CLD), characterized by persistent and non-specific multisystem symptoms affecting multiple systems, lasting over six months after antibiotic therapy. PTLDS significantly reduces functional ability, with 82–96% of patients experiencing pain, including arthritis, arthralgia, and myalgia. Inflammatory markers like CRP and TNF-alpha indicate ongoing inflammation, but the link between chronic pain and other biomarkers is underexplored. This study examined the relationship between pain and biomarkers in TBI patients from an Irish hospital and their response to antibiotic treatment. Pain ratings significantly decreased after antibiotic treatment, with median pain scores dropping from 7 to 5 (U = 27215.50, p < 0.001). This suggests a persistent infection responsive to antibiotics. Age and gender did not influence pain ratings before and after treatment. The study found correlations between pain ratings and biomarkers such as transferrin, CD4%, platelets, and neutrophils. However, variations in these biomarkers did not significantly predict pain changes when considering biomarkers outside the study. These findings imply that included biomarkers do not directly predict pain changes, possibly indicating allostatic load in symptom variability among long-term TBI patients. The study emphasizes the need for appropriate antibiotic treatment for TBIs, highlighting human rights issues related to withholding pain relief. [ABSTRACT FROM AUTHOR]

Human monocytic ehrlichiosis, an emerging tick-borne disease, is caused by Ehrlichia chaffeensis. Infections with the pathogen are also common in the canine host. Our previous studies demonstrated that functional disruption within the E. chaffeensis phage head-to-tail connector protein gene results in bacterial attenuation, creating a modified live attenuated vaccine (MLAV). The MLAV confers protective immunity against intravenous and tick transmission challenges one month following vaccination. In this study, we evaluated the duration of MLAV protection. Dogs vaccinated with the MLAV were challenged with wild-type E. chaffeensis via intravenous infection at 4-, 8-, and 12-months post-vaccination. Immunized dogs rapidly cleared the wild-type pathogen infection and tested positive for bacteremia less frequently than unvaccinated controls. While immune responses varied among dogs, vaccinees consistently mounted IgG and CD4+ T-cell responses specific to E. chaffeensis throughout the assessment period. Our findings demonstrate that MLAV-mediated immune protection persists for at least one year against wild-type bacterial infection, marking a major advancement in combating this serious tick-borne disease. The data presented here serve as the foundation for further studies, elucidating the molecular mechanisms underlying virulence and vaccine development and aiding in preventing the diseases caused by E. chaffeensis and other tick-borne rickettsial pathogens. [ABSTRACT FROM AUTHOR]

Habitat fragmentation and host community composition are implicated as key drivers of changing tick populations and tick‐borne pathogen dynamics, altering infection risk through coupled socioecological pathways that mediate interactions between tick vectors, vertebrate hosts, and humans. Patterns of host diversity may be particularly idiosyncratic across urbanized landscapes, due to trade‐offs between extreme fragmentation that reduces habitat suitability and access, and human activities that artificially increase resource availability for wildlife. We used camera and hair trap surveys and tick sampling to identify links between landscape composition and configuration, the mammalian host community, and the presence of three tick vector species at a human–wildlife interface in New York City, an emerging area within an endemic region for several tick‐borne diseases. We found that human infrastructures, such as the presence of fences in yards, could affect mammal host community composition by changing the "hardness" of edges between urban greenspaces and residential areas. We identified yard‐ and broader landscape‐level features associated with the presence of urban mammal species, and identified cascading effects of host community composition on tick distribution in yards, suggesting management implications for the mitigation of human exposure to tick‐borne pathogens. In particular, we identified a possible role of ubiquitous mesomammals, such as raccoons (Procyon lotor), in transporting Amblyomma americanum ticks between parks and neighboring residential yards, and confirmed the key role of white‐tailed deer (Odocoileus virginianus) for introducing Ixodes scapularis ticks into yards. Our results challenge assumptions that biodiversity loss in human‐modified areas always increases the risk for tick‐borne diseases. Instead, we found many residential sites had higher mammal species richness and higher detection of low reservoir competent ("dilution") hosts for Borrelia burgdorferi, such as opossums (Didelphis virginiana), than paired forested greenspaces. Our study highlights the importance of disentangling the mechanisms mediating tick‐borne disease hazard as a critical first step toward reducing urban tick‐borne disease risk. [ABSTRACT FROM AUTHOR]

Due to the extensive use of green urban areas as recreation places, city residents are exposed to tick-borne pathogens. The objectives of our study were (i) to determine the occurrence of ticks in urban green areas, focussing on areas used by humans such as parks, schools and kindergartens, and urban forests, and (ii) to assess the prevalence of Borrelia infections in ticks in Zielona Góra, a medium-sized city in western Poland. A total of 161 ticks representing the two species Ixodes ricinus (34 males, 51 females, 30 nymphs) and Dermacentor reticulatus (20 males, 26 females) were collected from 29 of 72 (40.3%) study sites. In total, 26.1% of the ticks (85.7% of I. ricinus and 14.3% of D. reticulatus) yielded DNA of Borrelia. The difference in the infection rate between I. ricinus and D. reticulatus was significant. Among infected ticks, the most frequent spirochete species were B. lusitaniae (50.0%) and B. afzelii (26.2%), followed by B. spielmanii (9.5%), B. valaisiana (7.1%), B. burgdorferi sensu stricto, (4.8%) and B. miyamotoi (2.4%). No co-infections were found. We did not observe a correlation in the occurrence of Borrelia spirochetes in ticks found in individual study sites that differed in terms of habitat type and height of vegetation. Our findings demonstrate that the Borrelia transmission cycles are active within urban habitats, pointing the need for monitoring of tick-borne pathogens in public green areas. They could serve as guidelines for authorities for the proper management of urban green spaces in a way that may limit tick populations and the potential health risks posed by tick-borne pathogens. [ABSTRACT FROM AUTHOR]

Caprine babesiosis is a tick borne haemoprotozoan infection less frequently reported from Kerala. In the present report, we document a confirmed case of Babesia motasi for the first time in the state. A Sirohi Kathiavari crossbred goat was presented to the University Veterinary Hospital (UVH), Kokkalai with symptoms of anorexia and pyrexia. On blood smear examination, large and small forms of Babesia organisms in Giemsa's stain could be detected. Complete blood count revealed hypochromic microcytic anaemia with thrombocytopenia. Molecular confirmation was done with polymerase chain reaction (PCR) targeting 18S rRNA gene. A 390 bp fragment was obtained and sequenced which was confirmed as Babesia motasi. Babesia ovis or Theileria spp., could not be detected by PCR. This study reports the molecular confirmation of two forms of B. motasi in a crossbred goat from Kerala. [ABSTRACT FROM AUTHOR]

Rickettsia africae is a tick‐borne bacteria known to cause African tick bite fever (ATBF). While the disease was first described more than 100 years ago, knowledge of transmission risk factors and disease burden remain poorly described. To better understand the burden of R. africae, this article reviewed and summarized the published literature related to ATBF epidemiology and clinical management. Using a systematic approach, consistent with the PRISMA guidelines, we identified more than 100 eligible articles, including 65 epidemiological studies and 41 case reports. Most reports described R. africae in ticks and livestock, while human studies were less common. Human disease case reports were exclusively among returning travellers from non‐endemic areas, which limits our disease knowledge among at‐risk populations: people living in endemic regions. Substantial efforts to elucidate the ATBF risk factors and clinical manifestations among local populations are needed to develop effective preventative strategies and facilitate appropriate and timely diagnosis. [ABSTRACT FROM AUTHOR]

An 11‐year‐old female spayed German Wirehaired Pointer with a 1‐week history of lethargy, hyporexia, diarrhea, and coughing presented with pericardial effusion causing cardiac tamponade. An echocardiogram revealed no structural cause for pericardial effusion. The pericardial effusion was an exudate with mixed macrophagic and neutrophilic inflammation. Morulae occasionally were found within neutrophils. The pericardial fluid and blood were qPCR and cPCR positive for Anaplasma phagocytophilum (NC State University, Vector‐borne Disease Diagnostic Laboratory, Raleigh, NC). The dog's blood was negative by ELISA (Vetscan Flex4 Rapid Test, Zoetis, Parsippany, NJ) for A. phagocytophilum antibodies at initial presentation and subsequently positive (SNAP4DxPlus, IDEXX, Westbrook, ME) 7 days later. After pericardiocentesis and administration of doxycycline (5 mg/kg PO q12h for 14 days), a repeat echocardiogram performed 1 month later showed no recurrence of pericardial effusion. [ABSTRACT FROM AUTHOR]

Tick-borne diseases (TBDs) are a growing threat in Japan. However, distribution of ticks and their possession of human pathogens remain poorly understood. In the present study, we collected 3477 ticks at 6 remote, woodland sites in Ibaraki prefecture between May 23 and November 4, 2021, and investigated the distribution and the possession of spotted fever group Rickettia (SFGR). The collected ticks included Haemaphysalis flava (78.3 %), Haemaphysalis longicornis (9.0 %), Haemaphysalis hystricis (4.6 %), Ixodes turdus (4.3 %), Amblyomma testudinarium (2.1 %), Haemaphysalis cornigera (0.9 %), Haemaphysalis formosensis (0.9 %), Haemaphysalis megaspinosa (0.2 %), Ixodes ovatus (0.1 %), Ixodes nipponensis (0.09 %), and Ixodes columnae (0.03 %). Of 2160 DNA samples extracted from the ticks, the gltA gene and the 17-kDa antigen gene of SFGR were detected in 67 samples. Among 1682 samples from adult and nymph ticks, the positive rate of SFGR was 2.7 %. Sequence analyses of the partial 17-kDa antigen gene demonstrated that the detected SFGR were classified into 8 groups (G1 to G8). The sequences of G2, G4, G5, G6, and G7 were either identical to or differed by one base pair from those of Rickettsia asiatica , Rickettsia tamurae , Rickettsia monacensis , Rickettsia canadensis , and Rickettsia felis , respectively. The present study revealed a diverse tick fauna in Ibaraki prefecture, including detection of species commonly found in southwestern Japan. Although the prevalence of SFGR in ticks was lower than in previous studies, several SFGR causing human infection may be present. [ABSTRACT FROM AUTHOR]

Borrelia burgdorferi, a Lyme disease spirochete, causes a range of acute and chronic maladies in humans. However, a primary vertebrate reservoir in the United States, the white-footed deermouse Peromyscus leucopus, is reported not to have reduced fitness following infection. Although laboratory strains of Mus musculus mice have successfully been leveraged to model acute human Lyme disease, the ability of these rodents to model B. burgdorferi-P. leucopus interactions remains understudied. Here, we compared infection of P. leucopus with B. burgdorferi B31 with infection of the traditional B. burgdorferi murine models--C57BL/6J and C3H/HeN Mus musculus, which develop signs of inflammation akin to human disease. We find that B. burgdorferi was able to reach much higher burdens (10- to 30-times higher) in multiple M. musculus skin sites and that the overall dynamics of infection differed between the two rodent species. We also found that P. leucopus remained transmissive to larval Ixodes scapularis for a far shorter period than either M. musculus strain. In line with these observations, we found that P. leucopus does launch a modest but sustained inflammatory response against B. burgdorferi in the skin, which we hypothesize leads to reduced bacterial viability and rodent-to-tick transmission in these hosts. Similarly, we also observe evidence of inflammation in infected P. leucopus hearts. These observations provide new insight into reservoir species and the B. burgdorferi enzootic cycle. [ABSTRACT FROM AUTHOR]

Background: Ticks are obligate hematophagous ectoparasites involved in transmitting viruses of public health importance. The objective of this work was to identify the Jingmen tick virus in hard ticks from the Colombian Caribbean, an arbovirus of importance for public health. Methods: Ticks were collected in rural areas of Córdoba and Cesar, Colombia. Taxonomic identification of ticks was carried out, and pools of 13 individuals were formed. RNA extraction was performed. Library preparation was performed with the MGIEasy kit, and next-generation sequencing (NGS) with MGI equipment. Bioinformatic analyses and taxonomic assignments were performed using the Galaxy platform, and phylogenetic analyses were done using IQ-TREE2. Results: A total of 766 ticks were collected, of which 87.33% (669/766) were Rhipicephalus microplus, 5.4% (42/766) Dermacentor nitens, 4.2% (32/766) Rhipicephalus linnaei, and 3.0% (23/766) Amblyomma dissimile. Complete and partial segments 1, 2, 3, and 4 of Jingmen tick virus (JMTV) were detected in the metatranscriptome of the species R. microplus, D. nitens, and A. dissimile. The JMTVs detected are phylogenetically related to JMTVs detected in Aedes albopictus in France, JMTVs detected in R. microplus in Trinidad and Tobago, JMTVs in R. microplus and A. variegatum in the French Antilles, and JMTVs detected in R. microplus in Colombia. Interestingly, our sequences clustered closely with JMTV detected in humans from Kosovo. Conclusions: JMTV was detected in R. microplus, D. nitens, and A. dissimile. JMTV could pose a risk to humans. Therefore, it is vital to establish epidemiological surveillance measures to better understand the possible role of JMTV in tropical diseases. [ABSTRACT FROM AUTHOR]

Background: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging tick-borne zoonosis caused by the SFTS virus (SFTSV). Understanding the prevalence of SFTSV RNA in humans, vertebrate hosts and ticks is crucial for SFTS control. Methods: A systematic review and meta-analysis were conducted to determine the prevalence of SFTSV RNA in humans, vertebrate hosts and questing ticks. Nine electronic databases were searched for relevant publications, and data on SFTSV RNA prevalence were extracted. Pooled prevalence was estimated using a random effects model. Subgroup analysis and multivariable meta-regression were performed to investigate sources of heterogeneity. Results: The pooled prevalence of SFTSV RNA in humans was 5.59% (95% confidence interval [CI] 2.78–9.15%) in those in close contact (close contacts) with infected individuals (infected cases) and 0.05% (95% CI 0.00–0.65%) in healthy individuals in endemic areas. The SFTSV infection rates in artiodactyls (5.60%; 95% CI 2.95–8.96%) and carnivores (6.34%; 95% CI 3.27–10.23%) were higher than those in rodents (0.45%; 95% CI 0.00–1.50%). Other animals, such as rabbits, hedgehogs and birds, also played significant roles in SFTSV transmission. The genus Haemaphysalis was the primary transmission vector, with members of Ixodes, Dermacentor, and Amblyomma also identified as potential vectors. The highest pooled prevalence was observed in adult ticks (1.03%; 95% CI 0.35–1.96%), followed by nymphs (0.66%; 95% CI 0.11–1.50%) and larvae (0.01%; 95% CI 0.00–0.46%). The pooled prevalence in ticks collected from endemic areas (1.86%; 95% CI 0.86–3.14%) was higher than that in ticks collected in other regions (0.41%; 95% CI 0.12–0.81%). Conclusions: Latent SFTSV infections are present in healthy individuals residing in endemic areas, and close contacts with SFTS cases are at a significantly higher risk of infection. The type of animal is linked to infection rates in vertebrate hosts, while infection rates in ticks are associated with the developmental stage. Further research is needed to investigate the impact of various environmental factors on SFTSV prevalence in vertebrate hosts and ticks. [ABSTRACT FROM AUTHOR]

(1) Background: Crimean–Congo hemorrhagic fever (CCHF) is an emerging tick-borne disease endemic in Africa, Asia, the Middle East, and the Balkan and Mediterranean regions of Europe. Although no human CCHF cases have been reported, based on vector presence, serological evidence among small vertebrates, and the general human population, Hungary lies within high evidence consensus for potential CCHF introduction and future human infection. Thus, the aim of our pilot serosurvey was to assess CCHF seropositivity among cattle and sheep as indicator animals for virus circulation in the country. (2) Methods: In total, 1905 serum samples taken from free-range cattle and sheep in 2017 were tested for the presence of anti-CCHF virus IgG antibodies using commercial ELISA and commercial and in-house immunofluorescent assays. (3) Results: We found a total of eleven reactive samples (0.58%) from five administrative districts of Hungary comprising 8 cattle and 3 sheep. The most affected regions were the south–central and northwestern parts of the country. (4) Conclusions: Based on these results, more extended surveillance is advised, especially in the affected areas, and there should be greater awareness among clinicians and other high-risk populations of the emerging threat of CCHF in Hungary and Central Europe. [ABSTRACT FROM AUTHOR]

Tick-borne febrile illnesses caused by pathogens like Anaplasma spp., Bartonella spp., Borrelia spp., Ehrlichia spp., Coxiella burnetii, Francisella tularensis, and Rickettsia spp., are significant health concerns in Africa. The epidemiological occurrence of these pathogens is closely linked to the habitats of their vectors, prevalent in rural and semi-urban areas where humans and livestock coexist. The overlapping clinical presentations, non-specific symptoms, and limited access to commercially available in vitro diagnostics in resource-limited settings exacerbate the complexity of accurate diagnoses. This review aimed to systematically extract and analyze existing literature on tick-borne febrile illnesses in Africa, highlighting the diagnostic challenges and presenting an up-to-date overview of the most relevant pathogens affecting human populations. A comprehensive literature search from January 1990 to June 2024 using databases like PubMed, Cochrane Library, Science Direct, EMBASE, and Google Scholar yielded 13,420 articles, of which 70 met the inclusion criteria. Anaplasma spp. were reported in Morocco, Egypt, and South Africa; Francisella spp. in Kenya and Ethiopia; Ehrlichia spp. in Cameroon; Bartonella spp. in Senegal, Namibia, South Africa, and Ethiopia; Borrelia spp. in Senegal, Gabon, Tanzania, and Ethiopia; Coxiella burnetii in 10 countries including Senegal, Mali, and South Africa; and Rickettsia spp. in 14 countries including Senegal, Algeria, and Uganda. Data were analyzed using a fixed-effect model in R version 4.0.1 and visualized on an African map using Tableau version 2022.2. This review highlights the urgent need for improved diagnostics to better manage and control tick-borne febrile illnesses in Africa.

AbstractCrimean-Congo Hemorrhagic Fever (CCHF) presents significant global health challenges, highlighted by its sporadic nature and high fatality rates. The manuscript emphasizes the disease’s tendency to be under-recognized and the diagnostic challenges it poses, often mimicking other illnesses and leading to frequent misdiagnosis. There is a noted absence of robust diagnostic tools, specific treatments, or vaccines, leaving only supportive care generally available. The necessity for increased international cooperation and a coordinated strategy to enhance disease surveillance, public health preparedness, and community education is stressed. [ABSTRACT FROM AUTHOR]

Abstract Background Infectious diseases are emerging across temperate regions of the world, and, for some, links have been made between landscapes and emergence dynamics. For tick-borne diseases, public parks may be important exposure sites for people living in urbanized areas of North America and Europe. In most cases, we know more about the ecological processes that determine the hazard posed by ticks as disease vectors than we do about how human population exposure varies in urban natural parks. Methods In this study, infrared counters were used to monitor visitor use of a public natural park in southern Quebec, Canada. A risk index representing the probability of encounters between humans and infected vectors was constructed. This was done by combining the intensity of visitor trail use and the density of infected nymphs obtained from field surveillance. Patterns of risk were examined using spatial cluster analysis. Digital forest data and park infrastructure data were then integrated using spatially explicit models to test whether encounter risk levels and its components vary with forest fragmentation indicators and proximity to park infrastructure. Results Results suggest that, even at a very fine scales, certain landscape features and infrastructure can be predictors of risk levels. Both visitors and Borrelia burgdorferi-infected ticks concentrated in areas where forest cover was dominant, so there was a positive association between forest cover and the risk index. However, there were no associations between indicators of forest fragmentation and risk levels. Some high-risk clusters contributed disproportionately to the risk distribution in the park relative to their size. There were also two high-risk periods, one in early summer coinciding with peak nymphal activity, and one in early fall when park visitation was highest. Conclusions Here, we demonstrate the importance of integrating indicators of human behaviour visitation with tick distribution data to characterize risk patterns for tick-borne diseases in public natural areas. Indeed, understanding the environmental determinants of human-tick interactions will allow organisations to deploy more effective risk reduction interventions targeted at key locations and times, and improve the management of public health risks associated with tick-borne diseases in public spaces.

Lyme borreliosis (LB) is the most common tick-borne disease (TBD) in Germany. In Bavaria, the average annual incidence of reported cases was 34.3 cases per 100,000 inhabitants between 2013 and 2020, although case numbers were presumed to be substantially higher. Since no vaccine against LB is currently available, prevention focuses on individual protection measures. This study aims to address knowledge, attitudes, and behaviours among LB cases, a population group at increased exposure to ticks, tick bites and repeated infections.We invited Bavarian LB cases reported between weeks 23 and 35 in 2019 to participate in a questionnaire study. Questions included socio-demographic characteristics, experiences with TBDs, potential tick exposures, details of the recent episode of LB, and knowledge, attitudes, and behaviours regarding TBDs and protection measures.Among the 377 participants, 300 were adults/adolescents, 77 were children (

ABSTRACTThe emergence of Anaplasma bovis or A. bovis-like infection in humans from China and the United States of America has raised concern about the public health importance of this pathogen. Although A. bovis has been detected in a wide range of ticks and mammals in the world, no genome of the pathogen is available up to now, which has prohibited us from better understanding the genetic basis for its pathogenicity. Here we describe an A. bovis genome from metagenomic sequencing of an infected goat in China. Anaplasma bovis had the smallest genome of the genus Anaplasma, and relatively lower GC content. Phylogenetic analysis of single-copy orthologue sequence showed that A. bovis was closely related to A. platys and A. phagocytophilum, but relatively far from intraerythrocytic Anaplasma species. Anaplasma bovis had 116 unique orthogroups and lacked 51 orthogroups in comparison to other Anaplasma species. The virulence factors of A. bovis were significantly less than those of A. phagocytophilum, suggesting less pathogenicity of A. bovis. When tested by specific PCR assays, A. bovis was detected in 23 of 29 goats, with an infection rate up to 79.3% (95% CI: 64.6% ∼94.1%). The phylogenetic analyses based on partial 16S rRNA, gltA and groEL genes indicated that A. bovis had high genetic diversity. The findings of this study lay a foundation for further understanding of the biological characteristics and genetic diversity of A. bovis, and will facilitate the formulation of prevention and control strategies.

The abundant and widely distributed deermice Peromyscus leucopus and P. maniculatus are important reservoirs for several different zoonotic agents in North America. For the pathogens they persistently harbor, these species are also examples of the phenomenon of infection tolerance. In the present study a prior observation of absent expression of the high-affinity Fc immunoglobulin gamma receptor I (FcγRI), or CD64, in P. leucopus was confirmed in an experimental infection with Borreliella burgdorferi, a Lyme disease agent. We demonstrate that the null phenotype is attributable to a long-standing inactivation of the Fcgr1 gene in both species by a deletion of the promoter and coding sequence for the signal peptide for FcγRI. The Fcgr1 pseudogene was also documented in the related species P. polionotus. Six other Peromyscus species, including P. californicus, have coding sequences for a full-length FcγRI, including a consensus signal peptide. An inference from reported phenotypes for null Fcgr1 mutations engineered in Mus musculus is that one consequence of pseudogenization of Fcgr1 is comparatively less inflammation during infection than in animals, including humans, with undisrupted, fully active genes.

Tick-borne infectious agents (TBIAs) include several bacteria and protozoa that can infect vertebrates, including humans. Some of these agents can cause important diseases from both a public health perspective, such as Lyme disease, and from an animal health and production viewpoint, such as Texas fever. In Chile, several studies have assessed the presence of tick-borne disease agents in vectors and mammal hosts, mainly in the northern regions, but few studies have assessed the presence of these agents in Central and Southern Chile. This study aimed to assess the presence of three groups of TBIAs--Borrelia, Anaplasmataceae, and Piroplasmida--in cricetid rodents of Central and Southern Chile. A total of 207 specimens from 13 localities between the O'Higgins and Los Lagos regions were captured. DNA was extracted from the liver and spleen, and subsequently underwent polymerase chain reaction (PCR) amplification targeting the 16S rRNA, flaB, and 18S rRNA genes to detect DNA from Borrelia, Anaplasmataceae, and Piroplasmida, respectively. Although no DNA from these TBIAs was detected, the DNA extraction process was validated by optimal DNA purity ratios (an A260/A280 ratio within the 1.6-2.0 range) and successful internal control amplification in all samples. These results, in addition to findings from previous reports, suggest a very low prevalence of these TBIAs in the rodent population studied. Further research into the factors influencing the presence of these agents and their vectors will provide insight into the reasons underlying this low prevalence. [ABSTRACT FROM AUTHOR]

Tick-borne diseases (TBDs) pose a rapidly growing threat to public health. The incidence of TBDs is on the rise, necessitating a comprehensive understanding of the risk factors beyond demographic considerations. This brief report combines a preliminary review of the literature with geographical case mapping to identify the various factors influencing TBD risk. The report highlights the vulnerability of outdoor workers, the importance of outdoor activities, and the role of education in adopting preventive behaviors. Pet ownership and interactions with animals are also associated with an increased risk. The state of Illinois is used as a case study for this report, revealing regional variations in TBD incidence, and linking them to agricultural practices, forested areas, and park accessibility. These findings inform recommendations for targeted prevention strategies, emphasizing the need for detailed geographical data to enhance public health efforts in curbing TBD incidence and risk. [ABSTRACT FROM AUTHOR]

Background: This study aimed to analyze the correlation between the cycle threshold (Ct) values of severe fever with thrombocytopenia syndrome (SFTS) virus small (S) and middle (M) segments and the SFTS viral load, aiming to estimate the initial viral load and predict prognosis in the early clinical course. Method: A retrospective study was conducted with confirmed SFTS patients at Jeju National University Hospital (2016–2022). Patients were categorized into non-fatal and fatal groups. Results: This study included 49 patients with confirmed SFTS (non-fatal group, n = 42; fatal group, n = 7). A significant negative correlation (−0.783) was observed between the log SFTS viral load and Ct values (p < 0.001). This negative correlation was notably stronger in the fatal group (correlation coefficient −0.940) than in the non-fatal group (correlation coefficient −0.345). Conclusion: In this study, we established a correlation between SFTS viral load and Ct values for estimating the initial viral load and early predicting prognosis. These results are expected to offer valuable insights for SFTS patient treatment and prognosis prediction. [ABSTRACT FROM AUTHOR]

Considering that co-feeding transmission depends on the loads of infected ticks on each host, we develop a tick-borne disease dynamics model with co-feeding transmission probability peaking at an intermediate level of infected tick loads. We stratify tick and host population by their infection status and divide the vector population in terms of infection status and post-egg stages (larvae, nymphs and adults). We use the tick population dynamics and disease spread basic reproduction numbers and co-feeding transmission characteristics to describe the disease endemic structure, and show, for the first time, that density-dependent co-feeding transmission provides a novel mechanism for bi-stability. Numerical simulations based on parameters from laboratory and fields data confirm the possibility of bi-stability in biologically realistic settings, and sensitivity analyses show that the nymphal tick load value at which the co-feeding transmission probability reaches the maximum impacts most significantly on the stable endemic equilibrium value. [ABSTRACT FROM AUTHOR]

Rocky Mountain spotted fever (RMSF) is an international and quintessential One Health problem. This paper synthesizes recent knowledge in One Health, binational RMSF concerns, and veterinary and human medical perspectives to this fatal, reemerging problem. RMSF, a life-threatening tick-borne disease caused by the bacterium Rickettsia rickettsii, emerged during the first decade of the 21st century in impoverished communities in the southwestern US and northern Mexico. Lack of an index of suspicion, delay in diagnosis, and delayed initiation of antibiotic treatment contribute to fatality. Campaigns targeting dog neutering, restraint to residents' properties, and on-dog and on-premises treatment with acaricides temporarily reduce prevalence but are often untenable economically. Contemporary Mexican RMSF is hyperendemic in small communities and cities, whereas epidemics occur in the western US primarily in small tribal communities. In in both locations, the epidemics are fueled by free-roaming dogs and massive brown dog tick populations. In the US, RMSF has a case fatality rate of 5% to 7%; among thousands of annual cases in Mexico, case fatality often exceeds 30%.1,2 Numerous case patients in US border states have recent travel histories to northern Mexico. Veterinarians and physicians should alert the public to RMSF risk, methods of prevention, and the importance of urgent treatment with doxycycline if symptomatic. One Health professionals contribute ideas to manage ticks and rickettsial disease and provide broad education for the public and medical professionals. Novel management approaches include vaccine development and deployment, acaricide resistance monitoring, and modeling to guide targeted dog population management and other interventions. [ABSTRACT FROM AUTHOR]

Co-infections with multiple tick-borne pathogens have been a public health issue due to their significant impacts on human and animal health. Here, we develop a novel delay differential system model to describe the long-term co-infection dynamics through co-feeding transmission involving incompetent hosts. We distinguish two cases depending on the tick life cycle, which acts as a delay in the tick population model. With a small delay, our equilibrium analysis gives sharp conditions for the occurrence of extinction, single-pathogen establishment, pathogen invasion, and pathogen co-existence. We develop a cascading argument and use the invasion reproduction number to characterize the global dynamics of co-infection. With a large delay, we characterize the co-infection dynamics as extinction and pathogen co-existence as a globally attractive periodic solution, depending on the invasion reproduction number calculated using the next-generation operator approach. Our numerical trials guided by our global convergence (to periodic solutions) results illustrate a new and interesting phenomenon: the co-infection transmission outcomes are sensitive to the variation of the developmental delay (which is affected by the climatic conditions) when the tick population converges to a periodic solution bifurcated from a co-existence equilibrium and when the co-infection basic reproduction number is, with the onset of Hopf bifurcation, close to the threshold. [ABSTRACT FROM AUTHOR]

Case series summary: This case series describes six cases involving seven cats naturally infected with Cytauxzoon felis in Indiana, USA. Medical records were retrospectively reviewed and all available information on signalment, history, clinical and diagnostic findings, treatment, outcome and pathology was reported. Cats infected with C felis were domestic shorthairs, were aged between 2 and 9 years and all but one of the cats were male. The seven infected cats originated from five counties in southwestern Indiana. Six of seven cats were found to have acute cytauxzoonosis based on clinical signs, gross pathologic lesions, observation of C felis in tissues and/or detection of C felis DNA. One cat was identified as a subclinical survivor cat with no known clinical history of cytauxzoonosis. Relevance and novel information: The reported cases are the first confirmed reports of acute and chronic cytauxzoonosis in cats from Indiana and document an expansion in the range of C felis. Veterinary practitioners in Indiana should consider infection with C felis as a differential diagnosis for cats that present with fever, inappetence, lethargy, depression, dehydration, dyspnea, hemolytic crisis, anorexia or icterus. Administration of approved acaricides to cats currently offers the best protection and control against C felis infection. [ABSTRACT FROM AUTHOR]

Background: Infectious diseases are emerging across temperate regions of the world, and, for some, links have been made between landscapes and emergence dynamics. For tick-borne diseases, public parks may be important exposure sites for people living in urbanized areas of North America and Europe. In most cases, we know more about the ecological processes that determine the hazard posed by ticks as disease vectors than we do about how human population exposure varies in urban natural parks. Methods: In this study, infrared counters were used to monitor visitor use of a public natural park in southern Quebec, Canada. A risk index representing the probability of encounters between humans and infected vectors was constructed. This was done by combining the intensity of visitor trail use and the density of infected nymphs obtained from field surveillance. Patterns of risk were examined using spatial cluster analysis. Digital forest data and park infrastructure data were then integrated using spatially explicit models to test whether encounter risk levels and its components vary with forest fragmentation indicators and proximity to park infrastructure. Results: Results suggest that, even at a very fine scales, certain landscape features and infrastructure can be predictors of risk levels. Both visitors and Borrelia burgdorferi-infected ticks concentrated in areas where forest cover was dominant, so there was a positive association between forest cover and the risk index. However, there were no associations between indicators of forest fragmentation and risk levels. Some high-risk clusters contributed disproportionately to the risk distribution in the park relative to their size. There were also two high-risk periods, one in early summer coinciding with peak nymphal activity, and one in early fall when park visitation was highest. Conclusions: Here, we demonstrate the importance of integrating indicators of human behaviour visitation with tick distribution data to characterize risk patterns for tick-borne diseases in public natural areas. Indeed, understanding the environmental determinants of human-tick interactions will allow organisations to deploy more effective risk reduction interventions targeted at key locations and times, and improve the management of public health risks associated with tick-borne diseases in public spaces. [ABSTRACT FROM AUTHOR]

Background Emerging tick-transmitted illnesses are increasingly recognized in the United States (US). To identify multiple potential tick-borne pathogens in patients from the Upper Midwest and Northeast US with suspected anaplasmosis, we used state-of-the-art methods (polymerase chain reaction [PCR] and paired serology) to test samples from patients in whom anaplasmosis had been excluded. Methods Five hundred sixty-eight patients without anaplasmosis had optimal samples available for confirmation of alternative tick-borne pathogens, including PCR and/or paired serology (acute-convalescent interval ≤42 days). Results Among 266 paired serology evaluations, for which the median acute-convalescent sampling interval was 28 (interquartile range, 21–33) days, we identified 35 acute/recent infections (24 [9%] Borrelia burgdorferi ; 6 [2%] Ehrlichia chaffeensis/Ehrlichia muris subsp eauclairensis [ EC/EME ]; 3 [1%] spotted fever group rickettsioses [SFGR], and 2 [<1%] Babesia microti) in 33 (12%) patients. Two had concurrent or closely sequential infections (1 B burgdorferi and EC/EME , and 1 B burgdorferi and SFGR). Using multiplex PCR and reverse-transcription PCR, we identified 7 acute infections (5/334 [1%] Borrelia miyamotoi and 2/334 [1%] B microti) in 5 (1%) patients, including 2 with B microti – B miyamotoi coinfection, but no Borrelia mayonii , SFGR, Candidatus Anaplasma capra, Heartland virus, or Powassan virus infections. Thus, among 568 patients with ruled-out anaplasmosis, 38 (6.7%) had ≥1 agent of tick-borne illness identified, with 33 patients (35 infections) diagnosed by paired serology and 5 additional patients (7 infections) by PCR. Conclusions By identifying other tick-borne agents in patients in whom anaplasmosis had been excluded, we demonstrate that emerging tick-borne infections will be identified if specifically sought. [ABSTRACT FROM AUTHOR]

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Copyright of Acta Veterinaria Brasilica is the property of Acta Veterinaria Brasilica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)