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Human adenovirus (HAdV), particularly the HAdV type 5 (HAdV-5), has been extensively utilized in the development of vector vaccines due to its high immunogenicity, good safety profile, and ease of propagation. However, one of the main challenges in its use is the presence of pre-existing immunity among vaccine recipients. Pre-existing neutralizing antibodies (NAbs) can prevent the uptake of HAdV-5 vectors and reduce vaccine efficacy. Hence, this study investigated the seroprevalence of NAbs against HAdV-5 in urban and rural regions of the Philippines. Luciferase-based neutralization assay was performed on 391 plasma/serum samples. Out of these samples, 346 or 88.5% were positive for HAdV-5 NAbs, and the majority of them (56.8%) had high titers against the virus. Among the regions included in this study, Bicol (Region V) had the highest seroprevalence rate (94.1%). Our findings show that a significant number of adults in the Philippines have pre-existing immunity against HAdV-5. This supports the recommendation that vaccination programs in the country should consider implementing vaccination techniques, such as a prime-boost regimen or addition of booster doses, to address the potential negative effects of pre-existing HAdV-5 immunity in the efficacy of adenoviral vector-based vaccines. [ABSTRACT FROM AUTHOR]

HPV infection is one of the most studied risk factors in cervical cancer—the second most common cancer site and cause of death due to cancer in the Philippines. However, there is a lack of population-based epidemiological data on cervical HPV infection in the Philippines. Local reports on co-infections with other lower genital tract pathogens, commonly reported globally, are also lacking, which emphasizes the need to increase efforts in targeting HPV prevalence, genotype, and distribution. Hence, we aim to determine the molecular epidemiology and natural history of HPV infection among reproductive-age Filipino women using a community-based prospective cohort design. Women from rural and urban centers will be screened until the target sample size of 110 HPV-positive women (55 from rural sites and 55 from urban sites) is reached. Cervical and vaginal swabs will be collected from all screened participants. For HPV-positive patients, HPV genotypes will be determined. One hundred ten healthy controls will be selected from previously screened volunteers. The cases and controls will comprise the multi-omics subset of participants and will be followed up after 6 and 12 months for repeat HPV screening. Metagenomic and metabolomic analyses of the vaginal swabs will also be performed at baseline, after 6 months, and after 12 months. The results of this study will update the prevalence and genotypic distribution of cervical HPV infection among Filipino women, determine whether the current vaccines used for HPV vaccination programs capture the most prevalent high-risk HPV genotypes in the country, and identify vaginal community state types and bacterial taxa associated with the natural history of cervical HPV infection. The results of this study will be used as the basis for developing a biomarker that can help predict the risk of developing persistent cervical HPV infection in Filipino women. [ABSTRACT FROM AUTHOR]

This study determined the psychosocial impact of COVID-19 on families of adult COVID-19 patients in isolation facilities in Metro Manila, Philippines. This prospective cohort study was conducted in COVID-19 healthcare facilities. Data collection was undertaken 2 weeks and 8 weeks after discharge. Logistic regression was performed to determine the socioeconomic and clinical factors influencing anxiety, depression, and family function. Based on HADS-P, 43.2% of the participants had anxiety symptoms, and 16.2% had depression symptoms 2 weeks after the discharge of their relative with COVID-19 infection. The prevalence of anxiety and depression significantly decreased to 24.3% and 5.4%, respectively, 8 weeks after discharge. The percentage of participants with a perceived moderate family dysfunction was 9.5% in the 2nd week and 6.8% in the 8th week post discharge. Participants with perceived severe family dysfunction increased from none to 4.1%. The most inadequate family resources for the participants were economic, medical, and educational resources. Patient anxiety (p = 0.010) and perceived inadequate family resources (p = 0.032) were associated with anxiety symptoms among family members. Patient anxiety (p = 0.013) and low educational attainment (p = 0.002) were associated with anxiety symptoms among family members 8 weeks after discharge. On the other hand, patient depression (p = 0.013) was a factor related to depressive symptoms among family members 2 weeks after discharge. This study provided an in-depth understanding of the mental health status of family members caring for relatives with COVID-19 infection. This can be used to guide healthcare professionals caring for COVID-19 patients and their family members. [ABSTRACT FROM AUTHOR]

Host-derived microRNAs (miRNAs) play important regulatory roles in schistosomiasis-induced hepatic fibrosis. This study analyzed selected serum miRNAs among Filipino schistosomiasis japonica patients with ultrasound (US)-detectable hepatic fibrosis. A prospective cohort study design with convenience sampling was employed from 2017 to 2019. The study sites were eight endemic barangays in Leyte, Philippines. Eligible chronic schistosomiasis patients with varying severities of hepatic fibrosis were enrolled in the cohort and serially examined at 6, 12, and 24 months from baseline. Baseline serum miR-146a-5p, let-7a-5p, miR-150-5p, miR-122-5p, miR-93-5p, and miR200b-3p were measured using RT-qPCR. A total of 136 chronic schistosomiasis patients were included in this prospective cohort study. Approximately, 42.6% had no fibrosis, 22.8% had mild fibrosis, and 34.6% had severe fibrosis at baseline The serum levels of the antifibrotic miR-146a (p < 0.0001), miR-150 (p = 0.0058), and let-7a (p < 0.0001) were significantly lower in patients with hepatic fibrosis while the profibrotic miR-93 (p = 0.0024) was elevated. miR-146a-5p (AUC = 0.90, 95% CI [0.84, 0.96], p < 0.0001) has the most promising potential to differentiate patients with (n = 78) versus without (n = 58) hepatic fibrosis. The baseline level of serum miR-146-5p was significantly different in patients with progressive fibrosis (n = 17) compared to those who never developed fibrosis (n = 30, p < 0.01) or those who had fibrosis reversal (n = 20, p < 0.01) after 24 months. These findings demonstrate the potential utility of serum miRNAs, particularly of miR-146a, as a supplementary tool for assessing hepatic fibrosis in chronic schistosomiasis japonica patients. [ABSTRACT FROM AUTHOR]

Schistosomiasis remains to ha/ve a significant public health impact in the Philippines. The Kato-Katz (K-K) technique is the reference standard and most used technique for definitive diagnosis of intestinal schistosomiasis for control programs in endemic regions. However, this has a very low sensitivity when applied in areas of low endemicity and patients with light infection. Hence, this study determined the diagnostic performance of immunological, molecular, parasitological, and ultrasonographic tests in diagnosing intestinal schistosomiasis in endemic municipalities in the Philippines. We performed a community-based cross-sectional study to determine the positivity of schistosomiasis in Leyte, Philippines. The diagnostic performance of five different detection techniques: (1) three stool K-K with duplicate smears; (2) soluble egg antigen IgG ELISA; (3) urine point-of-care circulating cathodic antigen (POC-CCA) test; (4) detection of Schistosoma japonicum circulating DNA (SjcDNA) in serum and urine samples; (5) focused abdominal ultrasound (US), were also obtained in this study. Multiple stool examinations enhanced the sensitivity of K-K from 26.2% (95% CI [16.4, 38.8]) with single stool to 53.8% (95% CI [41.1, 66.1]) and 69.2% (95% CI [56.4, 80.0]) with two and three stools from consecutive days, respectively. Among the SjcDNA nucleic acid amplification test (NAAT)-based detection assays, loop-mediated isothermal amplification (LAMP) PCR using sera had the highest sensitivity at 92.3% (95% CI [82.2, 97.1]) with LAMP consistently identifying more positive cases in both serum and urine samples. This study showed that single stool K-K, which remains the only diagnostic test available in most endemic areas in the Philippines, had low sensitivity and failed to identify most patients with light infection. SjcDNA detection assay and POC-CCA urine test were more sensitive than stool microscopy in detecting schistosomiasis. On the other hand, US was less sensitive than the widely utilized K-K technique in diagnosing schistosomiasis. This study emphasizes the need to revisit the use of single stool K-K in the surveillance and case detection of schistosomiasis in endemic areas of the Philippines. The availability of advanced and more sensitive diagnostic tests will help better control, prevent, and eliminate schistosomiasis in the country. [ABSTRACT FROM AUTHOR]

In recent years, the prevalence and infection intensity of Schistosoma japonicum in endemic areas of the Philippines have significantly decreased due to yearly population-based treatment strategies, yet transmission rates remain high and uninterrupted. An important indicator of active disease transmission is the presence of Schistosoma japonicum and its snail intermediate host Oncomelania hupensis quadrasi in freshwater habitats. In this study, we sought to apply a species-specific real-time PCR (qPCR) assay for the detection of S. japonicum and O. hupensis quadrasi in freshwater samples using environmental DNA approach that can complement the commonly utilized malacological survey in determining potential transmission foci in order to have a more effective snail surveillance strategy for schistosomiasis japonica in endemic areas. The newly developed assay was specific to S. japonicum and O. hupensis quadrasi with no amplification detected against non-target trematode Fasciola spp. and snails such as Lymnaea spp., Pomacea canaliculata, and Melanoides spp. that typically co-exist in the same environment. The assay effectiveness was determined using 19 environmental water samples collected from Northern Samar (N = 5 sites), Leyte (N = 11 sites) and Compostela Valley (N = 3 sites) and compared to malacological survey for determining O. hupensis quadrasi snail colonies and snail crushing to visualize S. japonicum cercariae. TaqMan qPCR targeting a short fragment of the cytochrome c oxidase subunit 1 (cox1) gene was positive for S. japonicum in 9 sites, for O. hupensis quadrasi in 9 sites, and for both S. japonicum and O. hupensis quadrasi in 5 sampling sites. Moreover, it was able to detect O. hupensis quadrasi in 3 out of 12 sites found negative and 6 out of 7 sites found positive through malacological survey, and in 4 of the 5 snail sites positive for snails with cercariae. Overall, this method can complement malacological surveys for monitoring of schistosomes in endemic areas of the Philippines, especially those with high risk of human infection. [ABSTRACT FROM AUTHOR]

Background: The perpetuation of schistosomiasis japonica in the Philippines depends to a major extent on the persistence of its intermediate host Oncomelania hupensis quadrasi, an amphibious snail. While the malacological survey remains the method of choice in determining the contamination of the environment as evidenced by snails infected with schistosome larval stages, an emerging technology known as environmental DNA (eDNA) detection provides an alternative method. Previous reports showed that O. hupensis quadrasi eDNA could be detected in water, but no reports have been made on its detection in soil. Methods: This study, thus focused on the detection of O. hupensis quadrasi eDNA from soil samples collected from two selected schistosomiasis-endemic barangays in Gonzaga, Cagayan Valley using conventional and TaqMan-quantitative (qPCR) PCRs. Results: The results show that qPCR could better detect O. hupensis quadrasi eDNA in soil than the conventional method. In determining the possible distribution range of the snail, basic edaphic factors were measured and correlated with the presence of eDNA. The eDNA detection probability increases as the pH, phosphorous, zinc, copper, and potassium content increases, possibly indicating the conditions in the environment that favor the presence of the snails. A map was generated to show the probable extent of the distribution of the snails away from the body of the freshwater. Conclusion: The information generated from this study could be used to determine snail habitats that could be possible hotspots of transmission and should, therefore, be targeted for snail control or be fenced off from human and animal contact or from the contamination of feces by being a dumping site for domestic wastes. [ABSTRACT FROM AUTHOR]

• Taxonomic classification, proposed origin and geographic spread of Oncomelania hupensis and genetic differentiation of Oncomelania hupensis quadrasi • Biology of Oncomelania hupensis quadrasi • Snail Control • Use of RS/GIS in Snail Research • Way Forward Oncomelania hupensis quadrasi is the snail intermediate host of Schistosoma japonicum in the Philippines. It was discovered by Dr. Marcos Tubangui in 1932 more than two decades after the discovery of the disease in the country in 1906. This review, the first for O. h. quadrasi , presents past and present works on the taxonomy, biology, ecology, control, possible paleogeographic origin of the snail intermediate host and future in research, control and surveillance of the snail. Extensive references are made of other subspecies of O. hupensis such as the subspecies in China for which majority of the advances has been accomplished. Contrasting views on whether the snail is to be considered an independent species of Oncomelania or as one of several subspecies of Oncomelania hupensis are presented. Snail control methods such as chemical methods using synthetic and botanical molluscicides, environmental manipulation and biological control are reviewed. Use of technologies such as Remote Sensing, Geographical Information System and landscape genetics is stressed for snail surveillance. Control and prevention efforts in the Philippines have consistently focused on mass drug administration which has proved inadequate in elimination of the disease. An integrated approach that includes snail control, environmental sanitation and health education has been proposed. Population movement such as migration for employment and economic opportunities and ecotourism and global climate change resulting in heavy rains and flooding challenge the gains of control and elimination efforts. Concern for possible migration of snails to non-endemic areas is expressed given the various changes both natural and mostly man-made favoring habitat expansion. [ABSTRACT FROM AUTHOR]

In the Philippines, ten NTDs are prevalent, but only six namely LF, schistosomiasis, STH, food-borne trematodiases, rabies and leprosy are considered to be of public health importance. The 81 provinces in the country are endemic for at least one of these NTDs. Others may be endemic for two or even more of these diseases. Since 2000, after the Philippines accepted and implemented the WHO guidelines for NTDs prevention, control and elimination, significant progress has been achieved in reducing the magnitude of NTDs endemic in the country. Since 2009, out of 46 filariasis-endemic provinces, the number of provinces that has eliminated LF has progressively increased so that by 2015, 76% are already LF-free. By 2019, only four provinces remain endemic for LF. For schistosomiasis, as of 2012, report from the Department of Health (DOH) put the number of high endemic provinces at 10, moderately endemic at 6 and low to elimination levels at 12. For STH, results of the National Parasite Survey in the Philippines among school-aged children conducted in 2015 by the Research Institute for Tropical Medicine, the research arm of the Philippine DOH, however, showed that the overall cumulative prevalence was 28.4% with a prevalence range between 7.1% and 67.4%. The figures are way above the <20% prevalence standard set by the World Health Organization. Control and prevention efforts for FBTs just gained traction with the call of WHO for elimination of NTDs in 2015. There is an urgent need to update information by an intensive national baseline survey that can validate previous data as well as generate new information on the magnitude of the FBT problem in the Philippines. For leprosy, elimination activities have been intensified in high prevalence areas and from 2009 to 2013, case detection and prevalence were sustained at <1.0 per 10,000 population. Rabies elimination activities have been effective that by 2011, only five regions out of 16 remained with the highest number of rabies cases. In a period of seven years from 2010 to 2017, the number of rabies-free provinces and municipalities increased from 3 to 49. Problems continue to hound the NTD programmes in the Philippines as priorities shift to more urgent health problems in a country that is weighed down not only by the triple burden of disease but serious health consequences of emergencies and disasters and the fast-growing population itself. Paradigm shifts are suggested to replace the traditional and conventional perspectives of control. These include change from disease approach to intervention approach to allow for integration of strategies targeting several NTDs and multisectoral, multidisciplinary approach requiring strong, viable and sustainable partnerships involving various agencies of the government, public and private sector, pharmaceuticals, academe, researchers, local government units and the endemic communities themselves. [ABSTRACT FROM AUTHOR]