A systematic review of epidemiologic studies on scabies in the Philippines

Background and Objective@#Scabies is the second most common cause of disability due to skin disease in the Philippines. However, there were no cited studies in Global Burden of Disease 2019 and the disability-adjusted life years (DALY) computations were most likely based on statistical modelling. The Philippine Department of Health has embarked on a program to estimate the disease burden of priority diseases in the country, which include scabies. The last nationwide prevalence survey was 23 years ago. This systematic review aimed to estimate the prevalence or incidence of scabies in the Philippines. @*Methods@#We searched PubMed, Scopus, Herdin, and Philippine Health Research Registry (search date October 2022) for studies on prevalence/incidence (including systematic reviews, cross-sectional studies, cohort studies, case series, registry or census studies) of patients diagnosed with scabies in the Philippines. We excluded narrative reviews, commentaries, and conference proceedings or abstracts. Two reviewers independently screened titles and abstracts, assessed full text reports for eligibility, appraised the quality of included studies, and collected data using a pretested data extraction form. We did not pool studies due to clinical heterogeneity but plotted the individual studies in a forest plot with prevalence estimates and confidence intervals. We reported the median and interquartile range for entire group or relevant subgroups (age, setting) of studies. We used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to assess the certainty of evidence.@*Results@#We included nine studies (N=79,065). Most were clinic-based prevalence studies, retrospective chart reviews, conducted in dermatology outpatient clinics, Metro Manila area, and on pediatric populations. Prevalence of scabies was moderate (i.e., between 2 and 10%), ranging from 2.75% (national prevalence survey) to 6.8% (communitybased review), to high (> 10%) among pediatric patients in clinic-based retrospective chart reviews (29 to 36%) and institution-based surveys (39.0% to 45%), and a tertiary government university training hospital dermatology clinic (22.9%). The most affected age group was from 0 to 14 y/o, while males tended to have a higher prevalence than females. The cooler month of January had higher prevalence than the hotter month of June in one study. @*Conclusion@#Scabies is common in the Philippines, especially among children and elderly in institutional settings, and during the month of January. There is a need to do a national prevalence survey to identify high-risk areas and to monitor the prevalence of scabies, especially in crowded settings and vulnerable populations. This information can be used for estimating the burden of disease for scabies and guide appropriate health resource allocation.

Scabies in the Philippines: A secondary analysis of local patient registries

Background@#Scabies is the second most common cause of disability among skin diseases in the Philippines as of 2019. There is no large nationwide study describing the epidemiologic profile of scabies in the country. Objective. This study aimed to describe the demographic, seasonal, and geographic profile of scabies in the Philippines.@*Methods@# We compared secondary data of two local patient registries (Philippine Dermatological Society, PDS, 2010 to 2021; and Philippine Pediatric Society, PPS, 2009 to 2021) for reported cases of scabies in the Philippines. We reported the frequency and percentage distribution according to age, sex, month, year, and type of diagnosis, and region. @*Results@#The median annual frequency of scabies cases (mostly outpatient) for PDS (from year 2010) was 4087 (range ([QR], 342-6422 [3271.5]), while it was 183 (range [IQR], 64-234 [96.5]) (all inpatient) for PPS (from year 2009). There was a reduction to one-third (PDS) and one-fourth (PPS) of pre-pandemic numbers during the pandemic years (2020- 2021). The peak months for scabies cases were the cooler months: January (median, 12.1% of annual cases; range [IQR], 2.6%-31.4% [3.6%]) to February (median, 10.0% of annual cases; range [IQR], 1.5%-27.8% [2.5%]) based on PDS data, and November (median, 10.0% of annual cases; range [IQR], 0.0%-24.3% [7.0%]) to January (median, 9.0% of annual cases; range [IQR], 0.0%-24.3% [6.6%]) for PPS data. Overall, for PDS, age 1-4 years is the most affected age group (median, PDS, 17.5% of annual cases; range [IQR], 11.9%-25.4% [8.1%]), while it was the less than 1-yearolds (median annual cases, 48.9%; range [IQR], 29.1%-67.3% [13.20%]) among PPS pediatric population aged 0 to 18 years. Males (median, 53.9% of annual cases; range [IQR], 45.0%-67.2% [8.8%]) were more affected than females in PPS. While for PDS during earlier years (prior to 2015), males (median, 51.6% of annual cases from 2010 to 2014; range [IQR], 47.4%-52.9% [0.2%]) were more affected than females. However, males became less affected than females with median, 44.7% of annual cases from 2015 onwards (range [IQR], 43.4%-46.5% [1.2%]). NCR was the region with the highest frequency of cases in PPS (median, 52.6% of annual cases; range [IQR], 22.7%-75.0% [20.4%]). The 2nd most affected regions were Central/Eastern Visayas (34.2%, 2009-2013; range [IQR], 17.9%-54.1% [5.3%]), Bicol region (12%; 2014 to 2018; range [IQR], 17.9%-54.1% [7.4%]), Central Luzon (18%; 2019), Central/Eastern Visayas (29%, 2020), and Northern/Central Mindanao (17%, 2021). @*Conclusion@#Scabies was commonly seen in the younger age group, slightly more in females in the PDS, while slightly more among males in the PPS, in the cooler months of the year, and in the urbanized NCR.