Scabies in the Philippines: A Secondary Analysis of Local Patient Registries

Abstract

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%]).

A Systematic Review of Epidemiologic Studies on Scabies in the Philippines

“…36 This coincides with the peak months in the previous epidemiological study on scabies from local patient registries. 12 Our findings for clinic-based retrospective chart review (all age groups) studies showed moderate prevalence (4.0 to 6.8%), which is similar to a study included in the systematic review by Khoobdel et al (2023) in a dermatology clinic in Hormozgan, Iran (4.04%). 37 As in our study where prevalence in children in orphanages had high prevalence (39%), institutionalized individuals (i.e., prisoners in Hormozgan, Iran) similarly showed high prevalence: 56.7%.…”

“…There was an earlier publication based on this protocol that reviewed two Philippine medical society patient registries. 12 We included studies that reported on prevalence/ incidence (systematic reviews, cross-sectional studies, cohort studies, case series, studies with clinic/registry/census data) of patients diagnosed with scabies in the Philippines, regardless of setting, age, sex, severity, type, or comorbidity. We excluded narrative reviews, commentaries, and conference proceedings or abstracts.…”

“…11 We published a secondary analysis of two Philippine medical society patient registries, which showed the prevalence of scabies to be 5.15% (IQR 2.35) among patients (mostly outpatients) seen at selected dermatology departments affiliated with the Philippine Dermatological Society, and 0.05% (IQR 0.02) among inpatients admitted in Philippine Pediatric Society-affiliated hospitals. 12 As part of the recommended framework by the WHO expert panel for scabies in 2019, prioritizing the mapping of disease burden is essential. This includes defining areas with prevalent scabies infections for possible implementation of mass drug administration.…”

Economic Evaluation of Oral Ivermectin, Alone or in Combination with Permethrin, versus Permethrin, in the Treatment of Classic Scabies in the Philippine Setting

“…6 Scabies ranked fourth among new consults with an overall median percentage of 5.15% (IQR 2.35) from 2010-2021 in dermatology training outpatient departments (OPDs) in the Philippines based on the Philippine Dermatological Society Health Information System. 7 The most common first-line of treatment for scabies are topical prescription scabicides such as permethrin 5%, benzyl benzoate 25%, or crotamiton 10%. 8 Most drugs work through a neurotoxic mechanism either by delayed repolarization (permethrin, malathion, lindane) or hyperpolarization (ivermectin) in neuromuscular synapses, thereby paralyzing and killing the mites.…”