Prevalence and determinants of scabies: a global systematic review and meta-analysis

Abstract

Background Scabies is a neglected skin disease that disproportionately affects people from resource poor and overcrowded countries. Global data on prevalence and risk factors are limited. Methods Databases (PubMed, Scopus and Google Scholar) were accessed to identify observational studies about scabies published between 2000 and 2023. Results were pooled to estimate prevalence and identify factors which explained between-study heterogeneity. Odds ratios, risk of bias, subgroup analyses and meta-regression were used to describe variation in effect size and heterogeneity based on country-level demographic and economic variables. Findings Fifty-four studies yielded a pooled prevalence of 14.0% (95% confidence interval [CI] 11.4-17.1%) with substantial heterogeneity (I^2=100%; τ^2=0.77). Prevalence was higher in Oceania (18.2%; 95% CI 14.1-23.1) compared to other regions. Pooled risk factors for scabies showed significant associations for behavioral factors including contact with someone with itch (odds ratio [OR] 9.26; 95% CI 2.94-29.2), no use of soap (OR 3.42; 95% CI 2.80-4.18), infrequent bathing (OR 2.68; 95% CI 1.76- 4.08), bed-sharing (OR 2.57; 95% CI 1.33-4.96), clothes sharing (OR 2.40; 95% CI 1.39- 4.13), treated water source (OR 2.29; 95% CI 1.67-3.15) and presence of pets (OR 2.19; 95% CI 1.54-3.11). Socio-economic factors were not convincingly associated with scabies prevalence. Conclusion Prevalence of scabies is associated with geographic location and behavioural factors, but not between-country socioeconomic status. This study identifies risk factors for which targeted behavioural interventions addressing interpersonal interaction, personal hygiene practices and specific treatments related to scabies create the potential to reduce scabies disease burden.