The Dermatologic Burden of Flooding: A Systematic Review of Epidemiology, Clinical Manifestations, and Management in a Warming World

Anthropogenic climate change has intensified the frequency of catastrophic flooding, contributing to a complex array of public health challenges. Although acute trauma dominates the initial response, the post-disaster dermatological burden remains an under-reported driver of morbidity. This systematic review characterizes the pathophysiology of flood-associated dermatoses into three clinical categories: water-contact injuries, displacement-related conditions, and environmental aeroallergen-induced exacerbations. We conducted a systematic, mechanistic synthesis of 12 epidemiological studies (including retrospective cohorts, time-series, and case-crossover designs) from the USA, Brazil, France, Pakistan, China, Taiwan, Vietnam, Cambodia, and South Korea. Spanning over 71 million patient encounters, the data were rigorously appraised using JBI Critical Appraisal tools. Analysis reveals three distinct clinical phases. First, in high-resource settings, data indicate no significant increase in Staphylococcus aureus infections, although mucosal risks (e.g., leptospirosis, Aeromonas) and chemical irritant dermatitis are observed. Second, flood-associated humidity and wind independently drive acute atopic dermatitis flares (odds ratio [OR] 1.14) and allergic rhinitis, independent of direct water contact. Third, shelter overcrowding drives a delayed surge of communicable infestations (e.g., scabies, pediculosis) approximately 1 week post-disaster. Flood-associated skin conditions are heterogeneous. Preparedness requires moving from non-specific antibiotic prophylaxis to a stratified response involving targeted mucosal monitoring, ectoparasite control in shelters, and anti-inflammatory therapy for atopic populations. (Figure presented.).