Massive Scabies Outbreak In Rohingya Refugee Camps, Cox'S Bazar: Epidemiology And Impact Of A Mass Drug Administration (Mda) Campaign - A Retrospective Study

BackgroundSince 2021, Rohingya refugee camps in Coxs Bazar, Bangladesh, have experienced a significant and concerning increase in the prevalence of scabies. In response to the massive outbreak, an extensive Mass Drug Administration (MDA) campaign was conducted from November 29, 2023, to February 01, 2024. ObjectivesThe objectives of the study were: a) to determine the epidemiological characteristics of the scabies outbreak in the Rohingya refugee camps, including magnitude, age-sex distribution, and attack rate; and b) to evaluate the impact and durability of MDA in reducing the burden of scabies in the refugee camps. MethodologyThis was a retrospective observational study that utilized deidentified and anonymized data from 35 health facilities of the International Organization for Migration (IOM) spanning the period from January 1, 2021, to December 31, 2024. ResultsA total of 384,852 cases of scabies were reported, with an overall attack rate of 5,562.59 scabies cases per 10,000 population over 4 years. Females had a slightly higher case proportion (53.51%) and attack rate (ARR: 1.104, p < 0.001). Children under 5 years (36.31%) had the highest burden and attack rate, about twice the overall attack rate. Using this age group as reference, the attack rate declined significantly with increasing age, 5,561.85 among adolescents (ARR: 0.496, p < 0.001) to 4,377.88 among individuals over 60 years (ARR: 0.390, p < 0.001). 77% of the cases were reported among the Rohingya refugees; however, the attack rate was higher among host communities (7,721.34 per 10,000 vs. 5,138.24 per 10,000 among refugees). Overall, 5.80% of scabies cases were associated with secondary bacterial infections. Interrupted time series (ITS) analysis showed a sharp decline in scabies cases (from 1,885 cases per week to 0, p < 0.001) following the initiation of MDA. The decline caused by MDA persisted for 6 months, after which an upward trend was observed (with an increase of 72.04 cases/ per week). ConclusionThe study revealed an extremely high burden of scabies among the Rohingya refugees and the adjacent host community. MDA was an effective approach for a rapid and substantial reduction of the disease burden. However, the impact cannot be sustained unless the underlying factors of the scabies outbreak are addressed.