The prevalence of scabies in Monrovia, Liberia: A population-based survey

Author summary Scabies is an infestation with a microscopic mite which affects many people living in low-resource tropical countries. It causes intense itching, which can lead to complications through bacterial infection and poor quality of life. To help develop global scabies control programmes, we need a better understanding of how common it is across different tropical settings. We conducted a survey to assess the burden of scabies and bacterial skin infection in a random sample of people living in a community in Monrovia, Liberia. Information about participants and their household were collected and their skin was examined; those with skin conditions were asked about its impact on quality of life. We examined 1,318 participants and found that almost 10% of people had scabies. Scabies was more common in young children and more common in male children than female children. We found that there was a large impact on quality of life due mostly to the itching that scabies causes and to people feeling embarrassed or sad because of their skin condition. This scabies survey is one of the first conducted across all age groups in recent years in sub-Saharan Africa and indicates a substantial burden and impact on quality of life. More work is needed to understand how common scabies is in different settings and the impact that different treatment strategies may have. Scabies is known to be a public health problem in many settings but the majority of recent data is from rural settings in the Pacific. There is a need for high quality data from sub-Saharan Africa and peri-Urban settings to inform scale up of scabies control efforts. There have been anecdotal reports of scabies being a public health problem in Liberia but robust data are lacking. We conducted a cross-sectional cluster-randomised prevalence survey for scabies in a peri-urban community in Monrovia, Liberia in February-March 2020. Participants underwent a standardised examination conducted by trained local health care workers. Health related quality of life (HRQoL) was assessed using age-appropriate versions of the dermatology life quality index (DLQI). Prevalence estimates were calculated accounting for clustering at community and household levels and associations with key demographic variables assessed through multivariable random-effects logistic regression. 1,318 participants from 477 households were surveyed. The prevalence of scabies was 9.3% (95% CI: 6.5-13.2%), across 75 (19.7%) households; impetigo or infected scabies prevalence was 0.8% (95% CI: 0.4-1.9%). The majority (52%) of scabies cases were classified as severe. Scabies prevalence was lower in females and higher in the youngest age group; no associations were found with other collected demographic or socio-economic variables. DLQI scores indicated a very or extremely large effect on HRQoL in 29% of adults and 18% of children diagnosed with scabies. Our study indicates a substantial burden of scabies in this peri-Urban population in Liberia. This was associated with significant impact on quality of life, highlighting the need for action to control scabies in this population. Further work is needed to assess the impact of interventions in this context on both the prevalence of scabies and quality of life.