Effects of the COVID-19 pandemic on head lice and scabies infestation dynamics: a population-based study in France.

BACKGROUND: Lockdowns and physical distancing have dramatically limited the circulation of SARS-CoV-2 and other common communicable infections. However, little is known about their impact on head lice and scabies.

AIM: To assess the impact of the 2020 French National lockdowns (17 March-11 May 2020, and 30 October-15 December 2020) and physical distancing recommendations (from February 2020) on the dynamics of head lice and scabies infestations.

METHODS: The weekly sales of topical head lice treatments, topical scabies treatments and oral ivermectin were extracted from the database of the healthcare science company IQVIA (60% of all French retail pharmacies) and analysed over a 5-year period (March 2016-December 2020). A periodic regression model was fitted to drug sales before the COVID-19 period (2016-2019) and extrapolated to compare the observed sales in 2020 to the expected sales.

RESULTS: A decrease of the sales of tracer topical treatments for head lice and scabies was observed from March 2020, synchronously with the first French national lockdown. For the period March-December 2020, the mean reduction in observed vs. expected sales for head lice and scabies topical treatments was 44% and 14%, respectively. By contrast, although there was an observed decrease in oral ivermectin sales after March 2020, it was much lower (4%), probably because of studies reporting the potential positive effects of this drug on COVID-19 infection.

CONCLUSION: COVID-19 lockdown and physical distancing reduce circulation of head lice and scabies in France. Further studies are needed to assess the long-term impact of these social behaviour changes.