Head Lice: A Revised View of the Impact of the COVID-19 Pandemic on Transmission and Prevalence

Head louse transmission is a regular occurrence among children when coming into close contact with others during social activities. During the Covid-19 pandemic most countries instituted lockdown periods resulting in isolation of children away from regular contacts, potentially restricting opportunities for louse transmission. Subsequently there were reports of reduced infestations in children at schools, compared with before the pandemic, with a parallel fall in sales of pediculicidal treatments in several countries beyond the longer-term decline in product sales observed over several years before the pandemic.

For this narrative review all literature linking Covid-19 and head lice were revisited and re-evaluated.

Despite the increased opportunity for elimination of infestations, some households with no outside contacts reported persistent incidence of head louse infestation and a review of the various studies suggests that most reported changes in head louse prevalence were relatively short lived or even illusory and in countries with low or middle incomes there was little or no difference in prevalence as a result of lockdowns.

Some aspects of the social distancing imposed in several countries during the pandemic appear to have continued to have some effect on social interactions of children, particularly in Western countries, with a commensurate slower recovery of head louse prevalence in some communities.