What can the hair tell us about COVID-19?

The novel viral pandemic coronavirus disease 2019 (COVID-19) has sparked uncertainties as to its origin, epidemiology and natural course. The study of the cutaneous manifestations of COVID-19 has evolved with the hope that they may be useful as markers for the disease, prognostication and pathogenic insights into the disease. With regard to the hair, clinicopathological correlations have remained elusive. More recently, androgenetic alopecia and grey hair have been proposed as cutaneous markers for elevated severity risk. So far, we have only observed postinfectious effluvium in a causal association with COVID-19. The onset and acuity of hair shedding depended on the clinical severity of disease. There was complete recovery of hair.