[COVID-toes, a cutaneous sign of innate resistance to SARS-CoV-2].

Yatim, Ahmad; Gilliet, Michel

Since the beginning of the COVID-19 pandemic, dermatologists around the world have reported patients with chilblain-like skin lesions on their toes, called COVID-toes. Surprisingly, the majority of these patients do not develop COVID-19 symptoms, and their nasal swabs and serological tests are unable to confirm SARS-CoV-2 infection, despite a clear exposure to the virus. Recent evidence suggests that these patients mount a robust type I interferon response to SARS-CoV-2, making them resistant to the infection. Because chilblains are hallmarks of excessive type I interferons, COVID-toes may represent the skin expression of interferon-mediated resistance to SARS-CoV-2. Uncovering the molecular patho-mechanisms of COVID-toes may provide new avenues to promote SARS-CoV-2 resistance and control the COVID-19 pandemic.