High IFN response to COVID-19 may cause chilblains, study suggests.
Chilblains seen during the COVID-19 outbreak may not be directly caused by the virus. Skin biopsies from patients with chilblains showed high levels of certain proteins, suggesting a strong immune response. However, testing showed low levels of interferon, a key immune protein. This challenges the idea that high interferon levels lead to negative COVID-19 tests. The presence of certain proteins in chilblains does not necessarily mean they are linked to the virus.