A new study has found that a skin condition known as Covid toes is most likely a side effect of the immune system’s response to fighting off the virus.
The symptom results in chilblain-like inflammation and redness on the hands and feet, with the condition sometimes lasting for months at a time.
It typically develops within a week to four weeks of being infected and can result in toes and fingers becoming swollen or changing colour.
Researchers behind the study, which has been published in the British Journal of Dermatology, examined 50 participants with Covid toes and 13 with similar chilblains lesions that arose before the pandemic.
They found one mechanism behind both types of the condition involved the body generating an immune response with high levels of certain autoantibodies, which mistakenly target and react with a person’s own cells and tissues as well as the invading virus.
They also found an overlap with type I interferon, a key protein in the antiviral response.
In addition to the immune system, cells lining blood vessels which supply the affected areas also appeared to play a critical role in the development of Covid toes and chilblains.
Senior author of the study, Dr Charles Cassius, said the research provided a deeper understanding of the condition.
“The epidemiology and clinical features of chilblain-like lesions have been extensively studied and published, however, little is known about the pathophysiology involved,” he said.
“Our study provides new insights.”