As the coronavirus pandemic is still threatening and killing people all over the world, a group of more than 400 French dermatologists compared notes and noticed that some patients, who were later diagnosed with COVID-19, came to see them with unusual symptoms: redness and swelling of the tip of their fingers, sometimes associated with pain as if they had frostbite (the medical term is acrosyndrome).

Some of the patients had small itchy eczema-like lesions on their extremities (the medical term is dyshydrosis). Those symptoms appeared suddenly without being exposed to cold or any other possible culprit, and they were temporary.