People may be spending more time looking at their toes these days learning that an unusual symptom that has been dubbed COVID toes started appearing in people who have tested positive for the virus. An international registry is now tracking the effects of the disease on the skin, helping dermatologists learn more. 

One of the leaders of this effort has an important message if you find these lesions: Do not panic, but be mindful that you could be infectious. It may be the only symptom you get from COVID-19. It may also have nothing at all to do with the virus.

Dr. Esther Freeman, Assistant Professor of Dermatology at Harvard Medical School and a board-certified dermatologist. She's also directing the COVID-19 Dermatology Registry, an international collaboration to track skin manifestations of the disease.

Freeman says the registry has received more than 300 cases of a variety of dermatological manifestations from 21 countries. Only certified medical professionals -- not the general public -- can contribute to the registry.

COVID toes
A teenage patient's foot as pictured on April 3, 2020, at the onset of the skin condition being informally called "COVID toes."
Dr. Amy Paller

Freeman says she is not surprised to see rashes come with COVID-19. Various skin manifestations commonly happen with viruses such as measles or chickenpox. But the COVID toes, which resemble a condition called Pernio or Chilblains, was unexpected.

"Typically in the past, we haven't heard a lot about Pernio-like reactions in the feet in other viruses. It's not that it's never happened, but it's not a common viral reaction that we usually see," Freeman said.

Pernio is usually an inflammatory reaction to cold temperatures and is seen in the winter or early spring. 

"What's unusual here is that we're seeing it in patients who are in warm climates or patients who have been sheltering in place inside in warmer environments," Freeman said.

COVID toes are being seen in both children and adults.

Freeman stresses that if these lesions appear on your toes, do not panic and go rushing to the emergency room. While some patients with COVID toes have gotten very ill with other symptoms, others have shown no symptoms other than the lesions.

"I think it is important to talk to your board-certified dermatologist or to your health care provider and get evaluated," Freeman said, noting that the lesions could be developing for reasons other than COVID-19. The doctor or dermatologist can go through your medical history to see if something else may be the cause.

But if the cause can't be determined, or if you can't get a COVID-19 test, then Freeman says you should self-isolate as a precaution. 

"We don't know that you're infectious. Some of our patients seem to be getting this as a late-stage disease finding and they may no longer be infectious, but some of our patients are developing this and they are ... lab-test positive for what we assume is active infection," Freeman said.

Freeman stresses that these lesions could be the only symptom someone with COVID-19 encounters, or it could be one of many. 

About half the entries in the registry are for skin reactions other than COVID toes. Some are morbilliform, which is a rash that looks like measles but can be associated with multiple types of viruses or may be a reaction to medications. Freeman says they are also seeing cases of hives, which is normally an allergic reaction.

Freeman notes that these represent only the cases in the registry and it should not be assumed that all COVID-19 patients will develop such rashes and lesions.

Freeman says she has seen more toe lesions in the past two weeks than she has in her entire career.

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