As researchers continue studying different aspects of the COVID-19 pandemic, reports of unusual symptoms continue to emerge. One of the most surprising is a red or purplish rash and raised bumps that appear on the tips of the toes.
At first, this was thought to be an odd coincidence. But now, the research is starting to indicate that this symptom—which has been dubbed “COVID toes”—is actually linked to the virus. Just like COVID nails, COVID tongue, and hair loss.
The ‘COVID Toes’ Details
The latest research to strengthen the connection between COVID-19 and “COVID toes” comes from the British Journal of Dermatology.
In a small study published on October 5, researchers analyzed 63 people with redness and swelling in their hands and toes, also known as chilblain-like lesions (chilblains is a condition similar to frostbite that is caused by exposure to extremely cold temperatures).
According to researchers, fifty participants in the study tested positive for the coronavirus and had COVID toes. The remaining 13 study subjects actually had chilblains lesions.
In both groups, the researchers found that the symptoms were developed “as a result of an immune response containing high levels of certain auto-antibodies.” Most notably, the antibody called type I interferon.
Also playing an important role were the endothelial cells, which make up the thin membrane that lines the inside of blood vessels.
That’s a lot of medical jargon and science talk, but what does all of that mean? Essentially, the frostbite-like rashes that pop up on someone’s toes after they have COVID-19 may be a sign of a runaway immune response where the body attacks its own tissues.
As dermatologist Dr. Ife J. Rodney—founding director of Eternal Dermatology Aesthetics and Howard University professor—explains, it comes down to your body’s immune response to the virus.
“As with other viral infections, your body mounts an immune response in an attempt to fight off the COVID-19 virus,” Dr. Rodney told Health. “This immune response causes inflammation throughout your body that can present in a variety of different ways on the skin.”
She adds that Interferon is a protein involved in inflammation, which can cause red spots and rashes on the toes, and that can be itchy and painful.
“In COVID toes, the inflammation also damages small blood vessels in the toes, leading to a reddish-purple discoloration of your skin [usually seen in chilblains],” she says. “We are unsure why the COVID rash takes on this specific presentation, as it does not seem to be more common in the wintertime or related to cold exposure.”
Why Do Some People Get COVID Toes And Others Don’t?
According to Dr. Joshua Zeichner—the director of Cosmetic & Clinical Research in Dermatology at Mount Sinai Hospital in New York City—doctors and researchers haven’t figured out why some people get COVID toes while others don’t experience that symptom. But, it’s probably linked to the differences in our immune systems.
“The reason why some people experience these symptoms more than others is likely because of differences in the degree to which one person’s immune system reacts versus another person’s,” Dr. Zeichner told Health.
Infectious disease expert Dr. Amesh A. Adalja—a senior scholar at the John Hopkins Center for Health Security—told Health that people need to understand that COVID toes is not a common phenomenon. So if and when it does occur, you should seek immediate medical attention.
Doctors Started Seeing COVID Toes In April 2020
Even though COVID toes are just now being reported as a possible sign you have COVID-19, doctors first started seeing this symptom well over a year ago.
In an April 2020 press release, the General Council of Official Colleges of Podiatrists in Spain said they had begun “registering numerous cases of sick people, mainly children and young people, who had small dermatological lesions on their feet.”
Just like with everything else related to COVID, the appearance of COVID toes was quite inconsistent. Sometimes, they appeared in the absence of other symptoms. And sometimes, the COVID toes developed before other symptoms appeared.
Small studies and anecdotal cases of COVID toes have shown, so far, that these lesions are “purple colored” and they usually present themselves on the tips of the toes.
Oftentimes they cause itching and/or burning, and can be quite painful. But, they usually heal without leaving any marks on the skin. And, the anecdotal evidence shows that they clear up within a week or two.
Could COVID Toes Be Linked To Lockdowns?
The research may point to the virus as causing the “COVID toes.” But there are a small pair of studies that indicate the lesions could be the result of lockdowns.
A research team in Belgium reported in the June 25, 2020 issue of JAMA Dermatology that in their study of 31 mostly teenage and young adult patients with purplish-red lesions on their toes and/or fingers, none tested positive for the SARS-CoV-2 virus, which causes COVID. They were also negative for antibodies to the virus.
The researchers concluded that these skin rashes and lesions could be the result of lockdown measures imposed during the pandemic. The majority of participants reported more time spent in sedentary positions and decreased physical activity during the lockdowns when they worked from home or were home-schooled. Another factor was going barefoot or only wearing socks.
What To Do If You Think You Have COVID Toes
Dr. Rodney says that if you think you have COVID toes—but don’t have any other symptoms of the virus—don’t automatically assume you have COVID-19. Those lesions can appear due to other conditions. So, you should get tested for the virus and then talk with your doctor about what to do next.
If it turns out you do have COVID toes, Dr. Zeichner says the rash will last for a week or two. Just keep your feet warm and dry, and wait until the discoloration disappears.