TORONTO -- The Canadian Paediatric Surveillance Program (CPSP) is warning doctors and parents about skin changes on children's feet or hands as a possible sign of COVID-19 infection.

A public health alert issued to pediatricians identifies the bluish-red and purple lesions -- dubbed "COVID toes" -- found on the toes and fingers as a possible symptom of COVID-19 infection, predominantly found in children.

Pediatric emergency physician Dr. Dina Kulik told CTV News Channel that the lesions look similar to pernio, commonly referred to as frostbite, and can hurt or feel warm when touched.

"COVID toes is a skin finding that we are seeing in some children, but also some adults that are diagnosed with COVID. Even people that haven't been diagnosed, we're seeing it more and more," Kulik said in an interview on Monday. "It looks like frostbite [with] red or purple or brown discolouration around the feet, could be on the underside of the foot, the top of the foot, on the toes, and sometimes there's cracked or dry looking skin as well."

While this evidence is not yet backed by peer-reviewed studies, the alert states that children may be otherwise asymptomatic or have mild symptoms in addition to the skin lesions.

"Some children will have just this rash, some kids will have the rash accompanied by other COVID symptoms like runny nose, cough or fever or belly aches, vomiting or diarrhea," Kulik said.

The CPSP says the lesions should prompt clinicians to test for the novel coronavirus. Researchers say the testing is necessary to ensure proper tracking of potential community spread and to initiate self-isolation for patients and anyone who may have come into contact with them.

"[COVID toes] seems to be reported more and more in the setting of COVID and more frequently in the last couple of months," Kulik said. "It doesn't look like really any other diagnosable illness in children. There are many rashes that come with certain viral infections [in] kids, but this doesn't look like hand-foot-and-mouth disease or roseola or other viral infections that lead to rashes in children."

CTV medical contributor Dr. Marla Shapiro told CTV News Channel that the skin lesions may be caused by small blood clots forming in veins not normally affected by critical illnesses.

"It's very possible, because of the heightened immune state that is present in COVID in children who don’t really have any of the respiratory symptoms, that what you're seeing is a vasculitis or inflammation of these very small blood vessels that are typically at the ends of toes and the ends of fingers," Shapiro said on Tuesday. "[It's] almost as if you have these little, mini clots in them due to the inflammation and that's giving you the purple-bluish lesions."

Doctors say some COVID-19 patients are developing fast-moving, potentially life-threatening blood clots, leading to stroke and limb amputation. However, Shapiro says the blood vessels in the toes and fingers are likely too small to create serious the clotting problems that could occur elsewhere in the body.

Kulik said, like COVID-19, there is no treatment for the skin lesions.

"We watch and we wait. We don't typically do anything. Like most other viral rashes they resolve on their own. Certainly if the person is feeling discomfort to take a pain medicine could be helpful or using topical medicine like hydrocortisone to decrease the inflammation or the itch if they're bothering the person," she said.

Doctors are asked to report all confirmed cases of COVID-19 in a child with skin lesions to the CPSP.

Initial reports about skin problems associated with COVID-19 were first documented in late March by a doctor in Italy who found that 18 of the 88 patients studied (20 per cent) had some kind of skin problem.

In response, the American Academy of Dermatology has asked its members and other physicians around the world to report any dermatological symptoms associated with COVID-19 to a registry so doctors can better understand how COVID-19 affects the skin.

A podiatrists' association in Spain has also opened a registry to track skin conditions that may be related to the virus. France's National Union of Dermatologists also issued a notice to its members that the lesions can be a possible sign of infection.

The World Health Organization (WHO) does not list skin problems as known symptoms of COVID-19, but has been watching closely as experts in several countries continue to study the issue.

Kulik said parents should call their family doctor if they notice any skin problems in themselves or their children.

"If your child is unwell, of course you want to seek medical care, if your child is very unwell you'll want to go to the emergency room. But if, just a rash and no other symptoms, it's best to touch base with your physician and stay home, stay isolated, and make sure you're not seeing anyone that's at risk of serious infection like the elderly and people with chronic health conditions," Kulik said.