Delayed skin reactions appear after vaccines

Some people have late reactions to their first dose of a Covid vaccine, with their arms becoming red, sore, itchy, and swollen about a week after the injection.

The reactions, while unpleasant, seem harmless. But the condition of the skin that appears angry can be mistaken for an infection, according to a letter published Wednesday in the New England Journal of Medicine. Doctors said they want to share case information to help prevent unnecessary antibiotic use and to allay patients’ concerns and reassure them that it is safe to get their second vaccine.

“We changed our patient record once we started to see this,” said Dr. Kimberly G. Blumenthal, letter author and allergist at Massachusetts General Hospital, in an interview. “We said it was normal to have redness, itching and swelling when you get the vaccine. We’ve changed the wording to say that it can also start seven to ten days after you get the vaccine. “

The letter describes the experiences of 12 people who had “delayed significant local reactions” that began four to 11 days after the first Moderna vaccine, within a median of eight days. The report is not a controlled study, but rather a series of cases that caught the attention of doctors because those vaccinated were worried and wanted to know if they should be vaccinated.

Most were vaccinated at Massachusetts General Hospital, where Moderna and Pfizer-BioNTech vaccines were administered. But the late reactions only occurred in people who had received the Moderna vaccine, Dr Blumenthal said, adding: “I don’t understand why.”

Moderna reported delayed skin reactions in its large clinical trial in 0.8% of recipients after the first dose and 0.2% after the second dose.

According to the letter from Dr Blumenthal and 10 other doctors, all 12 people reported typical symptoms like arm pain that often occurs soon after inoculation, and those early symptoms went away.

Then a delayed reaction struck. In five people, large raised skin lesions appeared, measuring at least 10 centimeters in diameter near the injection site. Two had rashes in other places, one near the elbow and one on the palm of their hands. Some also had systemic symptoms at the same time, such as fatigue and muscle pain.

Most treated the skin symptoms with ice and antihistamines. But some needed steroids, in cream or pill form, and one was prescribed an antibiotic by a doctor who mistook the problem for an infection.

Symptoms lasted an average of six days, ranging from two to 11 days. All patients then received the second vaccine. Half did not have another delayed reaction, but three again developed the same symptoms and three had milder reactions than after the first stroke.

Dr Blumenthal said there were many unanswered questions about the reactions. Ten of the 12 patients were women, but it is not clear whether women are more prone to the problem or whether the imbalance occurred because more of the health workers vaccinated were women.

Some had allergies to drugs, wasp stings, or food, but others did not.

A skin biopsy on one patient indicated the condition to be a drug reaction. But what exactly the patient’s immune system reacted to is not known.

“I hope companies will understand this,” said Dr Blumenthal.

She is aware of around 30 cases currently, mostly among women and all Moderna vaccine recipients so far, she said, and the hospital has created a registry to track them.