The Register Citizen (Torrington, CT)
Experts: 2nd dose can cause side effects
The day Dr. Steven Valassis received his second dose of Moderna’s COVID vaccine started out fine.
Valassis, chairman of emergency medicine at St. Vincent’s Medical Center in Bridgeport, received his dose at 10 a.m. and felt fine for much of the day. He knew there were some minor side effects from the vaccine, but his first dose had gone smoothly enough.
However, as the day progressed, Valassis started to feel some aches and fatigue.
“That evening, when I went to sleep, my entire body was sore,” he said. “I felt a bit worn down.”
His response isn’t uncommon. He and other doctors said they’ve heard from others who have had more adverse effects from the second dose than the first shot. Valassis said his experience was relatively minor, as he’s heard of people developing lowgrade fevers and chills after getting the second dose. He’s even heard of some people needing to call out of work.
The Food and Drug
Administration has noted in the “common side effects” section of the emergency use authorization for both the Moderna and Pfizer-BioNTech vaccines that “more people experienced these side effects after the second dose than after the first dose, so it is important for vaccination providers and recipients to expect that there may be some side effects after either dose, but even more so after the second dose.”
But Valassis and colleague, Dr. Daniel Gottschall, said the side effects of the vaccine — even the potentially more intense impact of the second dose — are still better than getting COVID-19.
“It shouldn’t dissuade people, because we know how important this is to preventing the illness, and to preventing people from getting really sick from the illness,” said Gottschall, vice president of medical affairs for the Fairfield region of Hartford HealthCare and St. Vincent’s Medical Center in Bridgeport.
Gottschall said the reason that some people have a more extreme reaction to the second shot is likely just an indicator that the vaccine is working. According to a fact sheet from the state Department of Public Health, the vaccine works by sending instructions to cells in the upper arms to make a harmless protein — known as a “spike protein” — found on the surface of the virus that causes COVID-19.
The immune system recognizes that the protein doesn’t belong in the body, and makes antibodies that signal the immune system to attack. That’s how the vaccine creates antibodies that would usually be created by fighting the virus itself.
However, the immune response involved in creating these antibodies can lead to side effects, such as soreness, fever and fatigue. With the second shot, Gottschall said the effects can be worse because the body is more likely to “recognize” the protein created by the vaccine and “the response can be more vigorous.”
That isn’t the case for everyone. Gottschall said he didn’t experience any major side effects after receiving both doses.
For those who do, the effects usually last only 12 to 24 hours. Valassis said his symptoms were easily treated with Tylenol.
“These symptoms are pretty shortlived,” he said. “When you think about what COVID can do to the body, it’s pretty minimal.”