The side effects of the second dose of the COVID-19 vaccine could pack more punch than the first, local health leaders confirmed Friday.
It only happens to about 20% of patients, they said, and it’s not a reason not to get vaccinated, but it’s important to know what to expect when you get the shot.
“We have to be honest and sincere,” said Dr. O’Dell Owens, a longtime physician who now heads the Cincinnati health advocacy group Interact for Health. “The second shot is a little more difficult for you for some people than the first.”
Reported side effects of both the Moderna and Pfizer vaccines, both of which are delivered in two doses at intervals of weeks, include pain, chills, fever and fatigue. A patient may experience all of these side effects from the first injection, but they appear to be stronger after the second injection.
Why? Here’s the short version.
The COVID-19 vaccine is an mRNA vaccine that teaches the recipient’s cells to make a harmless piece of the “spike protein” found on the surface of the virus that causes COVID-19. The vaccine cannot cause a recipient to develop COVID-19, but the presence of the foreign protein still triggers a response from the immune system.
The body produces antibodies that can fight the virus and the patient is protected against illness without ever having to contract the new coronavirus.
The demanding internal process of boosting the immune system and making those antibodies causes most of the side effects of vaccines, not the virus.
What is mRNA?
Good question – it’s also been a few years since we were in high school in biology. mRNA is ‘messenger RNA’, a type of molecule that contains genetic instructions for building a particular type of protein. These instructions are “read” by other cells that make the protein in question. The RNA portion stands for “ribonucleic acid,” a fundamental building block of life. All living things need mRNA to survive.
READ MORE about mRNA vaccines through the Centers for Disease Control and Prevention
Dr. UC Health’s Carl Fichtenbaum compared the immune system to a boxer. Good fighters ferociously protect themselves after a blow, as do bodies that receive more than one dose of a vaccine, even if a two-dose system is needed.
“The response is often a little bit more powerful, more powerful and faster,” he said. “That’s why people often feel a little bit worse when they get the second vaccine than when they get the first vaccine.”
Dr. Phillip Hartman, a St. Elizabeth physician who received his second dose on Wednesday, said he had not experienced any significant side effects.
The percentage of patients who do is about 20% and in some cases, they may not feel well enough to work for a day or two. Hartman said that was expected.
“It’s really minimal discomfort to where you’re going, especially when you consider that I treat patients who had COVID six months ago and are still not breathing properly,” he said.
Owens said he hopes to tell people what to expect, which will keep them calm and knowledgeable about the process, which will make them less vulnerable to scare tactics or conspiracy theories.
“I’m so scared that some people will say, ‘Oh look what happened to me’, and you won’t let these people come back in time for their second shot, and that’s important,” he said.