Infectious-disease specialists are working to reassure people that they are still getting protection from Covid-19 vaccines, even if they don’t experience the flulike side effects that hit some people after vaccination.
Fatigue, chills and other symptoms in the days following vaccination are evidence that the vaccine is having the desired effect on the body’s immune system, according to public health officials. The U.S. Centers for Disease Control and Prevention and the World Health Organization say on their websites that side effects mean the body is “building protection” against the coronavirus.
That message may lead some people to infer that the absence of side effects indicates that vaccination isn’t causing the body to build immunity to the virus. Yet infectious-disease doctors say most people get protection from the vaccines, even if they don’t experience side effects.
“I don’t think someone should correlate the extent of their reactions to the vaccine with protection from infection,” said H. Cody Meissner, chief of the pediatric infectious diseases division at Tufts University School of Medicine in Boston. “We know that people who don’t respond to a vaccine in terms of the side effects still are well protected. The vaccines work even if you don’t have fatigue and headache and fever and muscle pain and joint pain.”
Experts say more research is needed to establish what vaccine-related side effects, or their absence, tell us about the strength of people’s immune responses. “There are just so many nuances in terms of how you respond,” said Kathryn Edwards, professor of pediatrics and a vaccine researcher at Vanderbilt University School of Medicine in Nashville, Tenn.