
Temporary side effects like headache, fatigue, and fever are signs the immune system is revving up which are a normal responses to vaccines and are common.
Dr. Peter Marks, the US Food and Drug Administration’s vaccine chief, who experienced fatigue after his first dose said, “The day after getting these vaccines, I wouldn’t plan anything that was strenuous physical activity.”
Here’s what’s happening: The immune system has two main arms, and the first kicks in as soon as the body detects a foreign intruder. White blood cells swarm to the site, prompting inflammation that’s responsible for chills, soreness, fatigue and other side effects.
While this rapid response step of our immune system tends to decrease with age, hence one this is the reason why younger people report side effects more often than the older adults.
Also, some vaccines simply cause more reactions than others. Given that every body reacts differently. Therefore, if somebody didn’t feel anything a day or two after either dose, that doesn’t mean the vaccine isn’t working.
However, behind the scenes, the shots also set in motion the second part of your immune system, and which will provide the real protection from the virus by producing antibodies.
Another nuisance side effect: When the immune system activates, it sometimes causes swelling in lymph nodes for a temporary time period, like those under the arm. Women are encouraged to schedule routine mammograms prior to coronavirus vaccination in order to avoid a swollen node being mistaken for cancer. Though not all side effects are routine.
But among millions of vaccine doses administered around the world are intense and are safety monitored, among which only few have been identified to be serious.
Moreover, a small percentage of people who got vaccines made by AstraZeneca and Johnson & Johnson reported an unusual type of blood clot.
These shots for older adults have been reserved but according to the regulatory authorities the benefits of offering them still overshadow the risks. People also occasionally have serious allergic reactions.
And this is the reason you are asked to stick around for about 15 minutes after getting any type of COVID-19 vaccine in order to ensure any reaction can be promptly treated.
Authorities are finally trying to determine whether temporary heart irritation that can occur with many types of infections also might be a rare side effect after the mRNA vaccines, the kind made by Pfizer and Moderna.
US health officials can’t yet tell if there’s a link but say they’re monitoring a small number of reports, mostly male teens or young adults