The United States is now administering 3 million vaccine shots per day. As more people get themselves vaccinated, newer questions arise regarding the second dosage of the vaccines. People have complained that they have suffered side effects after the administration of the second dosage, such as headaches, muscular pains, and fatigue. Many patients who experienced the side effects claimed that they went through “brain fog” or felt like having bad flu.

An app called ‘v-safe’ tracks side effects after the vaccine administration. It has reportedly shown that more side effects are being observed after the second vaccine shot rather than the first one.

As per the data, almost 29% of people reported fatigue after the first shot of the Pfizer-BioNTech vaccine, but the percentage soared to 50% after the second dose. Muscle pain was reported in 17% of people which went to 42% after the second dose and similarly, 7% of people reported experiencing chill and fever after the first dose of vaccine which increased to almost 26% after the second shot.

An analysis of about 13.7 million COVID-19 vaccine shots has concluded that the side effects are more common in women. Almost all the cases of side effects like anaphylaxis or any other allergic reaction occurred in women only.

Another notable notation of the study showed that 1 out of 4 patients did not show any side effects at all beyond having a sore arm.

A member of the Food and Drug Administration’s vaccine advisory panel and a professor at the University of Pennsylvania, Dr. Paul Offit claimed that lack of side effects doesn’t mean that vaccines aren’t working. According to the data collected, people who did not report any side effects were also protected by the coronavirus.

The different reactions to the vaccines show the different ways immune systems tend to respond. According to the data, all three vaccines which are approved to be administered in America – Moderna, Pfizer-BioNTech, and Johnson & Johnson are all qualified against combating the illness.