1 in 4 people face side effects after getting COVID-19 vaccine

One in four people experiences side effects after being vaccinated against coronavirus. These are mostly minor side effects like pain at the injection site or headache, Lancet Infectious Diseases reported.

Analysis of data from the ZOE COVID Symptom Study, conducted by researchers at King's College London, found that side effects in the general population after vaccination with Pfizer and AstraZeneca were much lower than those reported in the trials.

The study also reported a significant reduction in infection rates from 12 to 21 days after the first dose of Pfizer (58% reduction) and AstraZeneca (39% reduction) compared to controls. The reduction in infection at least 21 days after the first dose is 69% for Pfizer and 60% for AstraZeneca.

Research has shown that:

• 25.4% of vaccinated people reported one or more systemic side effects, while 66.2% reported one or more local side effects.
• 13.5% of participants reported side effects after the first dose of Pfizer, 22.0% after the second dose of Pfizer, and 33.7% after the first dose of AstraZeneca.
• The most common systemic side effect was a headache. 7.8% of people reported headaches after the first dose of Pfizer and 13.2% after the second dose of Pfizer. 22.8% of people who received the first dose of the AstraZeneca vaccine reported headaches.
• The second most common systemic side effect was fatigue. 8.4% and 14.4% of participants reported fatigue after the first and second doses of the Pfizer vaccine, and 21.1% reported fatigue after the first dose of the AstraZeneca vaccine.
• The most common localized side effect was soreness: 57.2% and 50.9% after the first and second doses of Pfizer vaccine and 49.3% after the first dose of AstraZeneca vaccine.

Side effects were more common in people under the age of 55 and in women.