London: A new study published in the journal Lancet Infectious Diseases has confirmed that one in four people experience mild, short-lived systemic side effects like headache, fatigue, and tenderness after receiving either the Pfizer or AstraZeneca vaccine.
Most of the side effects, lasting one to two days, peaked within the first 24 hours following vaccination. They have been majorly found among women under 55 years of age, IANS quoted researchers from the King’s College London as saying.
“The data should reassure many people that in the real world, after-effects of the vaccine are usually mild and short-lived, especially in the over 50s who are most at risk of the infection,” Tim Spector, Professor of Genetic Epidemiology at the varsity was quoted as saying.
“The results also show up to 70 per cent protection after 3 weeks following a single dose,” Spector said.
The team analysed data from 627,383 users of the ZOE Covid Symptom Study app who self-reported systemic and local effects within eight days of receiving one or two doses of the Pfizer vaccine or one dose of the AstraZeneca vaccine between December 8 and March 10, the report added.
New research Article: Vaccine side-effects and #SARSCoV2 infection after vaccination in users of the COVID Symptom Study app in the UK: a prospective observational study https://t.co/UkTsgIRWza, by @timspector and colleagues. #COVID19 @Join_ZOE
— The Lancet Infectious Diseases (@TheLancetInfDis) April 27, 2021
The findings
- 25.4 per cent of vaccinated people indicated suffering from one or more systemic (excluding the area where the injection took place) side effects
- 66.2 per cent reported one or more local (at the injection site) side effects
- About 13.5 per cent of participants reported side effects after their first Pfizer dose
- 22.0 per cent after the second Pfizer dose and 33.7 per cent after the first AstraZeneca dose
The side effects
- Headache: Was the most-reported systemic side effect — 7.8 per cent of people after the first Pfizer dose and 13.2 per cent after the second Pfizer dose, while 22.8 per cent of people reported headache after the first dose of the AstraZeneca vaccine.
- Fatigue: Nearly 8.4 per cent and 14.4 per cent people reported fatigue after the first and second dose of Pfizer vaccine, whileA 21.1 per cent after their first dose of AstraZeneca vaccine.
- Tenderness: A whopping 57.2 per cent and 50.9 per cent reported tenderness after the first and second dose of Pfizer vaccine, and 49.3 per cent after the first dose of AstraZeneca vaccine.
Drop in infection
The study also reports a significant decrease of infection rates from 12 to 21 days after the first dose of the Pfizer (58 per cent reduction) and AstraZeneca (39 per cent reduction) vaccines compared to a control group.
The drop in infection at least 21 days after the first dose for Pfizer is 69 per cent and for AstraZeneca 60 per cent, the findings showed.
COVID survivors were three times more likely to have side effects that affect the whole body after receiving doses of the Pfizer vaccine than those without known infection and almost twice more likely after the first dose of the AstraZeneca vaccine.
