A US study citing report by the Centers for Disease Control and Prevention (CDC) has stated that most side effects after a booster shot of a Covid-19 vaccine are mild or moderate and occur at about as often as after the second dose. The report was based on a study of more than 22,000 people who signed up to a vaccine safety smartphone app and who received a booster shot between August 12 and September 19.
During this time, third doses were authorised for people who are immunocompromised but not the wider population. "The frequency and type of side effects were similar to those seen after the second vaccine doses, and were mostly mild or moderate and short lived," CDC director Rochelle Walensky said at a press briefing, reports AFP.
Reported side effects include injection site pain (in 71 per cent of the participants), fatigue (56 per cent), and headache (43 per cent). Some 28 per cent reported being unable to perform normal daily activities, usually the next day. Medical care was sought by around two per cent of participants and 0.1 per cent were hospitalized.
A subset of almost 21,700 who received the same mRNA vaccine (Moderna or Pfizer) for all three of their doses was further analyzed. Among those who received Moderna, reaction such as arm pain was reported to be slightly more common after the third dose compared to the second. Systemic reactions which occurred outside the injection site were slightly less frequent after the third dose compared to the second.
The same pattern occurred for Pfizer and in both the cases the first shots resulted in significantly less frequent side effects, compared to shots two and three.
{{/usCountry}}The same pattern occurred for Pfizer and in both the cases the first shots resulted in significantly less frequent side effects, compared to shots two and three.
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