A fourth dose of Covid-19 booster vaccine of the Pfizer or Moderna is safe and boosts antibody levels, even higher than that of a third shot, as per the latest results from a countrywide study in the UK.
The researchers said that fourth doses of coronavirus jabs have been offered as a spring booster for those most vulnerable in Britain.
This has been a precautionary strategy to maintain high levels of immunity prior to the study data being available, they added.
The study, published in The Lancet Infectious Disease journal, show that a fourth dose mRNA booster vaccines for the virus are well-tolerated in those who received Pfizer as a third shot.