Single COVID vaccine dose boosts protection against variants in previously infected: Study
NEW DELHI :
A SINGLE dose of COVID-19 vaccine boosts protection against SARS-CoV-2 coronavirus variants, but only in those previously infected with the disease, according to a study. The researchers looked at the UK and South Africa variants, however, they think it possible that the findings will apply to other variants in circulation, such as the Brazil (P.1) and India (B.1.617 and B.1.618) variants.
The findings, published in the journal Science, show that in those who have not previously been infected and have so far only received one dose of vaccine, the immune response to coronavirus variants of concern may be insufficient. The researchers at Imperial College London, Queen Mary University of London and University College London, looked at immune responses in UK healthcare workers at Barts and Royal Free hospitals following their first dose of the Pfizer/BioNTech vaccine.
They found that people who had previously had mild or asymptomatic infection had significantly enhanced protection against the Kent and South Africa variants, after a single dose of the mRNA vaccine. In those without prior COVID-19, the immune response was less strong after a first dose, potentially leaving them at risk from variants. “Our findings show that people who have had their first dose of vaccine, and who have not previously been infected with SARS-CoV-2, are not fully protected against the circulating variants of concern,” said Rosemary Boyton, Professor of Immunology and Respiratory Medicine at Imperial College London, who led the research. “This study highlights the importance of getting second doses of the vaccine rolled out to protect the population,” Boyton said.