The effectiveness of the Pfizer-BioNTech coronavirus vaccine appears to decline faster than that of the Oxford-AstraZeneca (AZ) jab, according to a new study involving over 350,000 people in the UK, which was published early on Thursday.
The study by researchers of University of Oxford is based on the results of a survey by UK’s Office for National Statistics that carried out RT-PCR tests from December last year to this month on randomly selected households.“Two doses of Pfizer-BioNTech have greater initial effectiveness against new Covid-19 infections, but this declines faster compared with two doses of Oxford-AstraZeneca,” the researchers at Oxford University said. The team is not linked to the group that developed the vaccine. The same vaccine is used as Covishield in India, where it is the mainstay of the inoculation drive.
The study found that “the dynamics of immunity following second doses differed significantly” between Pfizer and AstraZeneca, according to the university’s Nuffield Department of Medicine. Pfizer had “greater initial effectiveness” but saw “faster declines in protection against high viral burden and symptomatic infection”, when looking at a period of several months after full vaccination, although rates remained low for both jabs.“Results suggest that after four to five months, effectiveness of these two vaccines would be similar,” the scientists added, while stressing that long-term effects need to be studied.
– INDIA TODAY