One dose of COVID-19 vaccine cuts infection rate by 65%; Study shows

By Amirtha P S, Desk Reporter
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COVID-19 Vaccine
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A new UK-based study reveals that a single dose of either the Oxford-AstraZeneca or Pfizer-BioNTech vaccines will reduce the rate of coronavirus infections by around 65 percent.

According to the study jointly conducted by the University of Oxford and the Office of National Statistics (ONS), which are yet to be published, found that a single jab of the two-dose vaccines protected older and more vulnerable people almost as well as younger and healthier individuals.

Even though the findings of the study shows that the vaccination has created a notable decline in the number of hospitalization and death cases from COVID-19 infections, vaccinated people could still be re-infected and trigger an asymptomatic spread of the deadly virus which makes the need for social distancing and face masks still inevitable.

The researchers analyzed COVID-19 test results from more than 350,000 people in the UK between December 2020 and April 2021 and found that 21 days after a first jab, the time it takes the immune system to build a decent response, new COVID-19 infections dropped.

“Odds of new SARS-COV-2 infection were reduced 65 percent in those 21 days since the first vaccination with no second dose versus unvaccinated individuals without evidence of prior infection. In those vaccinated, the largest reduction in odds was seen post-second dose (70-77 percent). There was no evidence that these benefits varied between Oxford-AstraZeneca and Pfizer-BioNTech vaccines,” study shows.

In the large community surveillance study, the researchers found that vaccination with a single dose of Oxford-AstraZeneca or Pfizer-BioNTech vaccines, or two doses of Pfizer-BioNTech, significantly reduced new SARS-COV-2 infections.

The second study conducted in nearly 46,000 adults who had been vaccinated with one dose, found strong antibody responses in all age groups. These antibody responses were “broadly sustained out to 10 weeks afterward”, the researchers said.

“We don’t yet know exactly how much of an antibody response, and for how long, is needed to protect people against getting COVID-19 in the long term but over the next year, information from the survey should help us to answer these questions,” said Professor Sarah Walker, chief investigator on the studies, from Oxford University.

Earlier this week, the National Health Service (NHS) said its vaccination program has now protected around 28 million people in England with at least one jab and delivered more than 9 million second doses.

Related: ‘Pandemic can be brought under control within months:’ WHO Chief