Written By: Longjam Dineshwori | Updated : December 11, 2021 3:10 PM IST
Omicron scare spurs calls for booster doses against Covid-19
Studies are underway around the world to understand the impact of the fast-spreading Omicron SARS-CoV-2 variant on current vaccine effectiveness. Preliminary results suggest that the new variant is highly likely to compromise some of the protection conferred by existing COVID-19 vaccines and that booster shots may be needed to improve immunity against it.
Based on the findings of a new study, the UK Health Security Agency (UKHSA) also stated two doses of a Covid-19 vaccine may not be enough against the Omicron variant, and a third dose is necessary to prevent the super mutant variant. It
The study found lower vaccine effectiveness against symptomatic Omicron infection compared to the original strain of Covid-19 or the Delta variant after a full two-dose vaccination course. However, a moderate to high vaccine effectiveness of 70 to 75 per cent is seen after a booster dose, the agency said in a statement.
Laboratory studies by researchers in South Africa, Germany and Sweden also indicate that protection conferred by existing COVID-19 vaccines may not be enough to fight Omicron and that boosters should be introduced.
To calculate how effective the current vaccines were against the Omicron variant, the UK study analysed data from 581 Omicron cases and thousands of Delta cases. The analysis showed a significant drop in effectiveness for the Oxford-AstraZeneca and Pfizer vaccines, the UKHSA said, adding that other vaccines are likely to have similar results.
Further, the agency noted that the 75 per cent protection against Covid symptoms after a booster is less than previous variants.
Dr Mary Ramsay, head of immunisation at the UKHSA, stated that there is a greater risk of catching the Omicron variant a few months after the second vaccine jab.
But two shots of a Covid vaccine are expected to provide higher protection against serious complications of Covid-19. So, she asked people who haven't yet had their first two doses to book an appointment straight away.
As reported by the BBC, 448 more cases of Omicron have been confirmed in the UK, taking the total number so far to 1,265.
By mid-December, the UKHSA estimates that more than half of all cases in the country will be Omicron. If growth continues unabated, more than 100,000 cases a day are expected by the end of the month.
With inputs from agencies
