(Bloomberg) -- England is gearing up for its fourth winter with Covid-19 by pulling forward its vaccination booster program by a month after the emergence of a new variant, dubbed Pirola. While little is known about this latest strain of a virus that is constantly mutating, the UK Health Security Agency decided to move its schedule forward preemptively to protect the most vulnerable from illness. The US Centers for Disease Control and Prevention and the World Health Organization have already said they are keeping a close eye on the situation.

Why is the UK changing its booster schedule?

The prevalence of Pirola, officially known as BA.2.86, is still low but the variant is proving more adept at evading immunity from vaccines and past infections. That’s due to a large number of mutations on its spike protein, which helps the virus latch onto cells and cause infections. As immunity to Covid, either from earlier shots or actual infection, wanes over time it’s important to top up vaccinations. The earlier it’s done, the better the chance of avoiding a new wave of Covid infections. 

Is the new variant dangerous?

It’s too early to say. There’s no public data yet showing that BA.2.86 can overwhelm current immunity levels but England is heading into winter when people spend more time indoors which can aid the spread of a virus. “The mutations present in BA.2.86 mean that there are a lot of unanswered questions surrounding how it will behave come the winter when there is increased risk of Covid-19 making people seriously ill,” said Simon Clarke, associate professor in cellular microbiology at the University of Reading. 

What symptoms does BA.2.86 cause?

The symptoms of Pirola seem to be the same as those caused by previous strains, according to Thomas Russo, chief of the Division of Infectious Diseases at the University of Buffalo’s medical school. Common ones include a runny nose, sneezing, headache, a sore throat and fatigue. People who are older, have compromised immune systems or suffer from multiple other conditions are at higher risk for more severe effects. These may include lower respiratory disease, chest pain and shortness of breath.

Who can get a Covid booster this fall in the UK?

People in care homes, the clinically vulnerable, those age 65 and over, and health and social care workers will be able to get a Covid shot starting from Sept. 11. Britons can pair the booster with a flu shot where possible, as it’s easier to get one in each arm in the same visit.

Is there an adapted vaccine booster for Pirola?

Drug makers have been adapting Covid vaccines to better protect against circulating variants, but not as fast as the virus itself. The current vaccines available in the UK are not designed specifically to protect against Pirola. That said, a booster still helps reduce the risk, especially in the first three months after vaccination, because immunity to new variants tends to be better with higher levels of circulating antibodies, according to Claire Steves, professor of aging and health at King’s College London. 

Will there be another lockdown in the UK this winter?

At this point, it seems unlikely. Most Britons don’t support another national lockdown, according to a 2022 opinion poll, and small businesses and the hospitality sector were particularly badly hit by previous closures. Former UK prime minister Boris Johnson said in September 2021 that Britain has to learn to live with the virus, and lockdowns have become a measure of last resort.

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