Spread of COVID-19 variant forces U.K. to reduce interval of second vaccine doses to older Britons

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The British government has been forced to adjust the rollout of its vaccination program as the country faces a surge in COVID-19 variants first detected in India, which has dealt a setback to efforts to control the pandemic.

The number of cases of a mutation known as B.1.617.2 has nearly doubled in the past couple of weeks to 1,313, according to figures from Public Health England. Most of the infections have been clustered around Manchester, Glasgow and London, but health experts believe the variant has likely spread much farther. Cases involving a similar version of the variant, known as B.1.617, have also climbed to 368, up by 107 since May 5. So far four people have died from the variants.

“We believe this variant is more transmissible ... but we don’t know by how much,” Prime Minister Boris Johnson said during a televised news conference Friday. “If the variant is significantly more transmissible, we’re likely to face some hard choices.”

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Mr. Johnson said the government will reduce the interval between the first and second doses of vaccines to eight weeks from 12 for people aged 50 and over, in order to ensure that vulnerable populations have greater protection against the variant. Health officials are also considering sending more vaccine doses to areas of the country that have been hardest hit by the mutations to increase the pace of vaccination. So far slightly more than two-thirds of U.K. adults have had one shot of a COVID-19 vaccine; 19.3 million people, more than 30 per cent, have had two.

David Greenhalgh, the leader of Bolton Council, a suburb of Greater Manchester, said the vast majority of cases of the variant in his community involved teenagers and people in their 20s and 30s, age groups that have yet to be immunized. He has called for a surge of vaccinations for younger people in Bolton. “If we can get vaccinations to [people aged] 16 plus, which are licensed by Pfizer, then it will make a total transformation of the transmission as it moves forward,” Mr. Greenhalgh told the BBC on Friday.

But diverting doses away from the national program could leave other regions vulnerable and disrupt the overall vaccination campaign, health officials argued. It also takes a couple of weeks for vaccines to take effect, which would offer little benefit for the current outbreak. “We have a finite supply at any given moment of vaccine,” Chris Whitty, the government’s Chief Medical Officer said during the news conference. “So if you vaccinate one person, by definition you’re not vaccinating another. … This would lead to a net disadvantage overall.” Instead, Dr. Whitty said accelerating second doses across the country was a better option.

Mr. Johnson is now under pressure to delay the government’s plans to open up much of the economy on Monday and remove nearly all lockdown restrictions next month. As of Monday, pubs and restaurants across England will be able to offer indoor service and many other venues will also be allowed to reopen including movie theatres, museums and sport stadiums, which will have a limited number of spectators. Domestic travel restrictions will also be eased, allowing people greater freedom to move around the country and stay overnight.

Similar steps were set to be taken in Scotland, Wales and Northern Ireland, but on Friday Scotland’s First Minister Nicola Sturgeon said current lockdown measures will remain in place in Glasgow and the Moray region where the number of variant cases have increased.

Mr. Johnson said that the number of deaths and hospitalizations caused by COVID-19 continue to fall, even in Bolton and other hot spots. He also said there was no evidence that the current vaccines will be less effective against the variants.

“I do not believe that we need, on the present evidence, to delay our road map and we will proceed with our plan to move to step three in England from Monday,” he said. “But I have to level with you that this new variant could pose a serious disruption to our progress and could make it more difficult to move to step four in June.” He also urged people to think twice about travelling to Bolton and other areas of the country where the variants were prevalent.

The government’s Scientific Advisory Group for Emergencies said Friday that the variant could be as much as 50-per-cent more transmissible than the B.1.1.7 mutation, which has dominated Britain for months. “We expect over time, this variant [B.1.617.2] to overtake and come to dominate in the U.K. in the way that B.1.1.7 took over and indeed other variants have taken over prior to that,” Dr. Whitty said. He added that if the variant proved to be much more transmissible, “we could have a really significant surge.”

On an overall basis, the number of daily COVID-19 infections across Britain has remained low for weeks at around 2,500. Deaths have fallen even sharper since January along with hospitalizations, which are at the lowest level since last summer. “The vaccine deployment program remains successful,” Dr. Whitty said. “Vaccines are reducing hospitalizations and deaths – there is very clear evidence they are and nothing has changed on that.”

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