LONDON — The rise of the Covid-19 delta variant in the U.K. has sparked fears of a new wave of the virus and could endanger plans for a full reopening of society this month, despite one of the world's most successful vaccination campaigns.
Recorded cases are nearing levels reached in March this year, with 4,000 to 6,000 cases a day over the last 10 days. The delta variant, first identified in India, is more contagious, spreads more rapidly and is now the dominant strain of the virus in the U.K.
“We are a country with a vaccine-only strategy, and we’ve imported a variant that is more transmissible and more likely to escape,” said Deepti Gurdasani, a clinical epidemiologist and senior lecturer at Queen Mary University of London, who criticized the absence of other infection control measures, such as masks in schools.
After a strict lockdown throughout the winter, the government began slowly lifting coronavirus restrictions in March. June 21 was set to be the last target date for the final lifting of all restrictions, when nightclubs and other large-scale events would reopen.
However, senior politicians have warned that the government is carefully watching the increasing number of cases and that date could be missed. British newspapers have started to refer to June 21 as "freedom day" and are amplifying calls from some lawmakers to make sure that's when all restrictions end.
“These are difficult judgments based on uncertain data,” Health Secretary Matt Hancock told Parliament on Tuesday.
“We face a challenging decision ahead of the June 21, but that decision is made easier, and made possible because of the U.K. vaccination program.”
Delaying the date for the full reopening of society would give more people time to get a second vaccination. Around three-quarters of Britain's adult population has received at least one dose of a coronavirus vaccine, and more than 40 percent have received two doses.
At the moment, vaccines are available to anyone over the age of 25 in England and over the age of 30 in Scotland. The government has said that two doses of a vaccine are more likely to prevent infection with the new variant in particular and it is encouraging people to come forward for their second dose if they are due and haven’t received it yet.
As of Tuesday, there were 879 people in hospitals in England for Covid-19 treatment, slightly higher than the low of 730 last month.
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While experts in Britain are not worried about a wave as deadly as the one that swept the country in December and January, they do fear a continued rise in infections, especially among young people who have yet to receive a vaccine.
“There is an argument that cases among young people matter less, but we do know that a sizable number of cases will lead to hospitalization,” said Oliver Johnson, a professor of information theory at the University of Bristol, who monitors Covid-19 data in the U.K. “My worry is that a wave of cases does lead to a proportionate wave of hospitalizations as well.”
Britain's overall death toll from the pandemic stands at 128,118, one of the highest in the world, according to Johns Hopkins University data.
Other experts like Gurdasani fear that without an effort to lower cases to near zero, future variants will continue to endanger an overall lifting of restrictions.
“We do need to contain the pandemic if we want to return to normal life, because unless we do that we will be stuck in this for years,” she said. “We need to pivot from living with virus to eliminating virus alongside vaccine rollout.”
The U.K. government isn’t alone in its renewed push for people to get two doses of the vaccine.
President Joe Biden warned of the variant’s spread in the U.K. and encouraged young people to get vaccinated in a tweet on Tuesday evening.
“If you’re young and haven’t gotten your shot yet, it really is time. It’s the best way to protect yourself and those you love,” he wrote.
Scientists in the U.K. expect that, even with precautions, the delta variant will continue to spread both locally and around the world.
"I think other countries will go down a similar path, and I suspect it will spread globally over time," said Jeff Barrett, director of the Covid-19 Genomics Initiative at the Wellcome Sanger Institute, at a news briefing Wednesday.
"If you look at the U.S. data, it is starting to go up, and I think the U.S. will be the next place we will see a reasonable rise."
In the U.S., the delta variant currently accounts for more than 6 percent of sequenced cases, Dr. Anthony Fauci, the director of the National Institute of Allergy and Infectious Diseases, said at a news briefing Tuesday.
Speaking of the way the delta variant had become dominant in the U.K., Fauci said: "We cannot let that happen in the United States, which is such a powerful argument ... to get vaccinated. Particularly if you had your first dose, make sure you get that second dose."