Covid beta variant: here’s what we know

England lifted almost all of its pandemic restrictions on Monday, what some Britons called “freedom day”. The UK government has made one notable exception, however: People traveling to England from France must continue to self-quarantine upon arrival, even if they are fully vaccinated.

The rule, announced on Friday, was spurred on by concerns over the presence of the beta variant of the coronavirus in France and is intended as a precautionary measure, officials said.

“As vaccines help us turn the tide against this virus, we must continue to proceed with caution,” Dr Jenny Harries, chief executive of the UK Health Security Agency, said in a statement on Friday. “This means maintaining our defenses against the new variants and protecting our hard-earned progress through the exceptional rollout of vaccination. “

Here are the answers to some common questions about the beta variant.

What is the beta variant?

The beta variant, formerly known as B.1.351, was first detected in South Africa last year. It contains several mutations, in a protein called a spike, that help the virus bind more tightly to human cells.

It also contains the E484K mutation, sometimes known as the “Eek” mutation, which appears to help the virus partially escape antibodies. This mutation appeared independently in several variants, including Gamma, which surfaced in Brazil, and in some samples of Alpha, which was first identified in Britain.

The World Health Organization and the Centers for Disease Control and Prevention have both named Beta as a “variant of concern.”

Why are people worried about it?

Scientists and health officials worried about the beta as it spread rapidly across South Africa and research indicated that some vaccines were less potent against it.

In February, for example, South Africa stopped using the AstraZeneca-Oxford vaccine after clinical trials suggested the vaccine did not provide good protection against mild or moderate illnesses caused by Beta. (Subsequent research has suggested that several licensed vaccines offer strong protection against serious illnesses caused by the variant.) Britain has relied heavily on the AstraZeneca vaccine, which may explain its caution on beta. .

Some monoclonal antibody treatments are also less effective against the variant, although there are other licensed antibody treatments that appear to work well against it.

The ability of beta to bind tightly to human cells may also make it more transmissible; the CDC notes that it appears to be about 50 percent more infectious than the original strain of the virus. However, he doesn’t appear to be as contagious as Delta.

Where is it common?

Beta has now been reported in 123 countries, but it remains much less common than the Delta.

Initially, Beta spread widely in South Africa, where it once made up over 95% of virus samples sequenced in the country.

He is no longer so dominant. In the past four weeks, Beta has only made up 5.6% of virus samples sequenced in South Africa, according to GISAID, a repository of viral genomes. (This decline is most likely due to the arrival of the highly contagious Delta variant, which now accounts for 77.6% of sequences.)

Over the past four weeks, the variant has also represented 3.7% of virus samples sequenced in France, according to GISAID. It is particularly common in Réunion, a French island in the Indian Ocean where Beta accounts for 31.2 percent of the sequences.

Beta is not common in the United States, where it only accounts for 0.1% of infections, according to CDC estimates. It was detected in Britain, but accounts for a negligible share of infections there.

Do vaccines work against Beta?

The vaccines appear to be less potent against Beta than against other versions of the virus. But studies suggest that two doses of several widely used vaccines should still offer strong protection.

Studies in Qatar, where the beta variant once accounted for half of all infections, found that two doses of Pfizer vaccine are 72 to 75 percent effective in preventing beta infection, a lower level of protection than that. injections against other variants. But the Pfizer and Moderna vaccines both provided strong protection against the worst outcomes; a full cycle of either vaccine was over 95 percent effective in preventing serious illness and death.

“Although Pfizer was only 75% effective against beta, and therefore breakthrough infections with beta are not uncommon, these breakthrough infections are mild and it is very rare for a person to completely vaccinated requires serious hospitalization or dies after a breakthrough beta infection. Laith Abu-Raddad, infectious disease epidemiologist at Weill Cornell Medicine-Qatar who led the two studies, said in an email.

In other good news, he added, there is also “no sign” that the protection these vaccines offer against beta has waned in the first few months after the injections.

In a clinical trial in South Africa, conducted when beta was dominant, the Johnson & Johnson vaccine had an efficacy rate of 64% overall, but an efficacy of 82% in preventing serious disease.