Beta Variant of Covid: Here’s What We Know


England removed almost all Some Britons on Monday from pandemic restrictions hailed as “freedom day”” But the British government made a notable exception: people traveling from France to England quarantine should continue even if they are fully vaccinated when they arrive.

Officials said the rule, announced on Friday, stemmed from concerns over the existence of a Beta variant of the coronavirus in France and was designed as a precautionary measure.

CEO of the UK Health Security Agency, Dr. “While vaccines help us change the situation against this virus, we need to continue to move forward with caution,” said Jenny Harries. said in a statement on Friday. “This means maintaining our defense against new variants and preserving our hard-won progress through exceptional vaccine delivery.”

Find answers to some frequently asked questions about the beta variant here.

Beta variant, formerly known as B.1.351 first detected Last year in South Africa. This includes a few mutationsIt is found in a protein called spike that helps the virus attach more tightly to human cells.

It also includes the E484K mutation, sometimes known as the “Eek” mutation, which appears to help the virus partially evade antibodies. This mutation arose independently in several variants, including Gamma, which originated in Brazil and in some alpha sampleswas first described in England.

The World Health Organization and the Centers for Disease Control and Prevention have identified Beta as “an alarming variable.”

Scientists and health officials worried about Beta because it spread rapidly in South Africa, and research has shown that some vaccines are less potent against it.

For example, in February, South Africa stopped using The AstraZeneca-Oxford vaccine has suggested, after clinical trials, that the vaccine does not protect well against mild or moderate disease caused by Beta. (Further research has suggested that several authorized vaccines offer strong protection against serious diseases caused by the variant.)

Some monoclonal antibody treatments also less effective against the variant, although there are other authoritative antibody treatments seems to be working fine against it.

Beta’s ability to bind tightly to human cells may also make it more contagious; CDC notes The virus appears to be roughly 50 percent more contagious than the original strain. But it doesn’t seem as contagious as Delta.

Beta currently reported: 123 countries, but remains much less common than Delta.

Initially, Beta spread widely in South Africa and was once 95 percent of virus samples ranked in the country.

It’s not that dominant anymore. In the past four weeks, Beta has made up just 5.6 percent of the virus samples sequenced in South Africa. according to GISAIDa repository of viral genomes. (This decline is most likely due to the arrival of the highly contagious Delta variant, which currently accounts for 77.6 percent of sequences.)

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

Beta not common In the United States, where it represents only 0.1 percent of infections, according to CDC estimates. It has been detected in the UK, but there is a negligible share of infections there.

Vaccines appear to be less potent against Beta than against other versions of the virus. But research shows that two doses of several commonly used vaccines should still provide strong protection.

Studies in Qatar, where the beta variant once accounted for half of all infections, found two doses of Pfizer vaccine are 72 to 75 percent effective in preventing Beta infection; this is a lower degree of protection than vaccines provide against other variants. But both Pfizer and Moderna vaccines provided strong protection against the worst consequences; A full course of both vaccines was more than 95 percent effective in preventing serious illness and death.

“Although Pfizer’s efficacy against Beta is only 75 percent, and so breakthrough infections with Beta are not uncommon, these breakthrough infections are mild, and it’s very rare for someone fully vaccinated to require serious hospitalization or die after a Beta new infection.” Laith Abu-Raddad, an infectious disease epidemiologist at Weill Cornell Medicine-Qatar who led both studies, said in an email.

As additional good news, he added, there is no “sign” that the protection these vaccines offer against Beta diminishes in the first few months after vaccinations.

Johnson & Johnson vaccine in a clinical trial conducted during Beta-dominant times in South Africa had an activity rate 64 percent overall, but 82 percent effectiveness in preventing serious disease.


Source link

Leave a Reply

Your email address will not be published. Required fields are marked *