What is the beta variant? Here’s what we know so far

As the world is busy battling new waves of Covid-19 caused by the highly infectious delta variant, growing concerns in parts of Europe over a strain of ‘beta’ coronavirus first discovered in South Africa. South.

Last week, the UK government announced that anyone traveling to the UK from France should be quarantined even if they were fully vaccinated, because they were concerned about “the continued presence of cases in France of the beta variant” .

France defended its case, noting that most cases of the beta variant are in its overseas territories of Reunion and Mayotte, located in the Indian Ocean, rather than mainland France.

French European Affairs Minister Clément Beaune on Tuesday called the British measures “excessive” and on Monday, French Ambassador to the UK Catherine Colonna cited data showing that cases of the beta variant were down.

There have already been concerns that the Covid vaccines developed over the past year may not be as effective against the beta variant and that they may escape antibody-based drugs.

So is the British government right to be concerned? CNBC has the truth about what we know about the beta variant:

As with all viruses, the coronavirus has mutated several times since its emergence in China in late 2019, although some mutations have been much larger than others, with several having supplanted previous dominant strains.

The alpha variant first discovered in Kent, England, for example, became globally dominant earlier this year before being spoofed by the delta variant which was first detected in India.

Unlike these other “worrisome variants” (according to the World Health Organization), the beta variant appeared around the same time as the alpha but did not take off in the same way, being largely confined to the alpha. ‘South Africa and neighboring countries where it was first detected last fall.

Nevertheless, cases have been detected all over the world. The latest WHO weekly report released on Tuesday showed beta was detected in 130 countries (and seven new countries last week).

The variant, also known as B.1.351, has several important mutations in the virus spike protein – E484K, K417N, and N501Y – that allow this variant to more easily infect people, while potentially making it more difficult to treat, or prevent, with Covid vaccines.

The WHO has said the beta variant is associated with increased transmissibility, increased risk of in-hospital mortality and that there is evidence that it could neutralize antibodies against Covid.

In its latest weekly report, the WHO cited a Canadian study published in July (but not yet peer reviewed) that analyzed data from more than 200,000 cases of Covid-19. He found that compared to non-“variant of concern” strains of Covid, the risks associated with variants containing the N501Y mutation (i.e. alpha, beta, and gamma variants) were significant and carried a risk of hospitalization. much higher, intensive care unit admission and death.

The United States Centers for Disease Control and Prevention (which also classifies beta as a variant of concern and says it is associated with an increased transmission rate of about 50%) noted that laboratory studies suggest that Specific monoclonal antibody treatments might be less effective in treating cases of Covid caused by variants with “certain substitutions or combinations of substitutions in the spike protein”, such as the combination of K417N, E484K and N501Y substitutions present in the beta variant .

The Covid vaccines currently available and primarily used in the West, such as Moderna, Pfizer-BioNTech, and AstraZeneca-Oxford University, are all widely effective in helping prevent severe Covid infection caused by the handful of worrisome variants (including beta) and are proven in studies to reduce hospitalizations and deaths.

However, the WHO noted on Tuesday that with regard to the beta variant, while “protection (is) retained against serious illness”, there is “possible reduced protection against symptomatic illnesses and infections.”

Lawrence Young, virologist and professor of molecular oncology at Warwick Medical School at the University of Warwick in the UK, told CNBC on Wednesday that “we know the delta variant trumps the beta when it comes to transmissibility. , but the beta has been hovering in the background for quite a while. “

“We know he’s more able to resist the vaccine. And all the data we have about it, especially from South Africa, raises concerns about it. [the beta variant] be able to avoid vaccines in a population that is only partially vaccinated or unvaccinated. “

WHO noted that two recent studies in the United States and Qatar had provided further evidence of the strong performance of mRNA vaccines (those from Moderna and Pfizer-BioNTech) against alpha and beta variants.

The first, an American study not yet peer reviewed, found that, tested against all variants, the overall vaccine effectiveness of Moderna or Pfizer-BioNTech vaccines (after two doses) in preventing hospitalization was 86.9 % – although it should be noted that the alpha variant was the most common type (59.7% of viruses sequenced) in the study data.

A second study, from Qatar and published in the journal Nature Medicine on July 9, found that Moderna’s effectiveness against beta variant infection was 61.3% after the first dose and 96.4% after the second dose. The efficacy against any serious, critical or fatal Covid-19 disease due to Covid infection (mainly alpha and beta variants) was 81.6% and 95.7% after the first and second dose, respectively.

The beta variant is even more prevalent in South Africa and neighboring countries, with the increase in cases attributed to the delta variant being much higher. Meanwhile, the United States has sequenced 2,231 cases of the beta variant but none in the past four weeks, according to data from the Gisaid research institute, an initiative to promote global data sharing of Covid-19.

Gisaid’s analysis shows that cases of the beta variant have been found in pockets of Europe, but are still at a relatively low level compared to the highly transmissible delta variant which has become dominant globally.

In the past four weeks, the variant accounted for 3.7% of virus samples sequenced in France (and 6.9% of samples sequenced in Spain), data from Gisaid showed. A very small handful of beta cases (less than 15 in total) have been detected in Portugal, Sweden, Belgium, Germany and the UK in the past four weeks, for comparison.

In South Africa, the mutation accounted for 5.3% of virus samples sequenced. Gisaid noted that the data can be skewed through sampling and reporting bias and however does not represent the exact prevalence of Covid variants.

So, is the UK right to ask arrivals from France to self-quarantine? Young is not convinced, attributing the move more to “panic” than to reason.

“If you look at the current beta infection rates across Europe, Spain has a much higher rate. Recent data suggests that there are over 20% positive cases in Spain while it is about 3.8% in France, “he noted.

“There are a lot of inconsistencies and I dare say ‘knee strike’. I do not see why France has been singled out,” he added.