What’s the beta model? We all know that up to now

People enjoy the sun and warm weather on Segur de Calafell beach in Spain, where beta falls are increasing.

SOPA pictures | LightRakete | Getty Images

While the world is busy fighting more Covid-19 waves through the highly contagious Delta variant, concerns about the beta variant discovered in South Africa are growing in parts of Europe.

Last week the UK government announced that anyone traveling to the UK from France will need to be quarantined even if they are fully vaccinated as they are concerned about “the persistent presence of beta cases in France” .

France has defended its case file, finding that most of the beta variant cases occur in its overseas territories of La Réunion and Mayotte, which are in the Indian Ocean, rather than mainland France.

On Tuesday, France’s European Minister Clement Beaune described the British measures as “excessive” and on Monday, France’s ambassador to the UK, Catherine Colonna, cited data showing that beta cases are on the decline.

Previously, there were concerns that Covid vaccines developed last year may not be as effective against the beta variant and bypass antibody drugs.

So is the UK government right to be concerned? CNBC has the facts about what we know about the beta variant.

What is the beta version?

As with all viruses, the coronavirus has mutated multiple times since it appeared in China in late 2019, although some mutations were far more significant than others, with several earlier dominant strains supplanting.

The alpha variant, first discovered in Kent, England, for example, became dominant worldwide earlier this year before it was usurped by the delta variant, first discovered in India.

Unlike these other “worrying variants”, the beta variant emerged around the same time as Alpha, but did not start in the same way as it was largely confined to South Africa and the surrounding countries where it was discovered last fall.

However, cases have been found worldwide. The World Health Organization’s latest weekly report on Tuesday showed that beta was discovered in 130 countries and seven new countries in the past week.

Why is it worrisome?

The variant, also known as B.1.351, has several significant mutations in the virus’ spike protein – E484K, K417N, and N501Y – that make it easier for this variant to infect people and possibly more difficult to treat, or with Covid vaccines to prevent.

The WHO has stated that the beta variant is linked to increased transmissibility, a possible increased risk of death in the hospital 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 peer-reviewed that analyzed data from over 200,000 Covid-19 cases. It found that when compared to non-worrying strains of Covid, the risks associated with variants with the N501Y mutation (i.e. the alpha, beta, and gamma variants) were significant and a much higher risk of hospitalization, admission the intensive care unit and death.

The US Centers for Disease Control and Prevention also classify beta as a worrying variant, saying it is linked to an approximately 50% increase in transmission rate. The CDC has said that laboratory studies suggest that specific monoclonal antibody treatments may be less effective in treating cases of Covid caused by variants with “certain substitutions or combinations of substitutions in the spike protein”. They include the combination of K417N, E484K, and N501Y substitutions seen in the beta variant.

Do vaccines work against this?

The Covid vaccines currently available and predominantly used in the west, such as Moderna, Pfizer-BioNTech, and AstraZeneca-Oxford University, are all largely effective in preventing severe Covid infection caused by a handful of worrying variants, including Beta Proven in studies to reduce hospital stays and deaths.

However, the WHO stated on Tuesday that although the beta variant “maintains protection against severe illnesses”, there is “possibly reduced protection against symptomatic illnesses and infections”.

Lawrence Young, virologist and professor of molecular oncology at the University of Warwick’s Warwick Medical School, told CNBC on Wednesday that “we know the delta variant outperforms beta in terms of portability, but beta has been floating in the air for years Background for a while. “

“We know it can withstand the vaccine better. And all the data we have on it, especially from South Africa, is cause for concern.” [the beta variant] to be able to avoid vaccines in a population that is only partially vaccinated or not vaccinated. “

WHO noted that two recent studies in the US and Qatar had provided further evidence of the solid performance of mRNA vaccines – those from Moderna and Pfizer-BioNTech – against the alpha and beta variants.

The first, a US study that has not yet been peer-reviewed, found that the overall vaccine effectiveness of the Moderna or Pfizer BioNTech vaccines after two doses in preventing hospitalization was 86.9% for all variants – though Note that the alpha variant was the most common type, 59.7% of the viruses sequenced, in the study data.

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

Where is it?

The beta variant is even more common in South Africa and neighboring countries, with the increase in cases of the delta variant being much higher. According to the research institute Gisaid, an initiative that promotes the exchange of global Covid-19 data, the US has now sequenced 2,231 cases of the beta variant, but none in the last four weeks.

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

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), Gisaid data showed. For comparison, a very small handful of beta cases (less than 15 total) have been detected in Portugal, Sweden, Belgium, Germany and the United Kingdom over the past four weeks.

WHO map showing the global prevalence of variants

World health organization

In South Africa, the mutation accounted for 5.3% of the virus samples sequenced. Gisaid noted that the data can be skewed by sample and report bias, but does not reflect the exact prevalence of Covid variants.

So is it right for Britain to quarantine newcomers from France? Young is not convinced and attributes the move to “panic” rather than 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 in France it is around 3.8%, ”he noted.

“There are a lot of inconsistencies and I dare say ‘knee-jerk’. I don’t understand why France was chosen that way,” he added.

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