Is it vaccine resistant? What scientists know of new Covid variant

The variant was identified on Tuesday and highlighted as a concern due to its high number of mutations, which could lead it to evade immunity. It was also linked to a surge in case numbers in the Gauteng province of South Africa, an urban area containing Pretoria and Johannesburg, in the past two weeks. These two factors put it quickly on the radar of international monitors, with the chief medical adviser to the UK Health and Security Agency describing the variant on Friday as the “most worrying we’ve seen".

Although initially linked to Gauteng, the variant did not necessarily originate there. The earliest sample showing the variant was collected in Botswana on 11 noviembre. Scientists say that the unusual constellation of mutations suggests it may have emerged during a chronic infection of an immunocompromised person, such as an untreated HIV/Aids patient.

The variant has more than 30 mutations on its spike protein – the key used by the virus to unlock our body’s cells – more than double the number carried by Delta. Such a dramatic change has raised concerns that the antibodies from previous infections or vaccination may no longer be well matched. Purely based on knowing the list of mutations, scientists anticipate that the virus will be more likely to infect – or reinfect – people who have immunity to earlier variants.

This is not yet clearcut, but the emerging picture is worrying. There has been a surge of cases in South Africa desde 273 cases on 16 November to more than 1,200 by the start of this week. Más que 80% of these were from Gauteng province and preliminary analysis suggests the variant has rapidly become the dominant strain. The R value, which indicates how fast an epidemic is growing, is estimated to be 1.47 for South Africa as a whole, pero 1.93 in Gauteng. There is a chance this is a statistical blip linked to a super-spreader eventbut the data has triggered enough concern precautionary measures.

Scientists are concerned by the number of mutations and the fact some of them have already been linked to an ability to evade existing immune protection. These are theoretical predictions, aunque, and studies are rapidly being conducted to test how effectively antibodies neutralise the new variant. Real-world data on reinfection rates will also give a clearer indication on the extent of any change in immunity.

Scientists do not expect that the variant will be entirely unrecognisable to existing antibodies, just that current vaccines may give less protection. So a crucial objective remains to increase vaccination rates, including third doses for at risk groups.

There is no information yet on whether the variant leads to a change in Covid symptoms or severity – this is something South African scientists will be closely monitoring. Since there is a lag between infections and more serious illness it will take several weeks before any clear data is available on this.

sí, teams behind vaccines are likely to be working already on updating vaccines with the new spike protein to prepare for an eventuality where a new version might be needed.

A lot of the preparation work for such an update took place when the Beta and Delta variants emerged – although in those cases existing vaccines have held up well. This means research teams were already poised to create new versions of vaccines and have discussed with regulators what additional trials would be required. sin embargo, it could still take about six months before updated vaccines, if required, are widely available.

Hasta ahora, the majority of confirmed cases have been in South Africa, with a handful in Botswana and Hong Kong. A further case was detected on Thursday evening En Israel – an individual who had returned from Malawi – and two other cases are suspected in the country.

sin embargo, given that there is community transmission in southern Africa, if there is a transmissibility advantage the new variant is likely to have already spread undetected to other countries.

Previous experience shows travel bans tend to buy time, pero, short of taking a zero Covid Acercarse, these measures will be unlikely to stop the spread of a new variant entirely.




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