Scientists are to increase surveillance for new coronavirus mutations amid concerns that future strains of the virus could develop at least partial resistance to antibody treatments and Covid-19 vaccines.

There is no evidence that the mutations seen so far could help the virus evade vaccines or treatments now in development, but genetic analysis of circulating strains suggests that partially-resistant variants can emerge and spread among humans.

In a paper drawn up for the government’s Sage committee of experts, the UK Covid genomics consortium (Cog-UK) reports that a number of mutations have cropped up in the crucial “spike” protein which covers the virus like pins in a pin cushion and allows the pathogen to invade human cells.

Because many vaccines use the spike protein to generate immunity against the virus, mutations that subsequently change the spike can affect how well that immunity works.

“Anything that affects the spike protein can potentially change how either natural immunity or vaccine-induced immunity responds to the virus,” said Jeffrey Barrett, a geneticist and member of the consortium at the Sanger Institute near Cambridge.

The coronavirus that causes Covid-19 is genetically fairly stable, but it still acquires mutations, creating a multitude of lineages that geneticists can use to track the virus around the world and from outbreak to outbreak. By chance, some lineages will pick up mutations in the spike protein, a process called “antigenic change”. Many of these are likely to make the virus worse at spreading, but others may be neutral or even improve the virus’s ability to infect.

The potential risk comes if the virus accumulates mutations in the spike protein that change it enough for antibody treatments and vaccines to lose their potency. This could be most problematic for so-called monoclonal antibody treatments, of the type given to Donald Trump, where patients are infused with a mixture of two different types of antibodies. Vaccines tend to induce a greater variety of antibodies, so even if some are ineffective, the rest should still target the virus.

Image Credit:  Phil Noble/Reuters

Post by Amanda Scott, NA CEO.  Follow her on twitter @tantriclens

Thanks to Heinz V. Hoenen.  Follow him on twitter: @HeinzVHoenen

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