Health

The Telegraph

Covid-19 may have become more contagious as it has mutated, the largest genetic study carried out in the US into the virus has suggested, as scientists warn it could be adapting to interventions such as mask-wearing and social distancing. One variant of the novel coronavirus is now one of the most dominant in America, accounting for 99.9 per cent of cases in one area studied. The paper concluded that a mutation that changes the structure of the “spike protein” on the surface of the virus may be driving the outsized spread of that particular strain. Researchers have been sequencing the genomes of the coronavirus at Houston Methodist, one of the largest hospitals in Texas, since early March, when the virus first appeared in the city. To date, they have documented 5,085 sequences. In the first wave of the outbreak in Houston around March, some 71 per cent of the viruses were characterised by the mutation, which originated in China and is known as D614G. By the second wave, which began in May and is ongoing, the D614G mutation leaped to 99.9 per cent prevalence. A tiny tweak in the spike protein of the dominant variant switches an amino acid from aspartic acid to glycine. The new mutation appears to be outdistancing all of its competitors. The graphic below explains more.