New UK Covid variant may be less likely to cause symptoms, study shows

According to the study, which was conducted by Imperial College London and Ipsos MORI, the new coronavirus variant, dubbed AY.4.2, two thirds of people infected with it reported "any symptom" against 75% of those infected with the dominant strain in the country, known as AY.4.

Furthermore, just a third of those who became infected with the AY.4.2 subvariant had "classic Covid-19 symptoms" versus half of those sick with AY.4.

Previous studies had pointed to the possibility of AY.4.2 being slightly more contagious than its forebear, but whether it caused more serious symptoms remained unknown.

The study, which had been commissioned by the UK's Department of Health and Social Care, looked at swab samples from 100,000 people in England.

AY.4.2 represented 12% of all new cases of the virus detected between 19 October and 5 November, having doubled in prevalence over the preceding two months.

Nonetheless, in remarks to Science Media Future, Dr. Simon Clarke cautioned that: "The data do not indicate the severity of those symptoms or who they occur in. If these AY.4.2. infections occurred in younger people or in communities where vaccine uptake is relatively high, these factors could account for the observed difference."

He further pointed out that even if it were less able to cause disease, the new subvariant would likely still be more virulent than the variants that had triggered lockdowns in the UK.

Clarke also expressed alarm about the fact that as per the study's results, one in 20 school age children in the UK had already been infected with the coronavirus, although that situation might improve with better vaccine rollout and uptake, and if a second dose were eventually authorised for that age group.