Neither of the sub-strains have been named yet but AY.4.2 could be branded 'Nu' if it is considered a threat by the World Health Organization (WHO), which is keeping tabs on its spread.ĪY.43 was first detected around July when Delta was taking off, and there is no evidence to suggest it is more infectious or better able to evade vaccines than other variants. Latest figures show the AY.4.2 subvariant makes up around 11 per cent of all new cases in England and has been spotted in all but five boroughs: Craven, Burnley, Hyndburn, Melton, and Oadby and Wigston. Scientists today insisted there was 'no need' to be concerned about the strain, saying there was no evidence yet that it was more transmissible or better able to evade vaccines.īut it comes after a rapid uptick in cases of AY.4.2 - another descendant of the original Delta strain - which is being kept under close review by British and international scientists. It makes up around one in 24 cases in the country after first being detected in mid-July and has grown consistently ever since. The new sub-strain, called AY.43, has already been spotted 8,138 times in England, according to the latest data from one of the country's largest surveillance centres. Another offshoot of the Delta variant is spreading in Britain, Covid-tracking experts revealed today - as the virus' other concerning subvariant continues to spread.

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