The most contagious new XE variant of COVID19 which has spiked in UP over the past couple of weeks has now been reported in Mumbai along with a case of Kappa variant as well.

Results of the 11th genome sequencing declared by the city civic body Brihanmumbai Municipal Corporation (BMC) reflected the same.

The individual who tested positive for the XE variant was a fully vaccinated 50-year-old women with no comorbidity and asymptomatic, BMC officials said. She had come from South Africa on February 10 and had no prior travel history.

On arrival, she had tested negative for the virus. XE is a "recombinant" which is a mutation of BA'1 and BA.2 Omicron strains. Recombinant mutations emerge when a patient is infected by multiple variants of Covid.

The variants mix up their genetic material during replication and form a new mutation, UK experts said in a paper published in British Medical Journal.

In its latest sero survey report, BMC said that of the 230 samples sent for sero survey from patients from Mumbai, 21 were subsequently hospitalized. However, none needed oxygen support or intensive care, the report said.

The new mutation appeared to be around 10 per cent more transmissible than the BA.2 sub-variant of Omicron, as per the World Health Organisation.

Until now, the BA.2 sub-variant of Omicron was considered the most contagious strain of Covid-19. If this new research is confirmed, it would make XE the most transmissible Covid-19 mutant yet.