London has the highest rate of Covid in England amid the rapid spread of the JN.1 variant, analysis revealed on Thursday.
The UK Health Security Agency (UKHSA) estimate that around 6.1% of Londoners had the virus as of December 14, by far the highest proportion of any region.
Prevalence in the capital is three times higher than a month ago, according to the UKHSA’s winter infection survey.
The study collected data through self-reported lateral flow test results and questionnaire responses from around 150,000 participants across England and Scotland.
Around 4.2 per cent of people in England and Scotland were estimated to have the virus as of December 14 – the equivalent of one in 24 people.
Prevalence rates were highest among people aged 18-44.
Professor Steven Riley, Director General for Data and Surveillance at UKHSA, said: “At this time of year, the cold weather, shorter days and increased socialising mean that the potential for transmission of respiratory viruses like Covid-19 is particularly high. This, as well as the possible impact of new variants, means it's not unexpected to see cases increasing.
“If you are showing symptoms of Covid-19 or other respiratory illnesses, you should try to limit your contact with other people as much as possible, especially those who are older or more vulnerable.”
He added: “It is important that those people who are most at risk of severe illness and hospitalisation as a result of COVID-19 come forward for their seasonal vaccination to make sure they have the best possible protection this winter. You can get a vaccine through your GP, by booking with a local NHS vaccination service, or you can find a COVID-19 vaccination walk-in site.”
It comes a day after the World Health Organisation classified the JN.1 Covid strain as a “variant of interest” amid rising cases in the UK.
JN.1 makes up around 7% of positive Covid tests analysed in a lab, according to the UKHSA.
In a statement released on Wednesday, the WHO said they would continue to investigate the variant but that it carried no greater risk of death or hospitalisation.
JN.1 is a subvariant of Omicron, which became the dominant global variant of Covid in winter 2021. It has been found in countries across the world including China, the UK and the United States.
The WHO said the risk to the public remains low but that infections could rise this winter.
"It is anticipated that this variant may cause an increase in Sars-Cov-2 [coronavirus] cases amid a surge of infections of other viral and bacterial infections, especially in countries entering the winter season," the agency’s risk assessment says.
It is not known whether JN.1 is more capable of evading immunity offered by vaccines, the WHO added.
JN.1 is currently the fastest-growing variant in the US.
Earlier this month, the US Centre for Disease Control and Prevention (CDC) said that JN.1 makes up about an estimated 15 per cent to 29 per cent of cases in the US as of December 8, according to the agency's latest projections.
