The Government has renewed its calls for people to get vaccinated against Covid-19 after warning of the potential threat of future variants.
A new Delta variant, known as AY.4.2, or Delta Plus, is currently being monitored by Downing Street.
The descendant of the Delta variant has been slowly increasing in case numbers in the UK, although there is currently no evidence that it spreads more easily.
Scientists have said Delta Plus carries two characteristic mutations in the spike - Y145H and A222V - both of which have been found in other coronavirus lineages since the start of the pandemic.
However, these strains have remained at a low frequency until recently, with the first to carry both mutations being sequenced in April 2020.
Health Secretary Sajid Javid has said that new variants are being identified “all the time” and, at the moment, Delta Plus poses no greater threat than any other variant.
But Mr Javid urged people to get vaccinated against Covid-19, and take up the offer of a booster dose, to help keep infections under control after warning cases could rise to 100,000 per day this winter.
He said: “While there’s no reason to believe at this point that AY.4.2 poses a greater threat, the next variant, or the one after that, might do.
“So we need to be ready for what lies around the corner. This means our ongoing programme of booster jabs is so important, and this winter we’re prioritising those most in need.”
While the government has said it is “keeping a close eye” on cases, where in the UK has recorded the most Delta Plus cases so far?
Analysis of Covid-19 samples in England reveals the areas where the highest number of AY.4.2 variant has been identified.
Data is based on the number of confirmed cases of the Delta Plus variant from Covid-19 tests that were genomically sequenced in the week to 9 October. These figures do not show the overall number of Delta Plus cases, as not all tests are genomically sequenced.
These are the 15 areas with the highest number of Delta Plus cases, based on the data available.