* Imperial study finds September rise in child COVID cases
* Epidemic shrinks in younger to middle-aged adults
* Health minister: things feel quite stable (Adds reaction)
By Alistair Smout
LONDON, Oct 14 (Reuters) - COVID-19 infections in children in England rose in September after schools returned from summer holidays, helping to keep cases high even as there was a fall among adults, a large prevalence study showed on Thursday.
Infection numbers in Britain are currently much higher than in other western European countries, but have not risen above summer levels following the return of schools in September in England despite higher infection rates in children.
The REACT-1 study, led by Imperial College London found that prevalence in 13 to 17-year-olds was 2.55% between Sept 9-27, with prevalence in those aged 5 to 12 at 2.32%. Prevalence for every adult age group was estimated below 1%.
"Prevalence was high and increasing in school aged children during September," Paul Elliott, director of the study, told reporters, adding that increased vaccination uptake in school-aged children and adults would help limit transmission.
The study, which analysed 100,527 valid swabs, found that the epidemic was growing among those 17 and under, with an estimated reproduction "R" number of 1.18. An R number above 1 implies exponential growth, while a number below 1 implies the epidemic is shrinking.
The epidemic was estimated to be shrinking in 18-54 year olds, with an R number of 0.81, while the epidemic was broadly steady among those over 55.
While around 90% of over 18s have had one dose of COVID-19 vaccine, vaccination rates of children are much lower, and broad vaccination of those aged 12-15 only began last month.
"It just could have been avoided to have this large amount of spread amongst schoolchildren... if they'd done the vaccinations earlier," Dr Brian Ferguson of the University of Cambridge's Division of Immunology told Reuters.
He added that while it looked like transmission from children to adults was not going to be a big problem, there was uncertainty heading into the winter.
In daily figures, Britain reported 42,776 new COVID-19 cases on Wednesday, the highest number since mid-July, but health minister Sajid Javid played down the fluctuations in numbers.
"Overall things feel quite stable at this point. The numbers are a bit up, a bit down over the last few weeks," he told Times Radio, adding government strategy was working. (Reporting by Alistair Smout, additional reporting by Sarah Young; Editing by William Maclean, Toby Chopra and Emelia Sithole-Matarise)
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