Rising Covid-19 infections among schoolchildren in England could trigger a resurgence of Omicron-variant infections among older people, researchers behind a major community-based coronavirus study have warned.
The React-1 study from Imperial College London, published on Wednesday, estimated that 4.4% of people in England were infected with Covid-19 between January 5 and 20, the highest level since the the study began in May 2020, based on test results from about 100,000 people.
Some 7.8% of primary school children had coronavirus during the same period, more than any other age group. Among those over 75, the most vulnerable age group, the prevalence was 2.4%.
While the reproduction number, or R-value, was 0.95 for the entire population, suggesting that the overall epidemic was on the decline, the R-value for children aged 5 to 17 was 1, 17, suggesting infections were on the rise.
“There is good news in our data in that infections declined rapidly in January,” said Paul Elliott, professor of epidemiology at Imperial College London and lead author of the study. “But they are still extremely high and may have recently stagnated at very high prevalence.”
As the infection is decreasing in adults but increasing in children, he warned of the “risk that it could spread from these children to this group of adults”.
Jenny Harries, chief executive of the UK Health Security Agency, said the study “reaffirms that, although case rates have slowed recently, prevalence is still high”.