U.K. Covid Cases at Highest Level as Immunity Wanes, Study Finds

Covid-19 infections in England reached their highest level in March since the pandemic began, driven by the omicron subvariant BA.2 and waning immunity among older adults, according to a new study. The overall Covid prevalence rate more than doubled last month from February when infection rates were falling from the omicron-led January peak, the React-1 study led by Imperial College London found. Since then the emergence of BA.2 -- a more-transmissible version of omicron- has accelerated new infections and become the dominant strain in England, accounting for about 90% of the samples that tested positive. The higher infection rates may result in an increase in hospitalizations despite the higher levels of vaccination among the population, said Paul Elliott, director of the React program, and chair in Epidemiology and Public Health Medicine, Imperial College London.