BA.4 and BA.5 are newer Omicron strains recently classified as “variants of concern”, following an analysis that found that both were likely to have a “growth advantage” over BA.2. They are now believed to be the most prevalent variants in much of the UK, and the Office for National Statistics (ONS) said the latest increase in cases was “probably caused by infections compatible” with BA.4 and BA.5. A total of 1.4 million people in private households were estimated to have contracted the virus in the week beginning in July, up 43% from the previous week, according to the ONS. The number of people hospitalized with Covid is also showing signs of rising, although the number of reported coronavirus deaths remains low. According to data from Kei Sato of the University of Tokyo and his colleagues, BA.4 and BA.5 may have evolved to favor lung cell infection. Do you want a quick and specific update on the biggest news? Listen to our latest podcasts to find out what you need to know This differs from previous, milder variants of Omicron, which separate data suggest did not grow as well in cells derived from the lungs. Mr Sato told ITV News: “We have data suggesting that the BA.4 / 5 pin is more fusion [facilitates fusion] from pin BA.2. “In our previous Delta, BA.1 and BA.2 studies, higher fusion was closely linked to lung preference.” Total Covid infections in the UK have now returned to levels last seen in early May, but remain well below the record 4.9 million at the peak of the Omicron BA.2 wave in late March. Covid-19 cases have increased in all four nations of the United Kingdom. How are Covid levels in the UK? All four nations have seen an increase in cases. In England, 1.1 million people were likely to test positive for Covid-19 a week on July 6 – equivalent to about one in 50. Increasing each week from 797,500 or one in 70. Wales has seen infections rise to 64,800 people, or one in 45, out of 40,500 or one in 75. The virus is estimated to be more prevalent in Scotland, where 176,900 people were likely to have tested positive last week, or one in 30, out of 124,100, or one in 40. Northern Ireland has seen Covid-19 infections spread to about 42,900 people, or one in 45, from 27,700 or one in 65.
