There are already dozens of cases across almost half of the U.S. of a new Covid subvariant that's even more contagious than the already highly transmissible omicron variant. The subvariant is 1.5 times more transmissible than the original omicron strain, referred to by scientists as BA.1, according to Statens Serum Institut, which conducts infectious disease surveillance for Denmark. The U.K. Health Security Agency on Friday said BA.2 has a "substantial" growth advantage over the original omicron. However, a preliminary assessment found that BA.2 doesn't appear to reduce the effectiveness of vaccines any more than the original omicron. Maria Van Kerkhove, the WHO's Covid-19 technical lead, warned on Tuesday that the next Covid will variant be more transmissible.
