New Covid Variants Nimbus and Stratus Spread Rapidly, Prompting Health Warnings
Across both sides of the Atlantic, new COVID-19 variants are spreading with a speed that has unsettled public health observers. The variants known as Stratus (XFB) and Nimbus (NB.1.8.1) are gaining ground in both United Kingdom and the United States, driven by mutations that enhance their ability to transmit efficiently from person to person. In the UK, test positivity rates have climbed past 8 percent, while in the United States, rising viral loads detected in wastewater surveillance point to widespread…