Covid cases rise in north-eastern US, driven by the BA.2 subvariant

Covid cases are on the rise in the north-eastern part of the US, as many Americans travel and gather together for spring break and religious holidays.

The rise is being driven by BA.2, a subvariant of Omicron which is more transmissible than its sibling BA.1, and was responsible for an estimated 86% of new Covid-19 cases nationwide last week, according to the US Centers for Disease Control and Prevention (CDC).

Case counts across the US remain comparatively low, and rates are still falling in several parts of the country. But the US overall is seeing a tick upward in numbers, with an average of 30,000 people testing positive in the US each day, compared with about 26,000 last week, according to the CDC.

Philadelphia was the first city to reinstate its indoor mask mandate on Monday, in an attempt to stave off a rise in hospitalizations, which a University of Pennsylvania model predicts may rise in coming weeks. The city will also add requirements to show proof of vaccination if cases continue rising.

The White House renewed its mask mandate for public transportation for another two weeks on Wednesday.

Several universities across the US, including Columbia, American, Georgetown, George Washington, Johns Hopkins and Rice, are also returning to mask mandates on campus.

Deaths are holding steady at slightly above 500 each day. Doctors hope that access to treatments, including monoclonal antibodies and antiviral medications for those who are most vulnerable, may stem a rise in Covid-related hospitalizations and death.

But federal funding for these medications is running out, without a new deal in place yet. Only 1.5m of a planned 10m courses of the antiviral Paxlovid, for instance, have been delivered to states and territories.