Friday 1 July 2022 03:33 PM New York City's Covid test positivity rate reaches 10% for first time since ... trends now

More than one-in-ten Covid tests in New York City are coming back positive for the first time in nearly six months - as officials fear new strains of the virus taking hold in America will result in another summer surge.

The Big Apple's Covid-19-test positivity rate reached 10.3 percent, according to most recently available data from NYC Health. It's the first time the mark has eclipsed 10 percent since January, when the city was ravaged by the Omicron variant.

While raw figures remain low - the 3,400 cases per day the city is averaging is dwarfed by the tens of thousands reached during the original Omicron surge - some fear case figures are no longer reliable because of the prevalence of at-home testing and asymptomatic cases.

The reason for the jump in case-positivity is believed to be the BA.5 Omicron sub-lineage, which some are describing as the worst version of the variant yet.

Daily case figures are beginning to creep upward across the U.S., with daily case figures jumping 12 percent over the past week to 112,781 per day. Deaths have remained steady at 376 per day, though.

The most recently available data from New York City health officials is from June 27. Over the course of 11 days, the city's Covid positivity rate rocketed from 7.5 percent on June 16 to 10.3 percent on the 27th.

Rocketing case positivity also correlates with the rise of two mutant virus strains that are starting to become dominant.

The BA.5 variant now makes up 36.6 percent of sequenced cases, according to the Centers for Disease Control and Prevention (CDC), only trailing BA 2.12.1 (42 percent of sequenced cases) as the nation's most prevalent strain. BA.4, which shares many of the same traits as BA.5, makes up 15.7 percent of cases.

Every single sequenced cases in the U.S. is a form of the Omicron variant as the highly infectious strain that emerged in late 2021 has snuffed out other versions of the virus.

The once-dominant BA.2 'stealth' variant now makes up less than six percent of Covid cases in the U.S. The original BA.1 Omicron strain is no longer being detected.

The strains, which now make up more than half of the nation's Covid cases, have alarmed health officials after early data from South Africa showed that natural immunity a person has from a previous infection is not as effective against them as it is other strains.

While their rise has not yet impacted national case figures, some experts are warning that more localized outbreaks are on the way.