Los Angeles County is seeing a steady increase in cases driven by a new version of the Omicron COVID strain
The BA.2 subvariant now accounts for 84% of sequenced specimens in the County for the week ending April 2. This increase mirrors what officials are seeing across the country, as this highly infectious subvariant has also been identified in many cases across the U.S., according to the Centers for Disease Control and Prevention (CDC).
BA.2 is a descendent of the earlier super-contagious "stealth omicron" and has quickly gained ground in the United States.
BA.2.12.1 was responsible for 29% of new COVID-19 infections nationally last week, according to data reported Tuesday by the U.S. Centers for Disease Control and Prevention. And it caused 58% of reported infections in the New York region.
The variant has been detected in at least 13 other countries, but the U.S. has the highest levels of it so far. Scientists say it spreads even faster than stealth omicron.
Cases are rising in places with increasing levels of the BA.2.12.1 variant, such as central New York, suggesting something about it is causing it to out-compete others, says Eli Rosenberg of New York state's health department.
It appears a similar pattern will likely play out nationally, says Kirsten St. George, director of virology at New York state's Wadsworth Center Laboratory.
In Los Angeles, the increases in case numbers have not translated to increases in severe illness, with hospitalizations and deaths remaining low and slightly decreasing. Over the last seven days, the average number of people hospitalized daily is 222, a 20% decrease from two weeks ago when the average number of people hospitalized over the previous seven days was 276. Deaths also saw a small decrease, with the average number of daily reported deaths this past week at 10, a 28% decrease from two weeks ago when the average number of daily reported deaths over the previous seven days was 14.
Scientists are trying to figure out other aspects of BA.2.12.1, including whether vaccines are as effective against it as previous variants. Los Angeles officials said anecdotal data suggests vaccines continue to provide protection. For the week ending April 8, unvaccinated people were three times more likely to be hospitalized compared to fully vaccinated residents, and six times more likely to be hospitalized than those fully vaccinated and boosted. And the likelihood of dying was also 16 times higher for unvaccinated residents compared to residents who were fully vaccinated for the week ending April 1.
Laura Ungar contributed to this report.
