Los Angeles Covid Test Positivity Rising Rapidly; Only Time Will Tell If Hospitalizations Follow Suit
Last week, the 7-day average daily number of new cases in the county was 878. By yesterday, the county was averaging more than 1,000 new Covid cases per day.
Rising even more than the daily case numbers is the 7-day average daily rate of people testing positive for the virus, a data point considered a more accurate indication of spread because, in addition to being an average, it accounts for rising and falling test numbers. That rate had been holding steady below 1%, but rose to 1.7% on Thursday and hit 2.4% Friday. The rate is still low overall, but more than double what it was one week ago and roughly triple what it was two weeks ago. That’s a big increase for a number that is a 7-day average.
The rising case numbers haven’t yet translated to a spike in hospitalizations and deaths, which is something optimists continue to point at as the region tries to get back to normal after the winter Omicron wave. The number of Covid-positive hospital patients in Los Angeles County actually sank today, and it’s been trending that way.
Last Friday, the number of Covid-positive hospital patients was 275. Today, the number stood at 228. That’s a 17% drop in one week. Of those patients, 31 were being treated in intensive care, down from 32 on Thursday. Another 13 virus-related deaths were also reported Friday.
The BA.2 subvariant, a more infectious offshoot of the Omicron variant that caused a winter surge in cases, is now the dominant strain of the virus in the county, according to public health officials. The latest data has it accounting for 67% of new infections, but that data is over two weeks old, so the variant likely makes up a much greater percentage of new cases by now.
There has been speculation that BA.2, while more transmissible, is also less virulent. In some regions a rise in BA.2-related cases has not been followed by a rise in hospitalizations and deaths. That difference from the winter Omicron wave is cause for cautious optimism. But it’s still too soon to call an all-clear on BA.2.
Throughout the pandemic, jumps in hospitalizations have generally followed increases in daily cases by about 2 weeks. Part of BA.2’s increased ability to infect people is thought to be a shorter incubation period, which means hospitalizations have been rising sooner, from between 10-14 days. So given that case numbers only began to rise in earnest in the past week, any resultant rise in hospitalizations would likely show up at the end of next week, or in the final week of April.
Indeed, while some regions seem to have avoided a rise in hospitalizations, the U.K. — which has often presaged trends stateside — did recently see a rise in both hospitalizations and deaths.
Closer to home, New York has begun to see a consistent rise in hospitalizations after a rise in infections and test positivity. The 7-day average number of hospitalizations in the state was about 2,000 in late March, according to data from Johns Hopkins University. It was over 5,600 as of Wednesday, the most recent day for which data is available.
One variable in the mix is whether daily testing, which is at one of the lowest ebbs in about a month, is accurately capturing the current wave of new cases. The difference between the rose in 7-day average test positivity and 7-day average case numbers would seem to support that suspicion.
Additionally, a new state study suggests the number of people in Los Angeles County who have been infected with Covid-19 during the pandemic is far greater than the number confirmed through standard testing. That’s due largely to the number of people who never developed symptoms and so never got tested, or who couldn’t access tests, or who tested positive at home and never reported the results.
City News Service contributed to this report.