Why California virus cases exploded
It wasn’t long ago that COVID-19 infections in California were coming at half the rate of the nation, per capita. Just flip the calendar back a month. Even this past weekend, California was seeing relative success in containing the virus compared to other states.
But just in the past few days, California’s case counts have exploded. Twenty thousand from a handful of counties Sunday. Thirty thousand each of the past two days. A daily average on pace to double in a span of nine days. As the surge here has grown larger, California’s infection rate has nearly pulled even with the national average, for the first time in more than three months.
The Golden State has now reported about 62.8 daily cases per 100,000 residents over the past week, a rounding error away from the national rate of 63.1 over that time. There are still 33 states with higher rates, but California is slowly climbing the list — its growth rate is outpacing the country as a whole, up 77% week- overweek vs. 28% nationally.
So, what happened? “I think that the reality is that it reflects a variety
of forces at work,” said Dr. Arthur Reingold, an infectious diseases expert and the chair of epidemiology at UC Berkeley.
Nine months in and facing new shutdowns, Californians are suffering from pandemic fatigue and less compliant with public health measures, Reingold said. Colder weather also pushed more people indoors, where the virus spreads much more easily. Add on Thanksgiving gatherings, and you’ve got a situation “pretty much what any reasonable infectious disease epidemiologist could predict,” Reingold said.
Case numbers don’t tell the whole story, though.
More people in California
are getting tested for the virus than ever before. Over the past week, California has tested an average of nearly 250,000 people per day, a 25% increase from the previous week. More of those tests are also coming back positive: 10.1% of all tests in the past week, the state’s highest positivity rate since testing became widely available.
Although California ranks 17th in testing per capita, with about 630 daily tests per 100,000 residents, it is well ahead of the nation in its efforts to expand testing. While the U.S. is testing about 15% more than it was three weeks ago, California has increased its testing capacity by 45% in that time.
“Testing capacity has gone through the roof,” said Dr. George Rutherford, an infectious diseases expert at UC San Francisco. “I think some of it is just increased case finding. But, you know, at the end of the day, there’s just a load of cases.”
Rutherford echoed Reingold in his on-the-ground observations about pandemic fatigue: In recent weeks, more people have been crowding city sidewalks and enjoying al fresco meals.
If those prove to be vectors of transmission, Gov. Gavin Newsom’s new stayathome order, which forces restaurants to close their patios in affected regions, could make an impact. State health officials have urged Californians to avoid gathering with people outside their household altogether.
But with multiple days of gobsmacking totals — and, experts believe, more to come — there are already tens of thousands of infections in the state playing out right now. Many will recover at home without incident. But even the small portion projected to arrive in hospitals around the state could push intensive care units over the edge.