UCLA researchers say there was a significant increase in patients with coughs and acute respiratory illnesses at UCLA Health hospitals and clinics beginning in late December. They say this could mean that COVID-19 was in the area months before the first cases were identified.
"We knew early on that there were some early deaths where autopsies showed potential COVID infections in the month of January, so I can't speak to whether we are convinced yet today that it was milling around California in December," said Dr. Mark Ghaly, secretary of California's Health and Human Services.
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This sudden spike in patients with these symptoms, which continued through February, represents an unexpected 50% increase in such cases when compared with the same time period in each of the previous five years.
The findings, the study authors say, demonstrate the importance of analyzing electronic health records to monitor and quickly identify irregular changes in patient populations. The researchers' approach, in which they focused not only on hospitalization data but also on data from outpatient settings, may help epidemiologists and health systems detect future epidemics sooner.
The study appears in the peer-reviewed Journal of Medical Internet Research.
Meanwhile, Los Angeles County says it is investigating to make sure businesses and workplaces are safe, and it is also checking hundreds of complaints from the Labor Day weekend.
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"The numbers that we have been seeing in terms of compliance are better than we have seen in the past when we first started," said L.A. County Health Officer Dr. Muntu Davis. "I do think that this is a reflection of businesses really understanding and, you know, coming into a compliance."
California announced progress in the battle against COVID-19 in regard to testing. The state says test results are getting faster and labs are now turning them around on an average of 1.3 days.
And as wildfires in California force evacuations and people move to shelters or with family and friends, officials urge people to be vigilant and always use masks.
City News Service contributed to this report.