(TNS) - A one percentage point increase in the positive rate for local COVID-19 testing appeared in county reports Thursday.
For the first time since May 20, four percent of test results returned in a single day were positive, with 142 new cases tallied and five new COVID-linked deaths announced.
Though a single day's number does not mean much, it came alongside reports from two large local medical providers that said they are seeing higher COVID activity in some locations than they were previously.
Dr. Eric McDonald, medical director of the county's epidemiology unit, said Thursday evening that while seeing numbers increase can be telling, it's difficult to draw conclusions without a much longer trend line. There can be a fair amount of variability in ratio of positive to negative test results, he said, depending on who is doing the testing. Tests performed by health providers on patients with symptoms tend to return more positives than those conducted at broad screening operations.
"If, on a particular day, we're getting a larger number of results from a health care system location like a hospital or a clinic, that could mean a higher number on a given day," McDonald said.
Higher numbers for a longer period of time, he said, would be necessary to say a trend is building.
"It would have to be sustained, and then we would need to understand if it was concentrating geographically," McDonald said.
Scripps Health and UC San Diego Health both confirmed Thursday that they have recently seen increased rates of positive tests. It seems clear that recent increases are not universal across the region. Sharp HealthCare, Kaiser Permanente and Palomar Health all said the percentage of positive cases coming out of their labs are flat.
Johan Otter, assistant vice president of ancillary services at Scripps, said Thursday afternoon that a still-small but noteworthy trend has appeared among emergency patients who recently visited the provider's northernmost hospitals in La Jolla, Torrey Pines and Encinitas.
"With COVID it has been kind of an undulating pattern up and down over time," Otter said. "We're wondering if we're starting to see the first signs of it slowly creeping up, but we can't say for sure."
Scripps Memorial Hospital Encinitas has now seen four straight days with at least one patient testing positive in its emergency department. The total number of cases is quite small — just seven — but it is the first time the facility has seen at least one positive test result for four straight days in several weeks. In the previous seven days — from May 28 to June 3 — Scripps Encinitas had eight positive tests compared to a total of three recorded during a similar span of seven days three weeks ago.
The numbers look positively mild compared to what has been going on at Scripps Mercy Hospital Chula Vista which tallied 30 positives in its ER over the previous seven days. But, unlike the nascent upward trend in Encinitas, positive tests are becoming less common at Scripps Chula Vista which had 51 positive ER tests three week ago.
UC San Diego Health declined to specify exactly how its positive case trend has changed recently, saying it would want a full two weeks of data before saying more.
At the moment, many are interested in whether or not Memorial Day Weekend might end up delivering a bumper crop of COVID cases. McDonald said contact-tracing efforts, which involve interviewing all who came in close contact with people who have tested positive, said that there has so far been only one cluster of cases directly connected to a Memorial Day celebration. That scenario, he said, involved a barbecue attended by 11 people. Five of those, he said, tested positive.
"That's the only one that we picked up out of that whole time period around Memorial Day," McDonald said. "We haven't really seen any big trends yet."
Though the median incubation period for novel coronavirus is five days with the maximum in most cases thought to be 14 days, it may take longer for people to actually reach out for medical help after they start experiencing symptoms such as fever, cough and shortness of breath.
Many coming across the border for care, most who are American citizens living in Mexico, McDonald said, are waiting far to long to get checked out. Many have died in Chula Vista emergency departments shortly after arriving because their disease has suddenly begun to progress rapidly, he said.
People may not realize, he said, how quickly this particular disease can take a person from feeling like they can manage to full-blown respiratory failure.
"You worry about that as a reason why we might not be seeing some of the cases yet if people are sitting home not realizing how bad it can get," McDonald said.
The additional 142 new COVID cases announced Thursday bring the regional total to 7,940. With five additional deaths announced Thursday, the total has reached 288.
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