Officials in San Diego have repeatedly said that local hospitals are steadily increasing their COVID-19 testing capacity. But the number of completed tests reported by the county does not back up their claim.
On Tuesday, Gov. Gavin Newsom said increasing testing capacity is the most important factor in ending the state’s current lockdown. Epidemiologists and doctors have echoed that claim. Widespread testing allows public health officials to better track the spread of a virus and clear people for going back to work.
And yet, testing has gone down in the last week, according to county data analyzed by Voice of San Diego.
Over the last seven days, the county has reported 6,715 completed tests. In the seven days prior, officials reported 9,982 tests. And in the week before that, 6,890 tests were reported.
This is despite repeated assurances that local testing capacity has been on the rise.
When asked why testing might be down, Dr. Eric McDonald, a county public health officer, gave two reasons.
In some cases, it can take up to 12 days for the county to receive test results from a commercial lab, McDonald said. (Health care providers often send samples out to commercial labs all over the country. The results are then sent back to the health care providers and county officials.) This lag could account for some variance in how many tests are reported, he said.
But commercial lab results have lagged since San Diego’s outbreak started more than a month ago. Since the lag has been consistent, it’s unclear how it might be affecting week-over-week results.
Commercial labs are not the only way to get test results. Local hospitals, as well as the county public health department, can also complete tests. It is the testing capacity of local hospitals that county officials have repeatedly said is growing.
Local hospitals do not appear to be testing at their full capacity, McDonald acknowledged, as the second reason testing could be down. That additional testing capacity, if it isn’t being utilized, “needs to be used,” he said.
But county officials have issued conflicting guidance on this point.
The most recent guidance by local public health officials instructs hospitals to only perform tests on people with “significant respiratory illness.” The advisory continues, “Patients who have mild illness and do not belong to a priority population do NOT (sic) need to be tested.”
Only testing people with the worst symptoms is not the way to bring Californians back to work. Testing people who have mild symptoms and even those with no symptoms is the only way to end the lockdown, health experts agree.
I asked McDonald how many tests San Diego would need to do every day to aggressively move out of social isolation practices. “It’s gonna easily be on the order of tens of thousands, and that’s more than we have now,” he said.
For the last three weeks, the county has averaged 1,123 tests per day.
Local hospitals alone have the capacity to do 1,200 tests a day or more, officials have said. That does not count the many tests currently done by commercial labs.
Public health officials could issue new guidance to hospitals, instructing them to begin testing patients more widely.
There could be myriad reasons hospitals are having trouble testing. Tests require special machinery and chemicals, known as reagents, as well as swabs to take samples. If a hospital is missing any part of the equation, workers can’t complete the test.
Workers also need personal protective equipment, like masks and gowns, to be able to take samples from patients. Protective equipment is also in short supply.
Newsom has pledged to increase testing capacity statewide. Abbott, a medical device company, has pledged to open 75 testing sites across the state, according to NPR.
New York has roughly half as many residents as California, but to date it has completed more than twice as many tests, according to the COVID Tracking Project.
Dr. Mark Sawyer, an infectious disease specialist at Rady Children’s Hospital, said he was surprised to learn that less testing took place countywide than in previous weeks. Rady as well as other local hospitals have increased their capacity, he said.
Sawyer described why so much testing is required to help bring people out of isolation.
“There will be rings of testing around a single test. Let’s say one known case has been in contact with 15 people. We test all 15. We find two positives. Both of those cases have been around 15 people each. Now we need to test 30 more people. You can see how it goes up pretty quickly,” he said.
San Diego’s curve has begun to flatten in recent weeks. But if officials ended social distancing without widespread access to testing, new cases could rapidly begin to spread. As long as testing continues to be available for only the most ill, it will be nearly impossible to know when it’s safe for people to come out of their houses.