We keep reading/hearing news that testing capability for COVID-19 is increasing, more tests are being run, and now Abbot labs has launched a test with a turnaround time of <15 minutes. Abbot says they will be distributing on the order of 50,000 tests per day. Lab Corp says they can run 20,000 tests per day. Quest Labs cite a similar number. So it seems that the testing problem has been licked, right? Well, not so fast. In the real world, testing is still in short supply, and it still typically takes days to get results.
WHY? WELL, IT GETS COMPLICATED. Basically there’s still a shortage of testing supplies—e.g. the swabs for the nose or throat, the solution the swabs go into, the lab personnel and equipment to run the test. It requires hours of labor by skilled lab technicians to run the tests, so the increasing number of specimens being sent for testing results in a bottleneck. Today on the radio we heard that Quest reports they have a backlog of 115,000 tests waiting to be run. In our practice, the turnaround time for results from various labs, including Quest and Lab Corp, was 3-5 days, but recently a test sent to Quest took 8 days. The Metropolitan Health District reports a 7 day turnaround time on results from their drive-through testing center.
IT’S NOT JUST CLINICS but also hospitals that are having trouble getting tests done with timely results. Many hospital labs don’t have the capability to do their own testing, so they’re sending their tests out to private labs with a slow turnaround time. Though the Methodist hospital system runs their own tests with results in 4-5 hours, their tests have been in very short supply (we’re told that is changing this week). The rapid new Abbott test should help with the problem of slow turnaround time, but it will be in high demand by hospitals and health departments, who must in any case first get the platform (analyzer machine) on which the test is run. Those who do have the test are prioritizing them for pregnant patients and acutely ill hospitalized patients. There’s a lot of scrambling to see who will get the tests first, but we don’t expect either the tests or the analyzer machines to be available to doctors’ offices for months (see Dr. Thornton’s earlier blog post on that.) The Washington Post had a good summary of the issues at hand. Basically, it’s the wild west out there:
WE’RE LEARNING ABOUT ANOTHER ISSUE WITH TESTING. Not surprisingly, the sensitivity of the tests (likelihood that they will detect the virus if it’s present), is not great—it seems they fail to detect the virus about 1/3 of the time. So, while a positive test means you almost certainly have the disease (because the tests are very specific), a negative result means does not guarantee you don’t have it. Dr. Thornton found this article to illustrate the point:
SO… IF IT WALKS LIKE A DUCK and quacks like a duck, in the case of COVID-19, assume it’s a duck (even if it says it’s not). That is to say, if you or your doctor thinks you may have COVID-19 (fever, fatigue, dry cough) you should assume you have it, even if your test (eventually) comes back negative. Other less common symptoms are: chest pain, muscle aches, headache, runny nose, loss of appetite, nausea, diarrhea, loss of smell and loss of taste. That means you should isolate yourself for the protection of others, starting from WHEN YOU GET SICK rather than waiting for your test result, follow up closely with your doctor, and let us know if you’re feeling short of breath or extremely ill. In the latter case, you will be directed to the emergency room. If you are sick at home, take Tylenol/acetaminophen for your pain or fever. Typically, out patients are not treated with hydroxychloroquine. Here is the protocol from the University of Washington which has had (unfortunately for them) lot’s of experience with treating Covid-19 patients.