The Trump administration announced Saturday that health insurers will be required to cover the cost of blood tests for antibodies that would signal past infection and current immunity to the novel coronavirus that causes Covid-19. This would be in addition to covering the cost of tests for current infection with the virus.
The regulatory announcement from the Centers for Medicare and Medicaid Services clarifies some ambiguities in recently enacted congressional legislation that was supposed to make testing free. The key points are an expansion to antibody testing and a clarification that services ancillary to the test (like the visit fee for an urgent care center) must also be covered.
Since tests have been in short supply continuously from the virus’s first arrival in the United States, many people who’ve been infected have never been tested. The tests are mostly being used for diagnostic purposes to facilitate the care of people experiencing severe symptoms. But to the best of the current knowledge, most cases of Covid-19 are relatively mild or even asymptomatic, and people with light symptoms have been urged to simply isolate themselves and stay home rather than burden the medical system or use up scarce tests.
Antibody testing can help people who believe they had a mild case in the past ascertain whether that’s what actually happened, and assess people who’ve recovered from Covid-19 for immunity. Identifying a corps of already-immune people who could assist the gravely ill without endangering themselves could be a key step to ameliorating the crisis, so there is a clear public interest in making the antibody tests as widely available as possible.
There are several different forms of blood test currently being rolled out, mostly under emergency use authorization orders from the Food and Drug Administration. Some of the tests can be conducted in about 10 minutes with a simple finger-prick (I got one on Friday; no immunity) and will be relatively easy to deploy widely in the near future.
Unfortunately, as Vox’s Brian Resnick has explained, it’s not totally clear at this point that past infection with the coronavirus does, in fact, instill long-lasting immunity. There are reports of recovered patients becoming reinfected, and it’s possible that the antibody response to mild or asymptomatic cases is particularly weak. So while making the antibody tests as accessible as possible seems like an obvious call, even a successful testing rollout may not deliver the results the world is hoping for.