Most states still aren't doing enough coronavirus testing

Most states still aren't doing enough coronavirus testing, especially those that have suffered from larger outbreaks, according to recent testing targets calculated by the Harvard Global Health Institute.

Between the lines: It's much harder to contain the virus once a lot of people have it — which is why we needed strong social distancing in the first place. But knowing who is infected is the foundation of containment going forward, and most states are still behind.

The big picture: Nationally, the U.S. needs to be doing about 900,000 tests a day, according to the Harvard estimate, which was released earlier this month.

• But not all states need to be doing the same amount of tests. The goal Harvard suggested for each state — the number of tests they should have done on May 15 — was calculated based on the size of its outbreak as of early May.
• That means that New York needs to be doing a much larger number of tests each day than Wyoming, even after accounting for the states' huge population discrepancy.

Why it matters: Most states have already begun reopening to some extent, even without key public health tools — like testing and contact tracing — fully built up.

• That increases the chance that the virus will spread undetected as people begin interacting with one another again.
• And these premature measures may just increase the number of tests a state needs, especially because the estimates were based on the assumption states would remain closed until May 15.
• “The moment you relax, the number of cases will start climbing. And therefore, the number of tests you need to keep your society, your state from having large outbreaks will also start climbing," Harvard's Ashish Jha warned.