What do we know about coronavirus? There will be mistakes

At the core of all scientific research lies an inflexible paradox. Urgency demands patience. Our progress has always come from our missteps. Medical history is one of rare successes sprinkled among participation trophies and frank failures.

Diagnostic tests have routinely required improvement. A reliable test for H.I.V. was not available until 1984 — three years after AIDS was described. Management of hepatitis C, the next national scourge, was hindered for more than a decade by a series of inaccurate tests. Even bacterial pneumonia remains hard to diagnose.

Therapies rarely work on the first try. We still have no treatment for the common cold, though many have been tried. Ditto West Nile, Zika and Epstein-Barr. The decision to prescribe oseltamivir (Tamiflu) must often be made before the diagnosis of influenza is confirmed. Even then its benefits are minimal.