You’ll Probably Never Know If You Had the Coronavirus in January

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There is no doubt that the coronavirus was spreading in the United States in January. We can at least start with that. Recently, California’s Santa Clara County reported that bodily tissues from a woman who died on February 6 tested positive for the coronavirus. She had not traveled outside the country, and based on what is known about the virus, she must have picked it up by January 31; in all likelihood, she was infected a week or two before that. The virus, it turned out, had been spreading in the United States well before we suspected, and weeks earlier than previous official estimates of community transmission had accounted for.

Of all the things we still don’t know about SARS-CoV-2—How far can it travel through the air? What treatments can tame it? How many people will it kill?—the number of people who might have been infected with the virus in January has held a special allure. A reliable estimate could help determine just how bad the United States’ botched early response to the pandemic was. We already know that the government failed to detect as many as 28,000 infections by March 1, so just how late to the game were we? Knowing more about January infections could also offer clues to the true number of Americans who have now been infected—thanks to a shortage of tests, the official count of 1.2 million is almost certainly too low. A firm number could inform our strategies for preventing subsequent waves of COVID-19 from becoming even more disastrous than the first.

Curiosity about January