The first U.S. death known to be from COVID-19 occurred on Feb. 6 — nearly three weeks before deaths in Washington state that had been believed to be the country's first from the coronavirus, according to officials in Santa Clara County, Calif. The person died at home and at a time when testing in the U.S. was tightly limited not only by capacity but by federal criteria.

The person is one of three people posthumously identified as dying from COVID-19 in Santa Clara County, after the medical examiner-coroner carried out autopsies and sent samples to the Centers for Disease Control and Prevention. The other two deaths took place on Feb. 17 and March 6.

"These three individuals died at home during a time when very limited testing was available only through the CDC," the county's health department said as it announced the findings. "Testing criteria set by the CDC at the time restricted testing to only individuals with a known travel history and who sought medical care for specific symptoms."

The Bay Area county, which had previously reported its first COVID-19 death on March 9, says it will likely identify more coronavirus deaths as its investigation continues.

Revelations about the deaths in early February underscore a point that public health officials often make when talking about a viral outbreak: that it's difficult, if not impossible, to get an accurate real-time picture of a disease's actual impact. By the time test results and statistics emerge, experts say, the information is weeks out of date.

At the time of the person's death on Feb. 6, the first known death outside of China had only been reported less than a week earlier, in the Philippines. U.S. cases then numbered in the tens, not the thousands.

Two days before the death in Santa Clara, the Centers for Disease Control and Prevention was urging people to wash hands and take other precautions to curb transmission of the virus. But the agency also said via Twitter, "CDC does not currently recommend the use of facemasks to help prevent novel #coronavirus. #2019nCoV is not spreading in communities in the US" – two positions it later reversed, as the disease's global impact grew.

At the start of February, COVID-19 had not yet been declared a pandemic and it didn't yet have an official name; it was still mainly known as the "2019 novel coronavirus."

By the end of February, President Trump announced the first U.S. coronavirus death had occurred on Feb. 28. Within days, officials in King County, Wash., said two people had died from the disease earlier, on Feb. 26. And they noted that they were seeing signs of community spread of the virus, as people were being hospitalized without having any known exposure to it.

The U.S. has now confirmed more than 825,000 COVID-19 cases, including 45,000 deaths, as of Wednesday morning, according to data compiled by Johns Hopkins University.

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