A second case of COVID-19 with an unknown origin has been identified in Santa Clara county, California on Friday. This indicates to health experts that the novel coronavirus — which causes the disease COVID-19 — is likely spreading through more than one community in the US.
The Washington Post first reported news of the second case of community transmission in the US — a 65-year-old woman who had no known history of travel to any of the countries that have been hardest-hit by the disease.
So far, more than 84,000 cases of COVID-19 have been confirmed around the world, and more than 2,800 people have died of the respiratory disease. Most of these cases are concentrated in China, where the virus was first identified, but the disease has since spread around the world, with South Korea, Italy, Japan, and Iran among the hardest-hit.
Despite the global spread, the US has lagged in testing people who showed symptoms of the disease. Until this week, the Centers for Disease Control and Prevention had only tested people who had traveled to one of the most affected areas or had been in close contact with someone who had been diagnosed with the disease. In the case of the first patient who had COVID-19 of unknown origin, the hospital where she was being treated immediately requested a CDC test on February 19th, when the patient arrived. The CDC didn’t get around to testing the patient until February 23rd. The positive test results were announced on February 26th.
The CDC’s restrictive criteria coupled with a complicated test and convoluted rollout led to an intense public backlash. The agency expanded their testing requirements on Friday to include people who had traveled to a wider swath of geographic areas during the past 14 days. It also began allowing testing for people who had both severe symptoms and no diagnosis of other diseases like the flu.
The case announced in California today appears to be part of that last group. The woman apparently had no connection to any patients who were confirmed to have the disease, and had also not traveled to any area where the virus is known to be circulating. That means she may have gotten it from someone in the US who has not been diagnosed. Both cases were diagnosed in the San Francisco Bay Area, a geographical region that includes nine counties. The first case, in Solano County, was in the north part of the region; the second case, in Santa Clara, is about 90 miles away.
“I think there’s a strong possibility that there’s local transmission going in California,” said Jennifer Nuzzo, senior scholar at the Johns Hopkins Center for Health Security, in an interview with The Washington Post. “In other words, the virus is spreading within California, and I think there’s a possibility other states are in the same boat. They just haven’t recognized that yet.”