Health officials announced on Feb. 26 that the latest confirmed case of COVID-19 in an individual in Northern California may be the country’s first case of human-to-human transmission from an unknown source.
The Centers for Disease Control and Prevention said in a statement on Wednesday night that the patient has no known sources of exposure, like close contact with confirmed carriers of the virus.
It added that the individual had “no relevant travel history” before the case was detected through the U.S. public health system.
“At this time, the patient’s exposure is unknown,” the agency said. “It’s possible this could be an instance of community spread of COVID-19, which would be the first time this has happened in the United States. Community spread means spread of an illness for which the source of infection is unknown.”
The agency added there is a possibility that the individual may have been “exposed to a returned traveler who was infected,” and will update the public as they get more information.
The California Department Of Public Health said that the unnamed individual is a resident of Solano County and is receiving medical care at UC Davis Medical Center in Sacramento County.
Hospital officials said in an email that the patient had been transferred to UC Davis Medical Center as a suspected virus patient on Feb. 19. However, the CDC did not immediately test the patient as they did not fit the “existing CDC criteria for COVID-19.” The CDC began testing four days later.
Due to precautions put in place for the patient, there is minimal risk to patients and staff at the facility, according to the hospital.
If confirmed, the new case would mark the first known instance of human-to-human transmission of the virus among the general public in the United States—something health officials warned would likely happen at some point.
Dr. Nancy Messonnier, director of the CDC’s National Center for Immunization and Respiratory Diseases, said earlier this week that it was “not so much a question of if this will happen anymore, but rather more a question of exactly when this will happen and how many people in this country will have severe illness.”
The authorities in California said that despite the announcement, “the health risk from novel coronavirus to the general public remains low at this time.”
“While COVID-19 has a high transmission rate, it has a low mortality rate,” the department said in the statement. “From the international data we have, of those who have tested positive for COVID-19, approximately 80 percent do not exhibit symptoms that would require hospitalization.
“California is carefully assessing the situation as it evolves,” it added.
The case marks the 60th in the United States, including 42 who returned from the Diamond Princess cruise ship that remains held off the coast of Yokohama, Japan, and three who were evacuated from Wuhan—the epicenter of the virus in China.
The CDC’s statement comes after President Donald Trump named Vice President Mike Pence as the leader of the coronavirus task force. He said: “Whatever happens. we’re totally prepared. We are ready, willing, and able.”
— Donald J. Trump (@realDonaldTrump) February 27, 2020
Pence will now be working with Health and Human Services Secretary Alex Azar in an “all-of-government” effort to coordinate the administration’s coronavirus response.
When asked about updates on a possible vaccine, Trump responded, “The vaccine is coming along well, and we think this is something that we can do fairly quickly.
“Of the 15 people [to have contracted the virus] … eight of them have returned to their homes, to stay at their homes until they’re fully recovered. One is in the hospital. And five have fully recovered. And one we think is in pretty good shape,” he added.