New research on the coronavirus cases in Washington state suggests that the virus may have been spreading through the area for about six weeks, the New York Times reported. This means that between 150 and 1,500 people could be infected with the disease, officially known as COVID-19.
To arrive at that conclusion, two state researchers analyzed the genomes of two coronavirus infections. This included the genome of the state’s first known case, which was announced by the Centers for Disease Control and Prevention (CDC) on Jan. 20. The unique circumstances and the genetic similarities of both cases led the researchers — Dr. Trevor Bedford of the University of Washington and Dr. Mike Famulare of the Institute for Disease Modeling — to determine that the virus may have been spreading through the community for weeks.
According to the Times, although the two infected people live in the same county, they did not come into contact with each other. In addition, the second case occurred after the first patient would no longer be considered contagious. Nonetheless, in both cases the virus contained a rare genetic variation, which researchers say indicates that it is likely that they are related.
Famulare said that if the virus has been spreading undetected in Washington state since mid-January, when the first victim was announced, it could mean that between 150 to 1,500 have it. The researcher said that the most likely estimate was between 300 to 500 people.
Per the Times, Famulare said that the people “have either been infected and recovered, or are currently infected now.”
He added that most of the people would now be in the early stags of incubating the virus and might not be contagious yet. However, Famulare said his figures were a “best guess, with broad uncertainty.” Both scientists have submitted their findings to state and federal health officials.
Washington State Department of Health officials told the Times that they would know more about whether the virus had been circulating once they analyzed the genetic sequences from the state’s other cases. The state expects to obtain that information soon.
On Sunday, the U.S. recorded its second death from coronavirus in Washington state. The victim was a man in his 70s with underlying health conditions. He died at the EvergreenHealth hospital in Kirkland, Washington, the same hospital where the first coronavirus victim died on Saturday.
Officials also announced three confirmed coronavirus cases at EvergreenHealth. All were elderly patients in their 70s, 80s and 90s with underlying health issues. They are in critical condition.
According to the World Health Organization, there were 62 confirmed cases of coronavirus in the U.S. as of Sunday.
Gizmodo has reached out to the researchers that conducted the study on the coronavirus cases in Washington State. We’ll update this story if we hear back.