SEATTLE — Several health agencies released their findings of the Seattle Flu study, finding "cryptic transmission" of the coronavirus in Washington state.
Trevor Bedford, a doctor at Fred Hutchinson Cancer Research Center, said the virus was likely in the state at least a week before the first person began showing symptoms.
The coronavirus has its own family tree, what scientists call phylogeny, and that is telling them a lot about what's happening.
Bedford said the virus jumped from an animal into its first human between mid-November and mid-December in Wuhan, China. It's been mutating into dozens of strains since then. The virus wasn't mutating a lot, but enough to allow the tracking of the genomes of individual cases, which is helping build the picture of how the virus has moved around the world.
Since the virus is so new, Bedford said in a presentation to the American Association for the Advancement of Science that all traces lead back to that one event in Wuhan.
Bedford has been tweeting about his research and among his findings are that the first and the second Washington coronavirus victims had "with near virtual certainty" the same strain.
Washington's first coronavirus victim traveled to China and was confirmed ill with the virus on Jan. 21. He traveled through the Seattle-Tacoma International Airport on Jan. 15. Researchers believe the virus began circulating on that date, several days before anyone even knew there was a case of coronavirus in the United States.
Washington's second case, a teen boy and student at Jackson High School in Mill Creek, did not travel and is considered infected through community transmission. The virus was confirmed in the second person on Feb. 28.
The victims are known by their state and victim number. WA1 is the first victim, WA2 the second. On Twitter Bedford wrote, "This case, WA2 is on a branch in the evolutionary tree that descends directly from WA1, the first reported case in the USA sampled on Jan 17., also from Snohomish County."
It can take several days following a test before the results are confirmed and reported out by health authorities.
Bedford has tracked the progress of other diseases as well, such as Ebola and SARS.
He tweeted that the state could see several hundred cases of coronavirus.
What are coronavirus symptoms?
The symptoms of coronavirus are similar to the flu or colds. Symptoms include a runny nose, headache, cough, sore throat, fever and a general feeling of being unwell, according to the Washington State Department of Health.
The severity of symptoms ranges significantly. Some cases are very mild with symptoms similar to the common cold, and some cases are more like severe pneumonia that require hospitalization. Most deaths have been reported in older adults who had other health conditions, according to DOH.
Symptoms may appear as soon as two days after being exposed to the coronavirus or as long as 14 days.