From China to Sea-Tac to Shoreline: Here’s how screening for coronavirus works

A traveler arrives at Seattle-Tacoma International Airport after a 12-hour flight and files off the airplane with other passengers into the airport’s international terminal, or S gates.

After a long wait in line, she eventually takes her turn at a passport-control kiosk, where a U.S. Customs and Border Protection agent checks travel documents.

If she recently visited mainland China, the agent flags her as a medium risk and she’s ushered to a nearby waiting area outside a federally run airport clinic called the Division of Global Migration Quarantine (DGMQ).

There, U.S. Centers for Disease Control and Prevention (CDC) medical staff further survey her about her travels and health:

Did you visit the city of Wuhan or the Hubei province?

Do you have a cough? A runny nose? A fever?

No, she responds to each question.

After the CDC staffers take her temperature and run a few other health checks, they determine the traveler has no symptoms and send her on her way — but with a few instructions: For up to the next two weeks, they advise her, she should stay home, keep away from others and take her temperature at least twice each day. If the traveler develops a fever, a cough or other symptoms, she should contact her public health department for further advice before seeking care.

This hypothetical example demonstrates the most likely of three general outcomes for travelers arriving at Sea-Tac who have been flagged during the screening process for the novel coronavirus, a respiratory illness first identified in Wuhan, the capital city of Hubei province in central China. As of this week, the novel coronavirus outbreak that started there has killed more than 2,130 and infected more than 75,000 people worldwide, mostly in China.

The two other screening outcomes, both of which deem travelers as “high risk” for the virus — involve travelers who’ve recently been to mainland China and now have flu-like symptoms, or those who show no signs of illness but who’ve traveled in Wuhan or Hubei province.

As of this week, public health officials had encountered only one person who met such high-risk criteria during scores of screenings at Sea-Tac, according to Dr. Scott Lindquist, state epidemiologist for communicable diseases with Washington state’s Department of Health.

That person, who has no symptoms but is considered a “close contact” of someone confirmed with coronavirus, is self-quarantined, according to the state health department.

Medium risk most likely

COVID-19, as the viral illness is officially called, is part of a large family of viruses, some of which can be passed from animals to people, though public health officials have yet to pinpoint the source of the latest strain.

The new coronavirus can start with mild symptoms, including a runny nose, a sore throat, a cough or a fever, and later lead to pneumonia or breathing problems. In rare cases and with certain vulnerable patients — the elderly or those with preexisting conditions, such as diabetes or heart disease — new coronavirus can be fatal.

The ongoing outbreak remains largely centered on the city of Wuhan, but it has infected people in at least 29 nations, including the United States. Public health officials in this country have since put in place a multilayered response that incorporates federal, state and local resources.

Since Jan. 21, after a Snohomish County man who had traveled alone to Wuhan became the first person in the U.S. diagnosed with coronavirus, the CDC has confirmed 14 more cases in six other states. The man in his 30s didn’t fly directly from Wuhan to Sea-Tac. When he arrived there on Jan. 15, he had no symptoms. He went to a doctor four days later after coming down with a cough and fever, officials have said.

“There will likely be additional cases in the coming days and weeks, including among other people who returned from Wuhan,” the CDC said in a recent statement.

The U.S. declared a public health emergency on Jan. 31, barring foreign nationals who recently traveled in mainland China from entering the country, and placing 195 Americans evacuated from Hubei under quarantine at a California military base.

The Department of Homeland Security has since directed all American flights from China or travelers who’ve recently visited that country to be routed through one of 11 designated U.S. airports with quarantine facilities and screening procedures.

The screening process, among America’s first lines of defense against an outbreak, has been repeated over and over again at Sea-Tac and the 10 other airports designated to handle incoming Americans who might have been exposed. Each of the airports has a DGMQ quarantine facility that’s staffed around the clock with CDC personnel and has established enhanced screening procedures.

As of Wednesday, the CDC estimated about 40,000 people had been screened at airports nationwide, though the agency couldn’t readily provide a breakdown for how many of those occurred at Sea-Tac. The number of screenings has steadily dropped, as flights from China to the U.S. have been canceled, said CDC spokesman Scott Pauley.

“But people are still being screened at airports,” Pauley said. “They may not necessarily be coming in on direct flights from China, but they’ve traveled there within the past 14 days. So if someone left China a week ago, then went to Japan and then flew to the United States, they should be screened.”

At Sea-Tac, Delta and Hainan, the two airlines operating flights from China at this time of year, canceled all flights from that country on Feb. 2, airport spokesman Perry Cooper said. Until their cancellation, the two flights had brought an average of 670 passengers to Sea-Tac per day, Cooper said.

The hypothetical scenario of the asymptomatic traveler deemed a “medium risk” for having traveled in China, but not in Wuhan, represents by far the most likely of three outcomes for those who’ve gone through the screening process at Sea-Tac, Lindquist said.

As of Wednesday, state public health officials have deemed 779 people in this general category, or as under “public health supervision.” Most of these individuals were flagged during the airport screening process, the health agency said, though the group also includes a few others who came into contact with the lone man in Washington to be confirmed as infected with the new coronavirus.

The other two airport screening outcomes involve travelers flagged as “high risk,” though so far only the one traveler has met such criteria at Sea-Tac, Lindquist said.

What about high risk?

The first “high risk” outcome would involve someone who had been in China and has symptoms — say, a fever or cough.

“They would get pulled out right away and put in an (DGMQ) isolation room,” Lindquist said.

State or local public-health officials would pick up the sick person and take them from the airport to one of four hospitals designated and equipped to receive patients who have potentially been exposed. Medical staff at these hospitals — Harborview, Virginia Mason and Seattle Children’s hospital in Seattle, and EvergreenHealth Medical Center in Kirkland — would isolate the patient, conduct further evaluations and determine whether to admit him or her under quarantine, Lindquist said.

The third screening outcome, also deemed high risk, involves travelers without symptoms but who’ve traveled in Wuhan or Hubei province or come into close contact with someone with coronavirus. Public-health officials have identified one traveler in this category — an unidentified person who came into contact with another person confirmed to have the virus.

Travelers in this group face being placed under quarantine and could be sent to the designated isolation facility in Shoreline, Lindquist said. Any designated quarantine facilities must meet a list of CDC requirements, including providing access to Wi-Fi, Lindquist said.

“But to be frank, right now we have not had to place anyone in these facilities,” he added.

The Washington State Patrol Fire Training Academy in North Bend, which officials at one time had designated as a quarantine site, is no longer going to be used for quarantines due to logistical and proximity reasons, a DOH spokeswoman said Wednesday.

Travelers put under quarantine would require active monitoring by public health officials for up to 14 days — the incubation period for the virus. Monitoring involves taking temperatures twice a day and contact with a public-health official at least once a day.

On a case-by-case basis, health officials would decide whether to allow travelers facing quarantine to do so in their own homes should their living arrangements support it, Lindquist said. The only “high risk” traveler so far screened at Sea-Tac was allowed to “self-quarantine,” the DOH said.

“We might ask them, ‘Where do you live?’ And if it’s … just me and my dog in an apartment, well OK — can you quarantine yourself for the next 14 days?” Lindquist said. “Then that’s possible. But it also could be someone who lives with a family, it really just depends if they’re able to stay away from others who live with them.”

Such at-home, “voluntary” quarantines would require that officials “actively monitor them mostly over Skype or through texts,” Lindquist said. Public health officials “would take care of getting their groceries or anything else they would need to stay in place for 14 days,” he said.