Page 28 - aruba today

A28 SCIENCE
Saturday 14 March 2020
Scientist links 2 state outbreaks with genetic fingerprints

By CARLA K. JOHNSON next day. On Jan. 19, he
AP Medical Writer visited a clinic in and was
SEATTLE (AP) — A U.S. scien- hospitalized on Jan. 20.
tist is helping public health "They did very aggressive
authorities understand and contact tracing looking to
track the coronavirus, turn- identify anybody who had
ing up clues about how it had contact with that ini-
arrived and spread through tial case and sort of con-
Washington state and be- centric circles outward," Dr.
yond, including potentially Nancy Messonnier of the
seeding an outbreak on Centers for Disease Con-
the Grand Princess cruise trol and Prevention said
ship. Wednesday. She called
Washington's gover- Bedford's work "an interest-
nor banned large public ing hypothesis," but said the
events in three counties outbreak could have been
on Wednesday, a strat- caused by "a secondary
egy guided by the work seeding."
of Trevor Bedford and his Kristian Andersen, a ge-
colleagues, who have es- netic epidemiologist at
timated there are currently Scripps Research in La Jol-
1,100 active cases in the la, California, agreed that
state, most of them undis- the virus was introduced to
covered by testing. Washington state by one
Like a detective studying In this Feb. 7, 2019 photo provided by the Fred Hutch News Service, Trevor Bedford, a computational person and suggested that
fingerprints, Bedford uses biologist at the Fred Hutchinson Cancer Research Center, poses at the center in Seattle. the active cases probably
the genetic code the virus Associated Press exceed 1,100. Neither of
leaves behind. The dots he outbreak on the Grand planation, Chiu said. A perhaps the 35-year-old the conclusions Bedford
connects are mutations in Princess cruise ship in Cali- cruise passenger or crew man who was the first described is a surprise, he
the genetic alphabet of the fornia. member was infected in known U.S. case. The coro- said in an email.
virus, a 30,000-letter string "They all are very similar another country, coinci- navirus infection rate in the "The United States has com-
that changes at the rate genetically," Bedford told dentally by a virus with Seattle Flu Study, a project pletely failed to prepare for
of one letter every 15 days. The Associated Press. "It the same mutations as the mapping seasonal flu, indi- the pandemic — despite
Those tiny mutations don't seems very possible" that Washington state cases. cates there could be 1,100 having adequate time
change the virus' effect on virus from the Washington "Common sense tells you active COVID-19 infec- — and we currently have
people, but they do allow outbreak made it onto the it more likely came from tions in the state, although one of the lowest capac-
scientists to draw conclu- Grand Princess. Washington," Chiu said. because of limitations in ity for COVID-19 testing,"
sions about how it spreads Dr. Charles Chiu at the Uni- For most people, the coro- the modeling that number he wrote. "This continues to
from person to person. Af- versity of California, San navirus causes only mild could range from as low as be an enormous problem
ter a person gets tested Francisco, agreed. He pro- or moderate symptoms, 210 to as high as 2,800 ac- and it is highly likely that we
for the virus with nasal and vided genome sequencing such as fever and cough. tive infections. are currently be missing the
throat swabs, a small bit of of seven samples from in- For some, especially older Health authorities tried to vast majority of cases oc-
the specimen can be used fected passengers who got adults and people with trace all the people who curring across the country."
to rapidly sequence the vi- off the Grand Princess this existing health problems, it had contact with the first "Unless our ability to detect
rus' genome. That work has week. An eighth sample can cause more severe ill- U.S. case, a resident of Sno- cases is transformed within
been happening, not just from an earlier Grand Prin- ness, including pneumonia. homish County, north of Se- days and aggressive strate-
in Seattle, but in other labs cess cruise to Mexico had The vast majority of people attle, who had visited Wu- gies for responses are put
around the world. Scientists ties to Washington state, recover within a few weeks. han, the Chinese city that in place, within a couple of
are sharing their results on Chiu said, and that per- Based on genome se- was the initial epicenter of weeks, we are going to find
a public platform where son likely seeded the out- quencing of 18 Washing- the outbreak. He landed ourselves in a situation that
they've been sharing influ- break among passengers ton state cases, Bedford at Seattle-Tacoma Inter- is very similar to the one
enza genome data since on board as the ship left for believes the state outbreak national Airport on Jan. 15 currently unfolding in Italy,"
2008. Hawaii. began with one person, and started feeling sick the Andersen wrote.q
This week, Bedford's lab "The simplest explanation,"
at the Fred Hutchinson Chiu said, is that the earlier
Cancer Research Center Grand Princess passenger
worked with California re- had been in Washington
searchers to find links be- state and then seeded the
tween a cluster of cases in cruise ship outbreak.
the Seattle area and the There's an alternative ex-