



(Graphics courtesy of Oregon Health Authority)
WIDESPREAD INFECTION. Preliminary results from random door-to-door
TRACE-COVID-19 sampling by Oregon State University last month suggest 17% of
the Hermiston community have had the novel coronavirus that causes COVID-19.
The study, known as Team-based Rapid Assessment of Community-Level
Coronavirus Epidemics (TRACE-COVID-19), canvassed 30 neighborhoods. The
field workers (pictured) received samples from 471 people, and 41 tested
positive for SARS-CoV-2, the virus that causes COVID-19. (Photos courtesy of
Oregon State University)
From The Asian Reporter, V30, #09 (August 3, 2020), pages 13 & 16.
OSU TRACE-COVID-19 results suggest 17% of Hermiston
community infected with SARS-CoV-2
HERMISTON, Oregon — Preliminary results from random door-to-door
TRACE-COVID-19 sampling by Oregon State University (OSU) late last month
suggest 17% of the Hermiston community have had the novel coronavirus that
causes COVID-19.
The study, known as Team-based Rapid Assessment of Community-Level
Corona- virus Epidemics (TRACE-COVID-19), initially began in late April in
Corvallis. The random sampling effort was also expanded in late May to
include 30 neighborhoods in Bend, Oregon, as well as Newport, Oregon, in mid
July.
"The results of this study are a significant warning," said Hermiston
mayor David Drotzmann. "We now have a clearer picture of how many people are
carrying this disease without knowing it, and how rapidly it is spreading
family to family, household to household."
"Our results indicate the virus is extremely widespread in Hermiston and
more prevalent than previous data had indicated," added Ben Dalziel,
assistant professor in the College of Science at OSU and co-director of the
project.
In Hermiston, 29 two-person field teams canvassed 30 neighborhoods, with
249 of the households visited, or 44%, agreeing to participate. In all, the
field workers received samples from 471 people, and 41 tested positive for
SARS-CoV-2, the virus that causes COVID-19.
TRACE modelling, which takes into account the sensitivity of the test and
the locations of the positive individuals, estimates the prevalence of the
virus was 169 out of every 1,000 people in Hermiston. That translates to
nearly 3,000 infected people in the city overall.
"This study confirms what we have feared based on weeks of troubling data
from the Oregon Health Authority: The coronavirus has spread throughout
Hermiston and threatens the entire community," said Oregon governor Kate
Brown. "Umatilla County is now in a ‘baseline, stay home’ status and we must
do everything possible to contain these outbreaks. Wear your face coverings,
watch your distance, and wash your hands. I’d like to thank the TRACE team
at Oregon State for their hard work on this important research."
In announcing prevalence results, the TRACE team follows reporting
policies used by the Oregon Health Authority and local health departments.
"These data reaffirm what we learn from public health investigations,
that in addition to outbreaks, there are many cases of COVID-19 which are
sporadic," said Dean Sidelinger, health officer and state epidemiologist at
the Oregon Health Authority. "This indicates wide community spread."
Oregon State University researchers also gathered multiple wastewater
samples from Hermiston and neighboring Boardman in early July and again from
July 21 to 24. Analysis of the wastewater samples "showed consistently
strong viral signals in both cities that have remained very high and not
decreased over time," said lead researcher Tyler Radniecki of the OSU
College of Engineering.
"The levels recorded are significantly higher than any of TRACE’s
previous wastewater samples," he added.
Both the door-to-door and the wastewater results indicate the virus is
widespread in Hermiston and the situation is serious and warrants immediate
action, said TRACE leaders.
"Half of the 30 randomly selected neighborhoods we visited had at least
one positive participant," said Dalziel. "This means that the virus is very
widespread within the community, not clustered in only a few locations."
As well, 80% of those Hermiston community members who tested positive in
the TRACE sampling did not report symptoms of the virus.
"This result is cause for concern because efforts to monitor and stop
spread that are based on symptoms will miss many infected individuals," said
Dalziel. "The large number of infected people without symptoms combined with
the widespread distribution of the virus within Hermiston creates
significant risks for the entire population."
"Residents should pay close attention to social distancing and follow the
statewide face-covering mandate that began [in July]," added Javier Nieto,
dean of OSU’s College of Public Health and Human Services and another of
TRACE’s leaders. "Other measures, such as avoiding large gatherings, will
also help slow the spread of the virus, in line with the state of Oregon’s
recent decision to move Umatilla and Morrow counties back to phase one
COVID-19 status. It is particularly important that individuals who have
symptoms or who have tested positive follow state and county health
guidelines such as self-isolating and seeking medical care."
Hermiston is the largest city in northeastern Oregon at just over 18,000
people, and Umatilla County ranks first among the state’s 36 counties in the
number of COVID-19 cases per 10,000 people, with more than 222 cases per
10,000 as of July 30. This tally includes both current and past cases. Most
of the businesses where cases have spiked are in the food processing
industry, though the list also includes Hermiston’s Walmart distribution
center and Marlette Homes, a maker of manufactured houses.
The TRACE study is a collaboration of the OSU colleges of Science,
Agricultural Sciences, Engineering, Public Health, and Human Sciences, and
the Carlson College of Veterinary Medicine, in partnership with county
health officials.
"We are grateful to the Hermiston residents who were willing to
participate in TRACE," said Jeff Bethel, an associate professor in OSU’s
College of Public Health and Human Sciences and a member of the TRACE
leadership team. "The results show that if individuals wish to avoid
infection, they need to be extra vigilant and abide by health officials’
guidance. And because the vast majority of people infected report no
symptoms, extra care and additional testing is warranted beyond only those
who report symptoms."
TRACE uses a statistical model to estimate the proportion of the
community that is infected during the period when the samples were
collected. The model uses information on the number of samples, the number
of positive tests, the sensitivity of the tests, and the locations of the
positive results within neighborhoods and households.
"TRACE does two things," Dalziel said. "First, we find and get help to
participants who are infected but do not know they are, which reduces the
chances of these folks unknowingly spreading the virus to other people.
Second, we rapidly estimate how widespread the virus is in the general
population, which informs public health strategies. Rapid, representative
estimates of community prevalence provide a different type of information
than case counts or hospitalizations, since those indicators tend to lag
behind current conditions, and are biased toward individuals who show
symptoms."
The study initially was funded by OSU and a grant from the David and
Lucile Packard Foundation, and has been aided by work from the OSU
Foundation and the OSU Alumni Association. Funding from PacificSource Health
Plans allowed for expansion to Bend and Newport and additional sampling in
Corvallis, and the Oregon Health Authority funded the Hermiston sampling.
At each home visited by TRACE field workers, members of the household are
invited to participate in the study. Those who choose to take part are asked
to provide information such as their name and date of birth; to fill out a
simple consent form; and to answer a few confidential, health-related
questions.
Participants are given a nasal-swab test kit that they administer to
themselves inside their home and their minor children if they want them to
take part. The field staff wait outside, and the participants leave the
completed test kits outside their front door. Field staff maintain a safe
distance at all times and do not enter anyone’s home.
The tests used in TRACE-COVID-19 collect material from the entrance of
the nose and are more comfortable and less invasive than the tests that
collect secretions from the throat and the back of the nose.
The field workers leave participants with information about the project
and how they will receive their results as well as health guidance from
county health officials and the Centers for Disease Control and Prevention.
Participants in the study are sent their results and those of their minor
children by secure e-mail with receipt by standard mail delivery as a
backup. Everyone’s personal information is safeguarded.
The diagnostic testing component of TRACE operates through a partnership
between the Oregon Veterinary Diagnostic Laboratory, which is located at
OSU, and Willamette Valley Toxicology.
COVID-19, first reported to the World Health Organization on December 31,
2019, has been confirmed in more than 17 million people worldwide and has
killed more than 680,000 people. In the United States, there have been more
than 4.3 million reported cases — including more than 18,000 in Oregon — and
more than 150,000 deaths nationwide. Umatilla County has had 1,943 confirmed
cases and 23 deaths.
"TRACE’s work is only possible because community members and health
officials have worked with the TRACE team to obtain meaningful results that
present a representative picture of the whole community in a very short
period of time," Bethel said. "We’re grateful for their help in providing
information that is useful both to individual residents and to health
officials."
To learn more about the TRACE project, or to read frequently asked
questions, visit <https://trace.oregonstate.edu>.
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