OHA Study: 1% of Oregons have evidence in blood of past COVID-19 infections

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Rate is 10 times higher than traditional test show

PORTLAND, OR (KTVZ)-As of mid-June, 1% of Oregon without COVID-19 had evidence of past virus infection in their blood and had 10% of infection rates obtained in conventional studies. If it is twice as expensive, you can go to new research.

The Oregon Department of Health epidemiologist who wrote the study appeared on Friday at the Centers for Disease Control and Prevention. Weekly Morbidity and Mortality Report (MMWR)Found that nine of 897 blood samples collected from 19 healthcare facilities around Oregon between May 11 and June 15 contained antibodies to the virus that causes COVID-19. Was

The study also suggests that the infection rate increased with age and that no antibody was detected in the blood of pediatric patients under 17 years of age. The proportion of patients aged 18-64 was 0.4-0.5%. 1.6-2.1% for those over 65 years old.

The results show that a “substantial” proportion of the population of Oregon shows an undiagnosed and unreported infection from COVID-19.

Paul Cieslak, MD, MD, co-author of studies on epidemics and vaccination, and OHA’s Medical Director, said, “We suspect that much more segments of the Oregon population are exposed to COVID-19 and are infected. “. “But these results show that the majority of Oregon people are still infected with this virus.”

The first case of COVID-19 in Oregon was diagnosed on February 28. By May 31, COVID-19 was positive in 4,243 people in Oregon, or in 1 in 1,000.

We think this rate is lower than the actual number of infections in the state, as this rate does not take into account those who have been infected but did not seek testing (eg, those who are mild or asymptomatic, or who do not have access to testing) It is being done.

Such a seroprevalence survey-testing blood samples for antibodies-researches all those who have been previously infected with COVID-19, including those who have or have not shown symptoms. By identifying, the infection rate can be estimated more accurately than conventional tests. Seek care.

“Most of us are still vulnerable, so we need to continue our physical distance and masking exercises until we have effective vaccines, treatments, or other means to reduce the disease.”

Antibody tests have shown that people who were tested for antibodies, even if they had no symptoms, were at some point exposed to COVID-19.

However, if you suspect you have COVID-19, Cieslak stressed that getting it is not a good test, because the antibody does not appear in the blood until 2-3 weeks after being exposed to the virus. ..

In addition, he said, “I don’t know if antibodies to COVID-19 mean that you are protected. So you need to wear a face cover, keep a physical distance, and keep your hands washed. “

NewsChannel 21 asked Cieslak if he could feel more at ease with the increased proportion of Oregons with antibodies in their blood.

“It would have been great if we could find 50 percent of the population infected,” he said. “That is, first of all, the virus is far less likely to be scared, as symptoms will occur because the proportion of people who are infected is much smaller. I don’t know that means having.”

By comparison, he points out that New York City conducted a similar study and found that 20% of the cities were infected, based on the antibodies present in their blood.

He said research confirms Oregon is more successful in fighting the virus than most states. He couldn’t say for sure-due to the proper social distance or the face mask-a bit lucky.

Cieslak said the effort wasn’t intended for a one-time study, so he hopes to update the exposure results in the near future.

For more information on antibody testing, please visit the CDC website. https://www.cdc.gov/coronavirus/2019-ncov/testing/serology-overview.html..