x
Breaking News
More () »

Portland's Leading Local News: Weather, Traffic, Sports and more | Portland, Oregon | KGW.com

Contact tracing picture grows fuzzy as COVID-19 cases swamp the system

Some days, as many as 80% of cases can not be traced to a known source.

PORTLAND, Oregon — With cases of COVID-19 skyrocketing in Oregon it’s important to know what the numbers are telling us.

First, you've probably heard about contact tracing. That's where workers contact people who are sick and try to figure out who infected, them among other things.

The numbers changed significantly near the end of October. According to the Oregon Health Authority (OHA), on Oct. 28, 35% of cases could not be traced to a known source. Just six days later that number jumped to 80% of cases that could not be traced to a known source.

Dr. Jennifer Vines, the Multnomah County Public Health Officer, said it's difficult with so many cases.

“We are still making those calls - we're triaging those calls and still very much doing the work. But we do start to get a more fuzzy picture rather than a higher resolution picture as those details just get harder to come by from the sheer volume of work,” Dr. Vines said.

And then, there is the case count. Each day OHA releases a new case count, they are a day behind. The numbers released Thursday are the positive cases gathered up from the day before, on Wednesday.

The Oregon Health Authority reports that from the time this all began back in March until the most recent week available -- which ended Nov. 7, a total of 51,155 people were reported as positive cases. That does not include Thursday’s record high.

Of those cases, 5% were presumptive positives, that’s 2,591 people. What’s that mean? It's people with COVID-19 like symptoms who had close contact with a confirmed case but no lab test to confirm they are positive.

Yes, they are counted in the daily positive numbers. Dr. Vines said researchers are careful not to inflate the numbers. If someone in an office tests positive for the virus, coworkers are only counted if they are showing symptoms. Those who spend at least 15 minutes within six feet of the infected person would be considered a contact and told to quarantine. Dr. Vines said it does not matter if they wore a mask during that time or not.