science environment

Here's How Oregon's Reopening Depends On Testing And Tracing Benchmarks

By Jes Burns (OPB) and Erin Ross (OPB)
May 14, 2020 1 p.m.

Bradley W. Parks / OPB


Oregon is preparing to turn a corner Friday in its efforts to manage the spread of COVID-19. The state is expected to begin what will be a tiered reopening of restaurants, businesses and other public and private institutions around the state. Gov. Kate Brown introduced guidelines for the first phase of reopening last week.

Brown and her advisers may be feeling the pressure to reopen from customer-deprived businesses, tourist-hungry recreation communities and cooped-up residents, but the governor maintains the decision hinges on public-health-based, science-informed benchmarks.

“We have consulted extensively with doctors, nurses and public health experts. They tell us that under the right restrictions, we can take this step safely,” Brown said in a press conference.

The state has established a list of requirements that counties must meet to be cleared to enter the first phase of reopening.

“These thresholds will help counties keep people as safe as possible while we rebuild,” Brown said.

The prerequisites focus on the prevalence, detection and tracking of COVID-19 cases, as well as the health care system's capacity to handle additional cases that are likely to increase once Oregon starts relaxing some social-distancing measures.

If counties are able to prove they meet these requirements, then the Oregon Health Authority will allow them to begin reopening Friday.

“I think it's safe to assume that the majority of Oregon counties will be in a place … to be able to successfully reopen,” said OHA director Patrick Allen.

As of Wednesday, applications to reopen for 33 of 36 total Oregon counties were being reviewed by the Oregon Health Authority.

How close are we?

In the absence of a vaccine, Oregon is relying on two cornerstones to fight the novel coronavirus: widespread testing and a practice called "contact tracing," which is used to identify those who have come in contact with newly infected people. These two pieces figure prominently in the state’s prerequisites for reopening.

OHA is requiring that counties have the capacity to test 30 people per week for every 10,000 residents. For a high-population area like Multnomah County, that would equate to more than 2,430 tests per week.

An analysis by OPB found that during a recent week in May, 21 Oregon counties were already testing at a higher rate than is required — a positive indication that the capacity is there. OHA's statewide outlook for overall testing capacity is positive.

“I think it will be demonstrated that the amount of hospital and state lab capacity is sufficient, and we’ve got an ample reserve of other testing. And we can see that with the increase in the actual tests completed,” Allen said.

According to OHA, Oregon had the capacity to test more than 22,000 specimens per week at the state lab and major hospitals as of May 10. This equates to roughly to 52 tests per week for every 10,000 people in the state. It's well above the prerequisite amount, assuming counties can offer sufficient local testing locations and navigate the logistics of getting the samples to the appropriate test-processing facilities.

Is it enough?

Oregon’s prerequisite target of 30 weekly tests per 10,000 people was not pulled randomly from the ether. It’s based on the number of people currently infected with COVID-19 and how many others with whom those people are expected to come in contact.

Because the state is not able to test every Oregonian for COVID-19 on a regular basis, health officials use disease projections, or models, to estimate how many cases there are. These projections include carriers of the novel coronavirus who are asymptomatic or haven’t been tested.

The state’s model estimates there are 350 new infections each day and that each of those individuals has the potential to pass it to five additional people, all of whom will need to be tested.

Above and beyond this, the state estimated the need for a supply of extra tests to use in special cases, like outbreak situations.

These testing-need estimates assume that the number of new cases in the state will remain flat through the middle of June.

“If we can maintain a 60% reduction in transmission, that 15,000 or so tests per week would probably get us through what we need,” State Epidemiologist Dr. Dean Sidelinger said.

Maintaining that transmission-reduction rate as the state allows counties to reopen businesses and ease restrictions on public gatherings could prove challenging.

“As things open up, we expect people to have more contact with other individuals. Based on that increased contact, we would anticipate more infections. And based on more infections, we would anticipate people needing hospitalization and maybe even death,” he said.

Sidelinger said he doesn’t anticipate OHA bumping those county requirements up if the infection rate increases, but he does anticipate needing more tests overall.

Other organizations have put the number of tests Oregon should be conducting higher. An analysis from Harvard researchers and STAT News worked backward from the projected COVID-19 death rate for each state. They found Oregon should be administering 42 tests per week per 10,000 population.

The White House, on the other hand, made a blanket statement in mid-April that all states should be testing at a much higher rate still. For Oregon, that would translate to 70 tests per week for the same population level.

With such a wide swath of testing recommendations out there, public health officials are using a metric called the “test-positivity rate” as a backstop of sorts to determine if they’re testing enough.  This measure is a simple one: What percentage of tests is coming back positive?

“You know you’re missing a lot of cases if 80[%] or 90% of the people you test are positive,” said Dr. Michael Ryan, director of the World Health Organization’s Health Emergencies Programme, in an international briefing last month.



The reason goes back to the knowledge that there are more cases of COVID-19 than are being detected through testing — likely significantly more.

“We would certainly like to see countries testing at the level of 10 negative tests to one positive, as a general benchmark of a system that’s doing enough testing to pick up all cases,” Ryan said.

South Korea — the shining international star in the COVID-19 testing realm — has a test-positivity rate of 1.6%. The United States as a whole has not performed nearly as well, with a rate over 14%.

For Oregon, the metric gives us some good news. The state’s pandemic-long test-positivity rate as of May 12 is 4.1%. In recent weeks that’s dropped even lower; looking at tests returned May 6-12, that rate had fallen to 3.1%. This indicates the state is doing enough testing to have a reasonably good chance of detecting enough infections to control the outbreak.


OHA’s Allen says the agency will continue monitoring the test-positivity rate going forward.

“What we will be doing as we reopen is we’ll be watching it in the other direction. If the number of tests is more or less the same, if the rate is going up, that’s probably a pretty good indicator that we’re seeing more disease in the community,” he said.

The state is giving itself at least 21 days after the first phase of reopening to monitor disease spread before relaxing closures further.

Disease detectives on the ground

Along with testing, contact tracing is the mainstay of any infectious disease response. It’s not enough to quarantine someone who tests positive — you also need to isolate the people with whom they’ve come into contact and figure out who got them sick in the first place. It’s a time-intensive process, Sidelinger said. Contact tracers need detailed lists of everywhere the confirmed case has been. Then, they need to reach out to anyone who may have also been in that place. It’s a lot of time spent on the phone.

In order to reopen, counties will need to have a plan in place to hire the number of contact tracers necessary, train them and provide people with the resources they’ll need to quarantine safely.

“In order to reopen, [counties] don’t need to have everyone on board, but they’ll need to have a plan for how they’re going to get there,” Sidelinger said.



Based on the current six-week model projection, OHA says Oregon needs to hire at least 600 new contact tracers across the state. Each county needs to have a minimum of 15 contact tracers per 100,000 people in order to open. It’s the responsibility of the counties, and not OHA, to find them, Allen said.

“It’ll be a mix of, potentially, county employees and local community health care workers,” Allen said.

If a county doesn’t have the funds to hire the contact tracers, OHA will cover the costs, using money from the CARES Act, the coronavirus-focused economic rescue legislation passed by Congress in March. But the county will still need to recruit the contact tracers, regardless of who is footing the bill.

“They’ll have contacts with local organizations that have deep and strong relationships with communities at risk,” Allen said.

Of course, many counties in Oregon have relatively small populations. Places like Lake County only need to have one or two contact tracers to do the job. But even counties with low populations can have large outbreaks, especially if residents’ work — like agricultural labor or meat processing — doesn't allow for social distancing. Other counties might have large populations of farmworkers and undocumented immigrants who could have specific needs.

As OHA reviews plans for reopening, the agency isn’t just looking at the total number of contact tracers in each county. Counties' plans will need to outline any additional steps that will be taken to help those communities — including finding additional contact tracers who are fluent in more than one language.

“We would imagine that a county, even if they were small, know that they have a large farmworker population that speaks Spanish, and if they have another population that spoke a different language, they would need to identify individuals or organizations in the community that they could partner with,” Sidelinger said.

Allen said his agency is encouraging counties to reach out to community health workers to take on contact tracing work.

“We want people who have some background in health, but are culturally and linguistically appropriate for the community,” he said.

And if they don’t have the health care background, that can be OK, too, Allen said. “It’s hard to train someone to be responsive to the needs of a community. But we can train specifics about contact tracing, what types of questions you need to ask.”

Ultimately, the county numbers are just goals, Sidelinger explained. As restrictions ease and COVID-19 transmission rises, there will be more cases to trace. Counties need to be ready to hire more people, should they need it.

If a county has an outbreak beyond what their contact tracers are able to handle, OHA has identified more than 100 current employees who can be re-deployed to help those areas.

“We’re already sending people to Marion County, where they’re having some outbreaks,” Allen said.

Like the county numbers, 100 OHA-deployed contact tracers is just a starting point. If they need more, they’re prepared to bring more on board.

Information gathered by contact tracers across the state will be shared in the same, central data bank.

Stopping the spread

Even though counties need to hire and train hundreds of contact tracers, that may not be the most challenging part of a county’s containment strategy, Allen said. “The main thing that needs to be done, in addition to hiring contact tracers, is facilitating effective quarantine and isolation.”

Contact tracing and testing only works if the infected people stay home to keep others safe. People who are sick will be asked to quarantine themselves — not just from the outside world, but from family members, too.

All told, Allen says getting people to isolate and connecting them with resources will be one of the hardest parts of re-opening.

“It’s not just the whole number of staff, you’ve actually got to have a strategy. As I’ve been going through these applications, some of them are really good about thinking about and articulating a holistic strategy. Others, less than,” Allen said, adding that OHA will work with those counties to help them flesh out their plans.

Figuring out the isolation piece can be incredibly difficult.

“If you ask someone to isolate, and if they live with family in a small house, or need to work to put food on the table, that’s basically given them an impossible job,” Allen said. Especially if someone hasn’t been diagnosed with the coronavirus yet, but had contact with an expected case.

Bradley W. Parks / OPB

Counties will need to account for this in their applications to reopen. Some might work to house people in empty hotels or apartment buildings. Others will focus on connecting the infected with financial aid, or SNAP nutrition benefits. Others will need help with child care.

Undocumented workers and farmworkers, in particular, could need more assistance. They might not have the necessary records to qualify for traditional safety nets like SNAP benefits, paid sick leave and income replacement.

Education will be a big part of counties’ plans, too.

Oregonians have been locked down for a long time. It’s reduced the spread of cases, but people are ready to leave their homes.

“I think that’s what we’re going to struggle with. Having this group of contact tracers who are going to have to work with people who are very anxious to get out into the community,” Sidelinger said. The contact tracers can help facilitate that.

“As knowledge of a case comes in, you need to call the top contacts and say to stay home for seven to 10 days,” he added.

But those people might not show any symptoms and, in fact, may not be infected. Convincing them to stay home is going to be a hard sell, so counties will need to do outreach to convince people that isolating is necessary to keep themselves, their family and their community safe.

It's a big task for counties, Sidelinger said.

“They’ll need to call them and say, Hey, what do you need to stay home?" he said. "How can I help you? What’s important?”