September 23, 2020

Then wildfires smoldering across the Cascade and Coastal mountain ranges rushed toward the Willamette Valley, forcing thousands to flee their homes and to take refuge in shelters and with friends. Thick smoke poured into the Portland Metro area, shuttering clinic, hospital and drive-through COVID-19  testing sites. The state lab closed, tabling specimens already collected and waiting for analysis. 

The unexpected mass movement of people and drop in access to testing, coupled with delayed data that would likely show a bump in cases from Labor Day weekend gatherings, paints a uncertain picture of COVID-19 in Multnomah County, public health officials told the Board of Commissions Tuesday in a briefing on COVID-19.

Record-shattering air pollution caused a jump in emergency department visits for people reporting respiratory symptoms. More people sought refills for asthma-related medications. Families welcoming evacuees were advised to do their best to keep space separate, wear masks and wash their hands. Homeless service providers opened cleaner air shelters and handed out masks. People were advised to stay home (again), close their doors and windows and use an air purifier or other air filtration device. 

“We’re already concerned about those most vulnerable groups, and the wildfire smoke just really exacerbated that,” Public Health Director Rachael Banks told the Board. 

“We saw more of a burden for those with health issues and economic issues such as the inability to afford an air purifier and access to housing,” she said. “Folks needing to be out in the air for longer, whether that’s to wait for the bus or run errands, and be exposed more to that air.”

Multnomah County had not met the state’s metrics for Phase Two reopening before the wildfires took off. Now the metrics, while still trending the right direction, are unreliable at best. It will be another month at least before the region has reliable data, before it can trust the trend.

“Clearly we hope it’s truly trending this way,” Banks said.

Metrics with a side of caveat

Communicable disease Director Kim Toevs gave a brief update on some of those key metrics: including case counts, and the rates of testing, cases and positivity.

Case Counts: This is the weekly number of cases used to form the “epi curve”, Toevs explained, pointing to a slide that has become as familiar as a face coverings in recent months.

“If you look at the very last column it looks very low, as if we have found a cure,” Toevs said. “That is not true.” That last column is the incomplete data from the current week, but the curve clearly shows a drop in cases beginning the first week in August.

“We have questions about how robust our data is because of the smoke,” Toevs said. “Even with that, we do have a trend as far as we can tell. We’re holding our breath to see what comes out of Labor Day and movement of people because of the region's evacuations.”

Testing: In recent weeks, fewer people have been tested for COVID-19. That’s in part due to testing sites shuttered due to smoke, and in part because people with mild respiratory symptoms might have assumed they were suffering from smoke, and not sought out testing for COVID-19. But a decline in testing also happens when a disease spread slows, and people are less likely to fear they are at risk.

The County continues to work with partner organizations on culturally-specific testing. Public Health has partnered with Hacienda Community Development Corp and the nonprofit, Verde, to host a COVID-19 testing day in the Cully neighborhood to address local disease spread. After twice being canceled due to smoke, the event is now scheduled for Oct. 3. 

The County is also supporting Latino Network and the Oregon Latino Health Coalition, nonprofits that are partnering with Legacy Health to host a Latinx-specific testing day. And it’s finalized a partnership with Latino Network to stand up a second regular drive-through testing site, this one in the Rockwood neighborhood.

Percent positive: The percent of tests that return positive results. This is one of two key metrics the state is using to determine when to reopen schools and the state, the Tri-County region and the county must all be below 5 percent. According to state data, the percent positive has declined over time, but we’re not there yet.

“Depending on how you calculate that, we’re either a bit below or right at that level now,” Toevs said. “ That seems to be an indication that we’re trending in the right direction. But that data will probably tell us less next couple weeks due to recent lack of testing access.” 

Case rate: Unlike the total count of cases, this is the count of cases per 100,000 people. This is the other key metric the state is using to determine when to reopen schools. A county’s rate must drop below 10 per 100,000 before all students can return to class. There’s an exception for young kids, who may be able to go back to school when the case rate drops to 30 per 100,000.

Neither Multnomah, Clackamas or Washington counties  are anywhere close to the 10 per 100,000 threshold that would allow all students to return to class. For the first time in the pandemic, though, the counties are nearing the 30 per 100,000 mark. 

But, Toevs cautioned again that wildfires have weakened the reliability of the most recent data, and it will be weeks before a trustworthy trend develops.

“All of us want to be in position of reopening, but we want a trend we feel confident in,” she said. “We’re getting there but we’re not there yet.”