In an ideal scenario, contact tracing would mean widely testing a community, quickly identifying cases, and getting contagious individuals to isolate. Then, health officials would contact family members, coworkers and others who might have been exposed, to test and quarantine them before the virus spreads further.
Maricopa County Public Health started contact tracing with the region’s first reported COVID-19 cases in January. The department says older individuals who test positive, or anyone who lives in a communal setting, now receive a phone call from a live contact tracer. But the majority of new cases being reported are now among younger, lower-risk individuals and the county reaches out to them via text message.
In a news conference last week, Dr. Rebecca Sunenshine, the county’s medical director, acknowledged the system is far from perfect. She said 1 in every 5 positive cases reported to the county has no contact information.
“That causes a considerable delay," Sunenshine said. "Of that 20%, we’re only ever able to get 5% of that contact information.”
That means each day, hundreds of individuals known to be contagious in Maricopa County aren’t contacted. Neither are the people they may have spread the disease to. Of those who are contacted, the county says nearly 60% don’t respond.
When the county developed its contact tracing system, it was preparing for a scenario where they might deal with 500 new cases per day; lately, it’s been thousands. The county says more than 100 employees are working on contact tracing. The governor in mid-June also authorized the National Guard to help with these efforts.
But Sunenshine said the county relies on labs to report cases before contact tracers can reach out to anyone, and that’s a challenge, too. Sunenshine said the average wait time for test results in Maricopa County is four days. Sonora Quest Laboratories, which is processing the majority of the state’s tests, says its turnaround time is about a week.
“The longer it takes to report those labs to public health, the less effective the contact tracing that we can do is," Sunenshine said.
Critics say this is the major flaw in the state’s system. Will Humble is the former director of the Arizona Department of Health Services.
“Turnaround time is embarrassing," Humble said in an interview.
Humble said it’s unrealistic to expect people to isolate at home before they have confirmation that they’re infectious. If they’re waiting days for results, they’re likely to expose others in the meantime.
“The only way contact tracing works is if you have robust sampling and a really fast turnaround time," Humble said.
When the governor allowed the state to reopen in mid-May, Arizona ranked 49th among states in terms of the percentage of the population tested for the virus. Testing has increased, but Arizona still lags behind most other states, according to the Kaiser Family Foundation.
Arizona Congressman Greg Stanton said the state should not have reopened without an aggressive testing and contact tracing strategy in place.
“Their failure to properly prepare for the reopening during the relevant time period while we were closed is a disaster, a disgrace, and it’s costing lives," Stanton said.
Stanton said the state and the county both received funding through the CARES Act that could have been put toward testing and contact tracing that hasn’t been spent fast enough.
“This is not the time to put money into reserves. Resources should be used right now," Stanton said.
Humble agrees. And as he sees it, identifying bottlenecks should be straightforward.
“There’s lots of complicated things to solve with this, but the turnaround time on the labs, to me, it’s easy to see where the critical control points are, and it’s a matter of fixing them," Humble said.
Last week, the governor announced the state would put $2 million toward new equipment for Sonora Quest. With that, the laboratory hopes to be able to process 35,000 tests per day by the end of July — five times what it processes now. Its target is 60,000 per day by the end of August. Sonora Quest says its goal is to get processing time down to 24 hours.
If all of those goals are achieved, Humble said it will dramatically improve the state’s contact tracing capabilities.
But challenges remain. Coronavirus cases in Arizona quadrupled in June. And Sunenshine said research suggests there could be up to 10 times more COVID-19 cases in the community than what health officials have identified.
“Full, traditional contact tracing is no longer as effective once you have community spread," Sunenshine said. And she said an efficient contact tracing system is only one factor in containing the virus.
Sunenshine said the only way to effectively reduce cases is to combine testing and contact tracing efforts with requirements that people wear masks and stay apart from one another as much as possible. That, she said, requires policy change.