A data dilemma: Omicron lifted Idaho’s COVID test backlog higher than ever. Here’s why
The omicron variant caused Idaho’s fifth major COVID-19 surge, and it surpassed all previous waves by some metrics, causing record numbers of new cases and community infection levels.
Accompanying the larger surges has been a corresponding breakdown of the state’s data reporting. When case numbers rise precipitously, public health workers are unable keep up, leaving positive test results unreported for days.
The data difficulties have illustrated the limited resources health departments have to track disease rapidly. At the same time, some are questioning whether daily case counts are even the right focus.
Case backlogs have been an issue in many states, but Idaho’s problems have revealed how the state’s data reporting breaks down during the most critical periods of the pandemic.
“The sheer volume of positive labs and the rate of increase at which they’re coming in is just untenable,” said Dr. Kathryn Turner, deputy state epidemiologist, at a recent press briefing.
Cases were backlogged in December 2020 and again in September 2021, but this year, when omicron infections soared, it became much worse.
In October, for instance, the state’s backlog rose to exceed 11,000 positive tests, as the state recorded nearly 83,000 cases between the middle of August and the end of October. This year, the surge has been much larger and faster, with more than 82,000 cases recorded just since mid-December, and a peak backlog exceeding 44,000 positive tests.
(Health officials note that not every positive test represents a new case, for multiple reasons, including the possibility that the same infected person may choose to get tested multiple times over a short period.)
‘Anywhere from moments to minutes’
Each time a positive lab result is reported to the state by a health provider, one of the state’s seven public health districts conducts a case investigation. Employees at the health districts first review the collected information and verify that the person who tested positive is a resident of Idaho, after which the case is submitted to the Department of Health and Welfare for inclusion in the state’s data dashboard.
Later, investigators attempt to contact the person who has tested positive and gather any information they can about their illness for input into the statewide system, Turner said.
When the cases start piling up, the initial verification can lead to delays, especially if there is an issue with the listed address, such as an inconsistent ZIP code.
“It can take anywhere from moments to minutes for each of those investigations,” Turner said at a briefing earlier this month. “It is exceedingly difficult to turn those investigations around within 24 hours.”
Those delays then skew the state’s data significantly.
Recent estimates from health officials indicate that the state’s per-capita seven-day incidence rate in late January was likely close to twice as high as what the dashboard showed.
The state has asked health districts to consider not doing full case investigations in all cases, instead focusing on collecting a person’s vaccination status before moving on to the next case, Turner said.
Once the bottleneck of positive tests begins, the number of cases the state reports each day skews low — they account only for the number that investigators were able to process that day, rather than the total number submitted.
Later, when a surge declines, the reverse can occur: The state reports more cases per day than were actually obtained, as investigators wade through the backlog.
A job for local Idaho health districts
The Idaho health districts were created in the 1970s and have had epidemiology programs since their inception, Turner said.
Though Health and Welfare administers the state dashboard and receives federal grants through the Centers for Disease Control and Prevention, the state’s local public health districts are autonomous agencies, and their personnel are not overseen by the state.
Two districts cover North Idaho, including the Panhandle, while five are spread across the rest of the state. District 4, or Central District Health, covers Ada, Elmore, Boise and Valley counties. District 3, or Southwest District Health, covers the area west of Boise and Meridian all the way to the Oregon border: Canyon, Gem, Payette, Washington, Adams and Owyhee counties.
About 90% of the state’s funding for epidemiology and surveillance comes from CDC grants, with Health and Welfare entering into sub-grants with the local health districts to conduct specific data activities and report to the state.
State spending has gone up considerably since the pandemic began.
In fiscal year 2020, which ran from July 1, 2019 to June 30, 2020, the epidemiology and surveillance budget was $1.8 million. The next year, it was $12.4 million, and it rose to a projected $15.9 million for FY 2022, which ends in June, according to Turner. The budget for fiscal year 2023 is expected to be similar.
Central District Health, which has around 30% of the state’s population, has been responsible for much of the backlog.
As of Jan. 31, the health district had a backlog of 25,040 electronic reports of positive tests dating back to Jan. 6, according to a spokesperson, Rachel Garceau. The district also had an “unknown number” of faxed reports that had not been processed.
The district has nine full-time and three part-time investigators, and the communicable disease team further consists of data and records staff. The district also uses some volunteers and “surge support” from other staff members. Before the pandemic, the team had five members, which has increased at times to more than 50 people during the pandemic and is now about 25, Garceau said.
CDH is currently evaluating investigator applicants but has had “difficulty identifying high-quality” candidates, Garceau said in an email.
“It is not a field most people traditionally train for or seek out,” Lindsay Haskell, the district’s communicable disease control manager, said in an emailed statement. “Many of our initial COVID staff were workers displaced due to the pandemic who have not returned to their original fields.”
Garceau added that the investigation work can be difficult, as staff “often work with families that have just lost a loved one, people who are ill, those who may be angry about a child unable to go to school, or someone that just does not want to discuss COVID.
“Many investigations go smoothly, but sometimes investigators are yelled at,” she said.
How do Idaho’s neighbors compare?
Historically, epidemiological data has not been of interest to much of the public in real time, Turner said. State health departments have generally released data with less frequency while monitoring disease in an effort to reduce prevalence in communities.
But during the coronavirus pandemic, that has all changed.
State’s have built data dashboards, where case and testing statistics, as well as hospitalization and vaccination numbers, are tracked and updated daily.
But the way each state processes COVID-19 data differs, and Idaho’s neighboring states are not all facing the same issues.
In Montana, the state has faced a backlog brought on by the omicron surge.
“Many local health departments have been overwhelmed by the number of cases being reported to them every day, and have not been able to keep up with the demands of case entry into the reportable disease surveillance system,” said a spokesperson for the Montana Department of Public Health and Human Services, Jon Ebelt, in an email.
On Jan. 21, the state “transitioned to automatic case creation,” Ebelt said, “which has allowed for automatic processing and reporting of positive COVID lab reports.”
Turner said up to 30% of positive labs in Idaho will never end up as a counted case, though.
“Going back and correcting those (cases) backwards I think would do more harm than good for the public, who are trying to figure out whether or not there’s something brewing in their jurisdictions,” she said.
In Washington, the state was reporting 41,535 backlogged cases as of Jan. 26, with up to 7,000 duplicate cases, spokesperson Teresa McCallion said via email.
COVID-19 data in Washington are processed first automatically and then manually by epidemiological staff, before cases are officially reported.
Washington’s data processor — a machine used to process positive and negative lab results — initially had a capacity limitation of 30,000 test results per day. The state has been receiving twice that number, and a new, recently installed processor can handle up to 100,000, McCallion said.
In Oregon, the state never has had a backlog of laboratory results, according to a spokesperson for the Oregon Health Authority, Rudy Owens.
Owens said in an email that the state’s database “is able to handle the large influx of test results that have come in with the omicron surge.”
Utah is in a similar situation, with the health authority reporting no backlog of cases during the surge. But in Utah, positive lab results that are submitted to the state are automatically processed into cases, with adjustments made later.
Afterward, “as we conduct investigations, we will add or remove cases based on what is necessary,” said Tom Hudachko, spokesperson for the Utah Department of Health, via email. He said one of the most common adjustments is “for people who are not Utah residents who initially get counted as a case.”
Wyoming, the nation’s least populated state (roughly 582,000 people), has reported no backlog on case data during the omicron surge, although some other information, such as the state’s numbers on cases organized by date of symptom onset, can be delayed, said Kim Deti, a spokesperson for the Wyoming Department of Health.
‘Not making sense to count every case anymore’
Twenty-three months into the pandemic, the approach to and opinions of daily case data may be changing.
In March 2020, the first documented cases of COVID-19 in the U.S. were examined fervently. But as cases began to mount quickly, a detailed focus on each one became insurmountable.
Now, with caseloads in Idaho higher than they’ve ever been, some health officials wonder whether a minute focus on daily cases is still a significant metric.
“It’s just not making sense to count every case anymore,” Turner said. “It’s out there. Everybody knows it. Knowing whether or not there’s 2,100 cases a day or 2,103 cases a day doesn’t make a lot of difference in policy action.”
And with the increased prevalence of rapid tests, which are not processed by labs, many COVID-19 infections are certainly going unreported. The state knows of about 50-60% of the infections in Idaho, Turner estimated.
She said the more important surveillance was to look at trends in the positive cases, including whether they lead to more hospitalizations or deaths; whether a particular variant is having more of an impact on a specific age group; how differently it’s affecting vaccinated versus unvaccinated people; and whether it’s concentrated in congregate settings.
“It is almost harmful to do nothing but count,” Turner said. “The last thing we focus on is numbers. The first thing we focus on is the people.”
Some other public health experts agree, arguing that case levels no longer convey the risks being posed in different populations, given that many people are now vaccinated or have some acquired immunity.
“Case numbers were once a reliable indicator of population risk, accurately foreshadowing hospitalizations and deaths, but this is changing as more of the country attains some level of immunity,” wrote Joseph G. Allen, an associate professor at Harvard University’s T.H. Chan School of Public Health, in The Washington Post in September.
Turner said the ongoing pandemic has pushed state health agencies to examine their data systems. Though software has been updated, the state has been using the same epidemiological data system since 2002.
“(The pandemic) has pushed us to really take a long, hard look at ourselves and determine what we can improve,” she said. “It’s made public health step back and say, ‘Maybe we need more modernized systems, maybe we need to think about doings things a little bit differently.’”
This story was originally published February 11, 2022 at 4:30 AM.
