Case data lag slows contact tracing of COVID-19

John Orona
Special to the Sierra Sun

Despite adding over 180 COVID-19 cases in the last month, more than doubling Nevada County’s cases in that time, public health officials say the increase may represent an undercount.

State Health and Human Services Secretary Mark Ghaly said Tuesday an electronic glitch in the system that sends COVID-19 test information from labs to state and county health departments has caused a delay in reporting results that doesn’t provide an up-to-date picture of transmission and sets back contact tracing efforts.

The glitch does not affect death or hospitalization statistics and test results are still able to be reported from labs directly to county public health officials, Ghaly said. That led the state to temporarily stop monitoring its list of counties that may need state help in slowing infection or hospitalizations.

According to Nevada County interim Public Health Officer Dr. Richard Johnson, beyond keeping the county off the state’s monitoring list, there’s no telling how the glitch will affect the county’s case count once the actual numbers are in.

“We’re not sure if (the glitch) was just the last couple of weeks or longer than that. We do not know to what extent it’s going to change things, or how bad or how good it’s going to be for us,” Johnson said.

“What we do know is hospitalizations and ICU bed use has been down 7% to 10% over the last week or so (statewide) and that’s very encouraging,” Johnson added. “We’ll get the accurate numbers eventually, but the state has not given a timeframe on that.”

Beyond the potential undercount, Johnson said the county is concerned with how long wait times for test results are affecting contact tracing efforts, forcing the public health department to focus on cases whose results came back quickly.

“We have prioritized our contact tracing efforts to test results that come back in a timely fashion, where we can actually do something about it and take action that will result in a change in community transmission,” he said. “If a result comes in past 14 days, there typically is very little we can do to influence what’s going on in the community at that point.”

According to public health officials, patients can wait for test results anywhere from four to 12 days, with contact tracers assigned to a positive case generally within 24 hours of notification of a positive result. Typically, symptomatic carriers start to feel effects within two to six days of exposure, Johnson said, and it may take days after onset of symptoms to get a test appointment, depending on patient priority.

Health officials said the county’s OptumServe test only takes appointments up to a week in advance, meaning if the rest of the week is booked by Monday a patient will have to wait up to seven days.

Johnson added testing in health care facilities is prioritized and results return much more quickly, sometimes within 30 minutes.


These are on top of the challenges already inherent to contact tracing, like getting information from patients and convincing them to quarantine or isolate if needed.

“Many times, either because we don’t have good information, people are not completely forthright, or they forget where they’ve been or who they’ve been close to, it’s very difficult,’ Johnson said.

Additionally, it can be hard for both business owners and employees to follow isolation orders knowing the economic impact. According to public health officials, the county has worked with multiple employers, including grocery stores, about diagnosed employees.

“We continue to be bothered by the fact that there are close contacts of those who are COVID-19 positive who are showing up, especially in the workplace. We are finding people who ought to know better with mild symptoms still continue to go to the workplace and then the ripple effects from that are not just a ripple but there’s a tsunami effect,” Johnson said.

Public health officials said the county offers quarantined patients resources to help them maintain isolation and few patients refused to quarantine.

“This is about individuals taking the responsibility to protect themselves, their households and their community, that’s much more important than anything government does at this point,” Johnson said. “The bottom line is — what will individuals decide to do to help protect themselves?”

John Orona is a reporter for The Union, a sister publication of the Sierra Sun based in Grass Valley. Contact him at or call 530-477-4229.

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