Westborough officials detail data discrepancies due to at-home COVID-19 tests


A rapid at-home test. (Photo/Laura Hayes)

WESTBOROUGH – Westborough’s COVID-19 case counts may be on the low side due to at-home tests, which Board of Health member Alan Ehrlich said are not being picked up by the alerting system.

“Unless someone does notify us, we don’t know that they’re positive and therefore our case counts are on the low side,” Ehrlich said during the Board of Health’s Jan. 3 meeting. “We don’t know by how much, but we know that there are definitely more people infected than what we’re reporting.”

Chair Nathan Walsh said people who use at-home kits and test positive should contact the Board of Health for further guidance. They should also follow-up with a PCR test. 

The Board of Health can be reached at 508-366-3045. 

Director of Public Health Jennifer Sullivan said staff began adding the at-home numbers to the case counts this week.

“Prior to this week, we have not,” Sullivan said.

She said on Monday night that about eight cases were reported to the Board of Health that day. 

Current cases

The board’s most recent report dated Dec. 30 reported 166 new cases since Dec. 23, which was the highest number of new cases in a single week since the start of the pandemic.

Ehrlich already noted concerns about incomplete data in a statement attached to that report.

Meeting on Monday, the Board of Health later unanimously approved an indoor mask mandate that went into effect on Wednesday of this week. 

Sullivan said that the 48 hours prior to the onset of symptoms in current COVID-19 cases is “very important” as one of the virus’ most contagious periods. 

She said she believes a high number of transmissions have been from infected people who were around others during this 48-hour period. 

People are gathering with loved ones without masks, she said.

In other cases, people are asymptomatic but getting tested because a loved one is requiring it before traveling or a gathering. 

Some are not isolating while waiting for their test results, Sullivan said. 

Board member Melissa Mahr added that there are people who had a “pretty substantial” exposure, but not testing positive.

“So, it is really important for people to continue masking, get tested after their exposure, talk to their doctors, but we’re seeing so much of that exposure from indoor gatherings, lots of family members,” Mahr said.

Other flaws in the data 

The reporting of at-home tests was one of the problems with current data that Ehrlich identified during the Board of Health’s meeting this week. 

“We need to understand that there are now flaws in the data that we didn’t previously — or at least I wasn’t as aware of — and that may have some impact in what we report in the future,” Ehrlich said. 

According to Ehrlich, Westborough doesn’t get its information regarding hospitalization rates from hospitals or the state, but from contact tracing. 

“With the spike in cases, clearly that’s becoming harder to do in a reliable fashion,” he said.

Ehrlich also said the numbers that the town was reporting for breakthrough cases were “not accurate.” 

He said he stopped by the health department on Monday to talk with Sullivan about a project he’s working on with medical students. 

They looked up Ehrlich’s information in the Massachusetts Virtual Epidemiologic Network — or MAVEN, which says on its website that it allows the state and local health departments to capture relevant information for infectious diseases. 

“It shows I’m unvaccinated,” Ehrlich said.

But another system — the Massachusetts Immunization Information System, or MIIS — said correctly that he had received both his COVID-19 vaccination and his booster shot. 

“The MAVEN system, which is reporting out to us who is infected, isn’t giving us reliable data on who’s been vaccinated or not, and it would be a very laborious process to look up each person in the MIIS system,” Ehrlich said.

Walsh clarified that the town does have access to the accurate information. But the discrepancy is in the easier-to-use system that the town is using for contact tracing.

Sullivan said the town and schools use different data, but that the Board of Health works out of the MAVEN system that provides it with the results of PCR tests. 

At one point, the system was reporting vaccine numbers, she said. 

“However, I think with the uptick in cases, I’m not sure why — even Dr. Ehrlich before the uptick in cases — it wasn’t added,” Sullivan said. “We’ve caught a few here and there when we had a chance to look. So, I’m not sure exactly why now there’s no vaccine record.”

She assumed that issue may be due to a backlog. 

Walsh asked if the department had the bandwidth to check each case with MIIS to check vaccination statuses. 

“Unfortunately [if] the caseload stays the way it is currently, there’s no way that we have the ability to do that to go by case by case in each,” Sullivan said. “We just got done from the caseload we had today right before the meeting, and that’s not looking at the vaccine because we are calling everybody.”


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