Why San Antonio Metro Health cut hundreds of cases off its COVID-19 case tally

Most of the 619 cases dropped on Sunday were duplicate entries, bringing total cases to 41,082

San Antonio – Duplicate entries and out-of-county cases were behind the San Antonio Metropolitan Health District’s removal of 619 COVID-19 cases from Bexar County’s running tally over the weekend.

While the city reported 524 new COVID-19 cases on Sunday, the running tally actually dropped by 95 cases, from 41,177 on Saturday to 41,082 —a 619 case swing when including the new cases.

However, Assistant City Manager and acting Metro Health Director Colleen Bridger said removing the cases, which equaled about 1.5% of the total number, does not change the severity of the COVID-19 threat in Bexar County.

“These are cases that go back to March. So, no. It doesn’t change really anything about where we are,” Bridger said.

Bridger said the numbers were cut as the agency cleaned up its data in preparation for a switch to a new contact tracing system on Monday.

“So that when, starting tonight, we transition all of that data into the Texas Health Trace System, it’s all 100 percent accurate and ready-to-go,” Bridger said.

Most of the 619 cases removed on Sunday were duplicate entries, Bridger said, stemming from multiple reports for the same cases.

“We get notified by the lab, by their doctor, by the hospital. And so it’s not unusual to get notified about somebody COVID test results three or four, or sometimes even five times,” Bridger said, adding that there are even more if someone gets tested at multiple locations.

The problems arise if the reports come in with slightly different information. A misspelled name, a different date of birth, or an address that spells out “road” instead of using the “rd” abbreviation could all mean a report gets entered as a separate case.

An automated computer process rounds about 2,500 duplicate entries before they were ever reported as part of the city’s tally, Bridger said. However, in preparation for the switch from eMocha to Texas Health Trace System, a data team went through to find entries the computer missed.

While the duplicates the data team found by hand make up the majority of the 619 removed cases, Bridger said a small number were also cases that turned out to not be Bexar County cases.

While a handful of addresses may have appeared to be in Bexar County, she said, geo-coding them showed they were actually from over the county border —in Atascosa County or Comal County, for example.

Bridger said this kind of case data usually shared with the public years after the event. So, providing daily updates like the health department has been doing, she said, is “highly unusual.”

And as a result, there will be some adjustment that happens over time,” Bridger said. “And we’re trying to be as open and transparent about it as possible.”

Bridger said she does not expect to have the same duplication problems now that Metro Health has switched to Texas Health Trace, which she said is much better at allowing the department to verify it is not entering duplicate information.

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