HOUSTON, Texas (KTRK) -- The state health department says it is no longer using one of the labs it relies on for COVID-19 testing at nursing homes across Texas following concerns of "anomalies resulting from recent nursing home and community surveillance testing."
Last month, Gov. Greg Abbott directed the state to test every single nursing home resident and staff member for the virus, but 13 Investigates learned Friday it is possible some of those tests resulted in "false positives."
RELATED: 13 Investigates: First look at nursing homes with worst COVID-19 outbreak
One of the labs it works with reported an "an unusual number of positive results among people without symptoms in a few nursing homes, raising the possibility of false positives," according to the Texas Department of State Health Services.
"This laboratory has run approximately 14,000 tests from nursing facility and community sampling efforts and there are exceptional results in a small number of facilities," a Texas Health & Human Services Commission spokesperson said in a statement to 13 Investigates. "The state will not use this lab for COVID-19 testing until the issue can be resolved."
13 Investigates asked the Texas Health & Human Services Commission which lab it is no longer using, but the agency did not provide that information Friday. It says it will not use that lab "until the issue can be resolved."
The state says it reached out to facilities tested by the lab "to explain the situation and offer options for additional/repeat testing."
DSHS is recommending that no action, such as isolation and quarantining based on the test results, be taken "with those facilities receiving an abnormal positivity rate among asymptomatic residents."
It is relying on local health officials and facility administrators to decide appropriate action.
Regarding facilities that used one of the other laboratories, the state says "there is no information to cast doubt on the validity of test (those) results."
Still, the news is another setback in allowing residents to know which nursing homes across the state have the worst COVID-19 outbreaks.
This week after the federal government released COVID-19 case and death data for hundreds of Texas nursing homes, but hundreds more have yet to report the information and could face a fine if they don't.
In Texas, 40 percent of COVID-19 deaths are at nursing homes, according to the latest state data available Friday.
The data released Thursday by U.S. Centers for Medicare & Medicaid Services provides some more details about individual Medicare-skilled nursing facilities and Medicaid nursing facilities.
INTERACTIVE: Want to know how many COVID-19 cases are your or your loved ones nursing home? 13 Investigates mapped out every facility in Texas and how many residents and staff members were diagnosed or died. The red dots indicate facilities that did not provide information and the larger blue dots indicate facilities with cases. On mobile device? Click here for a full screen experience.
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13 Investigates: State stops using lab after 'abnormal' COVID-19 test results
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