Rice University Discovers Inaccurate COVID-19 Positivity Rate After Delaying In-Person Classes

COVID-19 sample vials at a testing lab in Houston, on Aug. 13, 2021. Brandon Bell/Getty Images

Rice University in Houston, Texas, announced last week that the first two weeks of the fall semester would be moved online because of a high number of COVID-19 cases among students. It now says the data the decision was based upon were flawed.

In an Aug. 22 letter to the campus community, Rice’s Vice President for Administration Kevin E. Kirby said “anomalies” in the initial testing data prompted the university to retest dozens of students deemed positive for COVID-19, and “all but one of those have turned out to be negative.”

According to the letter, Rice started to ramp up its testing program on Aug. 13 with three different test providers and conducted about 4,500 tests over 9 days with initial results showing 81 positive results. This positivity rate of 2 percent, although much lower than that of the city of Houston, Kirby said in the letter, was still concerning enough that the university officials delayed the start of in-person classes.

“For Rice, a 2 percent rate would be significantly higher than our historical positivity rate of 0.24 percent over the last year when we ran about 150,000 tests,” Kirby said. “This unusual campus positivity rate prompted us to take quick action and assume a more cautionary posture until we could determine whether there was a significant risk of widespread infection.”

Rice began investigating the results when it realized that over 90 percent of the positive infections came from a single test provider, and most of those cases involved people who reported no symptoms or had been fully vaccinated. It turned out that the provider had changed its testing protocol without the university’s knowledge.

“Then we retested about 50 people who initially tested positive. Each of them was tested two additional times, on two different days, by two different test providers, and all but one came back negative,” Kirby wrote, adding that the university released students who were falsely determined to be COVID-19 positive from isolation.

Rice officials said they'll stick to two weeks of online classes, considering that many of the students and faculty had already adjusted their plans based on that schedule. But students who were told to delay moving on campus until after Sept. 3 can now move in as soon as they want.

“Our commitment is to be fast, flexible, and nimble responding to anything involving the safety of individuals and the overall health of our community,” the letter reads. “We recognize and regret that these testing anomalies have caused tremendous difficulties for all involved.”

In Houston, the public health agency has reported over the past weeks increasing cases of COVID-19. Earlier this month, Mayor Sylvester Turner defied Gov. Greg Abbott’s order of no mask mandates, requiring that the city’s nearly 22,000 public employees wear a mask inside city buildings where they can’t keep a physical distance.