Houston’s Daily Covid-19 Tally Inflated by Months-Old Cases

(Bloomberg) -- Houston-area health authorities are overstating the number of new Covid-19 cases as data teams struggle to work through a backlog of old test results in the third-largest U.S. county.

On an almost daily basis, Harris County Public Health releases a tally of what it calls “new cases.” A Bloomberg analysis found they include hundreds of diagnoses that are weeks or months old. On Wednesday, for example, more than 82% of the new cases disclosed were actually detected prior to this month and some dated as far back as May.

The confusion means authorities may be exaggerating the current severity of the outbreak -- and were unknowingly understating the extent of the crisis in June and July, when hospitals were stretched to their limits. The situation also highlights the dilemma facing political leaders imposing mask mandates and other restrictions based on what they presume is accurate, timely data.

Texas Governor Greg Abbott signaled he may relax some anti-virus restrictions as soon as this week. The Republican leader was widely blamed for fanning a resurgence in the outbreak when he reopened the economy in May, only to reverse himself before the end of June. Meanwhile, Houston Mayor Sylvester Turner extended the ban on parades, festivals and 5K runs through the end of the year, although limited-capacity events such as the symphony and football tailgate parties will be allowed.

“This is a big thing, to name the numbers,” said Dizhi Marlow, a spokeswoman for Harris County Public Health. “We don’t want to give people a false sense of the increase.”

Almost eight months into the worldwide outbreak that’s killed more than 900,000, governments and public-health authorities are still grappling with whether and how to reopen paralyzed economies. Europe and India are on the brink of new waves of infection while New York City plans to allow restaurants to serve diners indoors, albeit at reduced capacity.

In Texas, Harris County’s overstatements have been unintentional and the result of a deluge of sometimes incomplete data from state health officials dealing with a backlog of test results, Marlow said. While the county works on clearing the excess of old cases, it is trying to find a way to provide the public with a clearer picture of how many of the new cases are really new, she said.

Of the 723 “new” cases reported by Harris County on Wednesday, 98 dated to August and 217 were from July, the data showed. Another 274 and 3 were from June and May, respectively.

“They’re calling them new cases because they are new to them,” said Joe Wohleber, a Houston engineer and data analyst who was one of the first to highlight the discrepancies in a series of social-media posts. “But what do cases from June and July have to do with what we’re dealing with on the ground now?”

Information Gaps

Because of the challenges involved in obtaining real-time figures, Harris County Judge Lina Hidalgo has been using an array of data points to assess the progress of the virus. Hidalgo, the highest-ranking county executive, has been an ardent advocate of strict controls to combat the pandemic.

“Local health officials, local media, and residents have known state backlogs have been an issue since the start of the pandemic which is why when it comes to making policy decisions we do not rely on daily case counts alone,” a spokesman for Hidalgo said in an email.

Harris County has been receiving data dumps of old cases a couple of times a week and is still trying to work though the backlog.

One of the challenges of processing the information is that some test results are missing addresses or phone numbers, which complicates figuring out whether to assign them to the city of Houston or a suburban area outside the municipal limits, Marlow said.

‘Under The Bus’

David Persse, Houston’s director of emergency medical services, said it may be unfair to “throw the state under the bus” given the unprecedented mass of testing data flowing into a computer system that until very recently wasn’t up to the task.

Collecting personal information about those who test positive has also been complicated by the use of stadium-sized testing facilities that aren’t set up to gather the same level of detail as traditional physicians’ offices. Previous outbreaks of meningitis and tuberculosis were simpler to track because initial reports originated from doctors rather than mass testing clinics, Persse said.

The Texas Department of State Health Services more than doubled its test-processing capacity at the beginning of August to cope, and has been training labs and hospitals in how to properly code filings so they move smoothly through the state’s system, Lara Anton, a department spokeswoman, said Wednesday. Backups and glitches also were traced to computing-language conflicts and the archaic use of fax machines in some corners of the state to submit reports, she said.

Other counties around the Lone Star state already have figured out how to parse new cases from old ones. Nueces County, which includes Corpus Christi, notified residents on its virus dashboard that the 38 cases reported there for Monday excluded five newly-discovered diagnoses from earlier dates. Dallas and other counties routinely do the same.

“I don’t think this is a Harris County issue because this all stems from issues at the state level,” Wohleber said. “But what the county can control is the phrasing of their new-case language.”

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