After McDonald's announced that the E. coli outbreak connected to the fast food chain's Quarter Pounders could be affecting Oklahomans, some health professionals have questioned if the state's testing and reporting are sufficiently up to date.

On social media platform X, Dr. George Monks, a past president of the Oklahoma State Medical Association, stated that Oklahoma is the only state with a state lab that cannot perform foodborne illness tracking testing . The concern, he told KFOR Wednesday, is that delays in testing could worsen an ongoing outbreak.

However, the Oklahoma State Department of Health says they E. coli infections in-house, and without delay to results, said Erica Rankin-Riley, the department's public information officer.

How does E. coli testing work?

The process starts with a test conducted by a patient's healthcare provider, which is then tested at the department, Rankin-Riley said. When a positive test is found, it is sent to the Oklahoma Public Health Lab where the investigation begins.

Rankin-Riley said the most common causes of E. coli, listeria and salmonella are reportable diseases investigated by epidemiologists and communicable disease nurses across the state. The department's epidemiologists conduct robust investigations for each positive case, helping them identify clusters or outbreaks throughout the state.

“Investigations involve collecting potential exposure information from the case and working to identify any commonalities that may be suggestive of a foodborne outbreak,” Rankin-Riley said in a statement.

Does Oklahoma test or track E. coli in-state?

The department's website states that their whole genome sequencing, or WGS, testing is sent to the Nebraska Public Health Laboratory departments, but Rankin-Riley said testing does happen through the Oklahoma Public Health Laboratory.

"The Oklahoma Public Health Laboratory tests for foodborne illnesses, including E. coli O157:H7," Rankin-Riley said.

When asked outright if they send their WGS testing to Nebraska, specifically for E. coli, Rankin-Riley said, "The OSDH continues to monitor the outbreak and will investigate any reported potential cases."

Previously, the Oklahoma Public Health Lab did outsource some of its testing to Nebraska in 2020, Rankin-Riley said, after Oklahoma's lab relocated to Stillwater. Now, they conduct infections using molecular and culture-based methods in-state.

"The only testing done by the Nebraska Public Health Lab is advanced genetic analysis to find linkages between cases, which does not delay results for Oklahomans," Rankin-Riley said.

She noted the Stillwater lab monitors foodborne illnesses through "numerous avenues" and genetic analysis is just one of the ways they do so.

Is McDonald's safe to eat? What states are affected?

McDonald's has temporarily removed the Quarter Pounder from restaurants in the potentially impacted area out of "an abundance of caution," which includes some stores in Oklahoma, according to a statement released Wednesday.

And Oklahoma's health department determined that no reported cases of E. coli related to McDonald's have been reported in Oklahoma, Rankin-Riley said.

McDonald’s said that initial findings indicate some illnesses may be linked to the slivered onions used in the Quarter Pounder, which is sourced by a single supplier that serves three distribution centers.

The fast food chain also said it was working with suppliers to replenish supply for the Quarter Pounder in the coming weeks, and that other menu items are unaffected and available.

“We take food safety extremely seriously and it’s the right thing to do,” said the statement from Cesar Piña, the fast food restaurant’s North America chief supply chain officer.