Scientists say many UTIs are caused by E. coli in food—when will the government believe them?

The connection between food and UTI-causing E. coli was first suggested long before even the Berkeley researchers found the same bacteria in three different states.

In 1970, a group of researchers examined “hospital food, the hospital kitchen, the meat on arrival in the hospital, and the meat and the environment in an abattoir and a poultry-packing station” for the presence of E. coli, and found the bacteria everywhere they looked. They wrote that it was likely the bacteria could be transmitted to humans by food and food preparation. They further hypothesized that “the administration of antibiotics to animals may be followed by the establishment of antibiotic-resistant strains of E. coli in the human bowel, with the subsequent appearance of urinary-tract infections which are more difficult to treat.”

That work was remarkably prescient, but a 2018 paper published by the journal of the American Society for Microbiology notes that the idea did not gain much traction for nearly three decades. Then, UTI outbreaks in Denmark, Canada, and the U.S., including those at the three America universities, prompted researchers to suggest that the infections were foodborne.

Much of Riley’s work since 2001 has been devoted to demonstrating that is the case.

In the past few years the Centers for Disease Control (CDC) has begun taking the issue slightly more seriously. In 2016, the agency awarded Riley and his team $560,000 to study whether food is a source of the antibiotic-resistant bacteria that causes UTIs. The resulting research certainly suggests so: In a 2018 paper they reported finding more than 90 distinct genotypes of E. coli in meat samples from Northern California, 12 of which were found in both human UTI and meat samples.

And yet: UTIs are not monitored by the government like a foodborne infection, or treated with the same seriousness as gastrointestinal infections. The CDC is funding research into the subject, but the agency acts like it’s still an open question.

“There are surveillance systems for all kinds of diseases, including all kinds of infectious diseases, but UTI is not included right now,” Riley says. “Our feeling is that it should be included. But that’s something still under discussion.”

The National Antimicrobial Resistance Monitoring System for Enteric Bacteria (NARMS) monitors antimicrobial resistance in enteric bacteria (like the pathogens that cause gastroenteritis) found in humans, retail meats, and food animals. Then there’s the National Surveillance of Bacterial Foodborne Illnesses, which also monitors bacterial pathogens.

“Drug-resistant, community-acquired UTI could be included among any one of these surveillance systems, if CDC can be convinced that a substantial proportion of these may be foodborne,” Riley says.

UTIs, like your everyday cold, are among the most common infections, especially in women. This is perhaps one reason they are not monitored in any serious way. If so, Riley disagrees with this reasoning. Unlike the common cold, Riley says, a UTI is a gateway disease, meaning it can often lead to more advanced forms of life-threatening drug-resistant infections. That’s why monitoring the spread of drug-resistant UTIs is so important.

Steven Roach, the Food Animals Concerns Trust (FACT) food safety director and project lead of the program Keep Antibiotics Working, concurs with Riley.

“[USDA] are collecting samples of E coli from livestock at slaughter as part of NARMS, so they could do a better job looking for and reporting on strains that cause human disease, including UTIs,” Roach says. 

Roach also wants to see the FDA reclassify uropathogenic E. coli as foodborne so that antibiotics used to treat the bacteria in agricultural settings are more tightly regulated.

The industry has supposedly curbed its use of antibiotics in response to fears and regulations regarding drug-resistant “superbugs.” Antibiotics are not supposed to be used for growth promotion in the U.S. anymore, and are similarly banned or restricted in many other countries; moreover, the FDA has said they want to curtail their use as an indefinite, preventative anti-infectious measure.

Reducing the use of antibiotics in agriculture could curb the spread of drug-resistant pathogens like E. coli, but even if the FDA made this the highest priority, it might not make a huge difference. Riley points out that it’s a global problem, and we have a global food system, and so any steps we take just in the United States won’t be sufficient. Moreover, scientists have found that the genes that makes different pathogens drug-resistant can jump between species, so the spread of drug-resistant bacteria and other pathogens will likely continue one way or another.

“If we don’t start doing something about this now,” Riley says, “it can become an even bigger problem in the future.”