UTIs Might Be Coming From Your Grocery Cart

Here’s something to unnerve you during your next trip to the supermarket. Research out this week shows that a substantial portion of urinary tract infections can be traced back to store-bought meat tainted with dangerous Escherichia coli bacteria.

Researchers at George Washington University and others examined thousands of samples taken from people with UTIs. They found that roughly one in five infections were likely caused by foodborne strains of E. coli. The results suggest that contaminated meat is an underappreciated source of these often miserable infections, the researchers say.

“These findings highlight zoonotic transmission as an important driver of UTIs,” they wrote in their paper, published Thursday in the journal mBio.

The origins of a UTI

UTIs are one of the most common infections around, and they’re estimated to result in 3 million visits to the emergency room in the U.S. alone every year. Over 80% of UTIs are caused by E. coli. These bacteria are found most everywhere, including the guts of people and many of the animals that we regularly eat, though only some strains can make us sick.

The George Washington University researchers have been investigating the possibility of foodborne UTIs for quite a while.

In 2018, for instance, they published a study showing clear evidence of human UTIs caused by E. coli bacteria first found in store-bought meat, especially chicken. But the researchers say it’s still been unclear just how often UTIs are likely to originate from food, particularly in major metropolitan areas. To help answer this, they teamed up with other researchers at Kaiser Permanente Southern California.

Together, they collected a large amount of E. coli samples from both real-life UTI patients in Southern California and packages of retail meat, ultimately sequencing the genetics of over 5,000 samples. They then developed an algorithm, based on 17 specific genetic markers, to identify whether a particular sample of E. coli originally came from animals or humans.

All told, they found that 18% of human UTI infections diagnosed in the region between 2017 and 2023 were probably zoonotic in origin—foodborne, in other words.

Hidden meat risk

The researchers note that their findings are limited to a single, if large, region. So more studies should be done to quantify the extent of this issue in other parts of the country. But given their earlier research, it certainly seems likely that tainted meat plays a significant and underrecognized role in UTIs.

“Urinary tract infections have long been considered a personal health issue, but our findings suggest that they are also a food safety problem,” said senior study author Lance Price, a professor of environmental and occupational health at George Washington University, in a statement from the university.

The current findings might also help inform prevention efforts moving forward. The most dangerous foodborne UTI strains tended to come from chicken and turkey, for instance. And people living in low-income neighborhoods were more likely to have foodborne UTIs.

Fortunately, the same tips used to prevent foodborne illness in general should also lower your risk of these UTIs. That includes buying meat that’s securely sealed and won’t leak onto your other groceries, thoroughly cooking your meat, and washing your hands after handling raw food.