There’s been a long-standing belief that urinary tract infections are largely caused by poor personal hygiene. New research, however, suggests that many cases may actually be caused by infections of E. coli bacteria from contaminated meat purchased in grocery stores.
UTIs are common — globally there are 400 million cases a year — and can occur when bacteria enter the urethra and infect the urinary tract, according to the U.S. Centers for Disease Control and Prevention.
Though public health agencies including the CDC have made clear that E. coli can cause UTIs, the information they provide is often vague. Usually, when E. coli comes up on agency websites, it’s in the context of the strains that cause diarrhea.
A new study published on Thursday in the science journal American Society for Microbiology puts the spotlight on the strains of E. coli that cause UTIs.
Between 2017 and 2021, researchers from George Washington University and Kaiser Permanente Southern California collected more than 5,700 urine samples that tested positive for E. coli from U.S. patients with UTIs who resided in Southern California, from Bakersfield to San Diego.
The researchers also took samples from meats (including turkey, chicken, pork and beef) being sold at retail locations in the neighborhoods where those patients lived.
By comparing the those two sets of samples, the researchers determined that approximately one in five of those infections could be tied to exposure to E. coli from contaminated meat that was purchased in the U.S.
“Urinary tract infections have long been considered a personal health issue, but our findings suggest that they are also a food safety problem,” said Lance Price, senior author of the study and professor of environmental and occupational health at George Washington University.
Among the meat samples, E. coli contamination was highest in chicken (found in 38% of samples collected) and turkey (36%), followed by beef (14%) and pork (12%).
According to the study, food-borne UTIs disproportionately affect women, as well as people living in lower-income areas.
Women are much more prone to the infection in general because of their anatomy. Women have a shorter urethra — the tube that carries urine from the bladder to outside the body — and the short distance makes it easier for bacteria to travel up the urethra and into the bladder. It’s unclear, however, why food-borne UTIs would affect women more than men.
It’s also uncertain why there is such a strong correlation between food-borne UTIs and people who live in high poverty areas. However, the study did find that E. coli contamination was more common in “value packs” of meat; i.e. products that contain larger quantities of meat sold at a lower price per pound.
“My own experience of actually going to grocery stores in more affluent communities versus low-income neighborhoods is that the quality of the products are lower” in the latter, Price said.
The study also suggested that factors including storage at improper temperatures, lack of proper safety and hygiene practices during handling, and production in unsanitary conditions could all have contributed to E. coli contamination.
Price said he and his team sometimes saw packages of chicken that were “bloated with saline.” The extra water could have been the culprit of the E. coli contamination if it leaked onto check-out conveyor belts and contaminated other grocery items.
While Price believes that our food supply chain could do more to lower the risk of food-borne UTIs, consumers can practice safe handling of foods to lower their risk of exposure. That includes:
- Purchasing meat and poultry that is securely sealed to prevent leakage onto other groceries.
- Thoroughly cooking all meat and poultry products. A complete list of recommended temperatures for whole cuts of beef, ground meats and poultry can be found on the CDC website.
- Avoiding cross-contamination in the kitchen.
- Washing hands and kitchen surfaces after preparing raw meat.
