A major new study reveals that almost one in five urinary tract infections (UTIs) in Southern California patients are caused by E. coli bacteria originating from contaminated meat. This four-year research reframes UTIs as a significant food safety concern, not just a personal health issue, with implications for millions across the United States.[cbsnews+3]
The study, published in the scientific journal mBio in October 2025, analyzed over 2,300 UTI cases in Southern California between 2017 and 2021. Researchers from George Washington University and Kaiser Permanente Southern California found that 18% of these infections were linked to E. coli strains genetically matching those found in meat samples from local grocery stores.Experts believe this hidden foodborne risk could affect millions nationwide, given the widespread distribution of meat products.[cbsnews+8]
Meat Contamination Fuels Infections
The research team used a genomic attribution method, comparing the DNA of E. coli from patients with strains identified in retail meat. This allowed them to estimate how many infections came from animal sources.They found that turkey and chicken were the meats most frequently contaminated with E. coli, followed by pork and beef.Contamination rates were highest in turkey at 82%, chicken at 58%, pork at 54%, and beef at 47% among sampled meats.The riskiest bacterial strains for causing human infections were most often found in poultry products.[cbsnews+19]
E. coli from contaminated meat can enter the human digestive system when people handle raw meat during food preparation or consume undercooked meat.These bacteria can then take up residence in the gut. From there, they can travel to the urethra and infect the urinary tract, leading to a UTI.[kgw+4]
Lance Price, a professor of environmental health at George Washington University and one of the study's authors, emphasized the frequency of the problem. "It's pretty frequent, one in five, and with better food safety, we could reduce it," Price told CBS News.He added that the finding reframes contaminated meat as a serious health hazard, not just a nuisance.[cbsnews+1]
Disproportionate Risk for Vulnerable Groups
The study also highlighted significant disparities in who is most affected by these foodborne UTIs. Women were found to be more than twice as likely as men to have UTIs caused by meat-origin bacteria, with nearly 20% of female UTI cases linked to such strains compared to 8.5% in men.Among men, those with foodborne UTIs were significantly older, with a median age of 73 compared to 65 for non-foodborne cases.[kgw+9]
People living in high-poverty neighborhoods faced an even greater risk, showing a 60% higher chance of foodborne UTIs compared to those in wealthier areas.Researchers noted that contamination rates increased by 12% for every 10% increase in a neighborhood's poverty rate.The exact reasons for this socioeconomic pattern are still unclear, but potential factors include inadequate food safety regulations in stores serving lower-income areas, improper storage temperatures, deficiencies in food handling practices, and products kept out too long before sale. Large, low-cost "value packs" also showed higher contamination rates.[cidrap+12]
Tara Smith, a professor of infectious disease epidemiology at Kent State University, who was not involved in the study, confirmed the plausibility of the findings. "When you're exposed to these organisms, by handling raw meat or eating it undercooked, they can take up residence in your gut and stay there," Smith explained. "Most UTIs come from your own gut flora. When that flora includes bacteria from animals, that's the connection."[cbsnews]
Public Health Implications and Prevention
Urinary tract infections are among the most common infections worldwide, with about 8 million cases diagnosed annually in the United States.While many UTIs resolve with antibiotics, severe infections can spread to the kidneys or bloodstream and become life-threatening.E. coli is the leading cause of UTIs, responsible for 80% to 90% of all cases.[kgw+13]
The study also exposes how farming and policy decisions can impact public health. Although the U.S. has banned antibiotics for growth promotion, farms still use them to prevent disease in crowded animal barns.This practice can lead to animals developing antibiotic-resistant E. coli strains, which can then be transmitted to humans.When humans are later exposed, these resistant strains can make UTI treatment more difficult.[cbsnews+8]
Price argues that regulators should treat E. coli in meat as a serious health hazard. He suggests stronger slaughterhouse hygiene, stricter contamination standards, improved inspections, and vaccinating animals against UTI-causing strains could help.The Centers for Disease Control and Prevention (CDC) guidance, which often focuses on diarrheal E. coli strains, may need updating to recognize foodborne E. coli as a widespread source of UTIs.[cbsnews+1]
For consumers, experts emphasize that people should not stop eating meat but must take precautions. These include thoroughly cooking all meat to kill bacteria, washing hands after handling raw meat, keeping raw meat separate from other foods, sanitizing cutting boards and surfaces, and avoiding cross-contamination from meat packaging.[kgw+4]
Betsy Foxman, a professor of infectious disease epidemiology at the University of Michigan, acknowledged the study's findings are "pretty convincing" and add to growing evidence that bacteria from food animals circulate more widely than most people realize.This new understanding underscores the need for both industry and individual vigilance to protect public health.[cbsnews+2]
