Urinary tract infections (UTIs) are among the most common bacterial infections worldwide, affecting more than 404 million people each year — especially women.1 They’re often blamed on hygiene habits or anatomy, but research has long pointed to another culprit: contaminated meat.
For years, I’ve reported that E. coli from animals raised in concentrated animal feeding operations (CAFOs) is a hidden driver of these infections. Now, new research published in mBio confirms what earlier studies have shown — that a significant number of UTIs are traced to the same bacteria found in store-bought meat.2 This strengthens the growing body of evidence that the problem isn’t just personal hygiene but a food supply saturated with antibiotic-resistant pathogens.
This matters because it redefines what “food safety” really means. It’s not only about proper cooking or refrigeration — it’s about the systemic use of antibiotics in industrial farming that shapes the bacterial landscape you’re exposed to daily. These findings reinforce what I’ve warned about since at least 2019: what’s on your plate directly influences your risk of infection.
Understanding how these infections begin — and what you can do to stop them — is the key to protecting your urinary and overall health.
E. coli from Meat Is Fueling the UTI Epidemic For the mBio study, researchers analyzed over 36,000 Escherichia coli (E. coli) samples collected between 2017 and 2021 across Southern California.
Researchers sequenced the bacteria from both human UTIs and retail meat to determine how many of these infections came from food animals. What they discovered was alarming — nearly 18% of UTIs were caused by zoonotic E. coli, meaning strains that jumped from animals to humans through contaminated meat.
The problem was worse in low-income neighborhoods, where infection rates rose above 21%.
• Most contaminated meat came from poultry and pork — Poultry was the primary reservoir for dangerous E. coli strains, but all retail meat was heavily contaminated. Chicken and turkey were identified as the top carriers, accounting for over 74% of the meat-linked UTIs. While pork and beef had high contamination rates (54% and 47%, respectively), their strains appeared less able to cause human infection.
Contamination rates were as high as 82% in turkey and 58% in chicken purchased from major grocery chains. Researchers confirmed these bacteria are extraintestinal pathogenic E. coli (ExPEC), which means virulent strains originating in food animals were entering the human food chain and establishing colonies in people’s urinary tracts and bladders.
• Zoonotic strains were genetically distinct, confirming cross-species infection — Genetic sequencing revealed that the bacteria responsible for these UTIs carried mobile genetic elements — small packages of DNA — that matched those found in livestock rather than humans. These genetic markers acted like fingerprints, proving that the infections weren’t random.
Once inside the human body, these animal-derived bacteria established colonies in the urinary tract and, in severe cases, progressed to the bloodstream. This finding challenges decades of medical assumptions that E. coli infections stem only from a patient’s own gut bacteria.
• Women and older adults faced the greatest risk of infection — Among the thousands of patients studied, nearly 90% were women, with a median age of 50. Women were more than twice as likely as men to contract zoonotic E. coli infections (19.7% versus 8.5%). Older men were also highly susceptible, with those infected tending to be in their 70s. These groups likely face increased risk due to hormonal, anatomical, and immune differences that make their urinary tracts easier targets for bacterial invasion.
• Socioeconomic inequality amplified the danger — Living in areas with higher poverty levels increased the odds of developing a zoonotic UTI by 1.6 times. The study linked this to several factors, including poorer food safety standards in lowcost retail environments, longer storage times for meat, and reduced access to clean cooking facilities.
In other words, people in poorer neighborhoods were being exposed to more contaminated meat and had fewer resources to prevent infection. The researchers warned that public health efforts need to address these environmental inequalities, not just personal hygiene.
• Antibiotic-resistant bacteria were found in both meat and humans — Many of the E. coli strains isolated from meat showed resistance to commonly used antibiotics, including ampicillin and tetracycline.
These same resistance patterns were found in human samples, suggesting that agricultural antibiotic use was transferring resistance genes into the human population. Even more concerning, some of these bacteria were resistant to multiple drug classes, limiting treatment options. When antibiotic-resistant infections occur, they often require hospitalization and stronger, more toxic medications.
Industrial Farming Practices Are the Underlying Cause
The overuse of antibiotics in animal agriculture is breeding stronger, more resilient bacteria. CAFOs, where thousands of animals live in cramped, unsanitary conditions, provide the perfect environment for pathogens to evolve. When meat from these operations reaches consumers, it carries those bacteria with it. Cooking destroys most but not all of them, especially if meat isn’t handled or heated properly. Over time, this exposure contributes to an invisible pipeline between CAFOs and hospital infections.
• E. coli from poultry carried the greatest risk of spreading from animals to people — The data showed that chicken and turkey were responsible for nearly three-quarters of the meat-linked UTI cases. Specific bacterial lineages appeared repeatedly in both meat and human infections. These strains came from bacterial families known to cause more serious infections. Interestingly, even though poultry had fewer of the classic “dangerous” E. coli lineages than beef or pork, its strains were better at surviving cooking and adapting to the human urinary tract.
• Genetic analysis revealed how these bacteria adapt and spread — The researchers trained a computer algorithm to identify whether a given E. coli genome looked more like one from a human or an animal. This allowed them to calculate how many infections came from food sources. They found that nearly 1 in 5 UTI samples in people had bacteria with animal DNA, while less than 1% of the meat samples showed any human-related bacteria. This proved that transmission was happening primarily from animals to people, not the other way around.
• Reducing antibiotic use in livestock could curb human infections — The researchers noted that after California passed Senate Bill 27 — limiting antibiotic use in farm animals — antibiotic resistance in both meat and clinical samples declined. Resistance to tetracyclines, for example, dropped from 50% in previous studies to just over 30%. This indicates that policy changes in farming practices directly influence public health outcomes. By cleaning up the meat supply, regulators could reduce the number of drug-resistant UTIs and other infections.