Escherichia coli is one notorious species of bacteria. While many strains of E. coli are harmless, some strains cause nasty infections that range from mild to deadly. They can cause stomach cramps, vomiting, bloody diarrhea, pneumonia, meningitis and many more.

But one unique strain has piqued the interest of researchers. In the early aughts, this E. coli single-handedly caused several antibiotic-resistant urinary tract infections (UTIs) across the United States. This is surprising because UTIs are not contagious — they do not cause outbreaks.

So, how could that have happened? According to researchers from the University of California, Berkeley, the superbug might have spread through contaminated food.

The link between antibiotic-resistant UTI and food

In the early 2000s, the researchers were studying urine samples from college students with UTI. The students hailed from three different universities across the United States: one in California, one in Michigan and one in Minnesota. Yet the same strain was responsible for 38 to 51 percent of the antibiotic-resistant UTIs.

“We were really surprised to find so many unrelated women with UTIs caused by the same organism,” said Amee Manges, lead author of the study.

Dr. Lee Riley, an infectious disease expert and the principal investigator of the study, explained that UTIs are not considered epidemic infections. The bacteria that cause UTIs can travel between people but the disease itself is not contagious.

Instead, you get a UTI when germs present in your gut relocate and proliferate in your urinary tract — that is, your ureters, kidneys, urethra and bladder. This can happen during sex. Bacteria living in the bowels, like E. coli, can travel from the anus to the urethra during anal penetration. Meanwhile, vaginal sex can push bacteria on the skin into the urethral opening.

Because of this, the researchers suspected that the women acquired the superbug from contaminated food.

“We’re trying to explain why this particular strain of the E. coli would be found in three different places in the U.S.,” Riley said. “The conclusion we made was maybe [the bacteria] was spread by some contaminated food product.”

Past studies seem to suggest that too. In 1970, British researchers looked for the presence of E. coli in hospital food, hospital kitchens, meats delivered to hospitals, slaughterhouses and poultry-packing stations. They found the bacteria everywhere they looked.

The researchers concluded that E. coli can be transmitted to humans by ingesting contaminated food. They also hypothesized that the use of antibiotics for farm animals may produce drug-resistant E. coli in the human gut, which can result in antibiotic-resistant UTIs.

But the idea that UTIs are foodborne did not gain much traction until three decades later — when UTI outbreaks were already plaguing those three universities.

Regulating antibiotic use to curb the spread of drug-resistant E. coli

In the ensuing years, Riley has conducted more studies about the link between contaminated food and UTIs. In 2018, she and her team found more than 90 distinct genotypes of E. coli in meat samples from California. Twelve of these cause UTIs.

Still, the federal government refuses to monitor the spread of uropathogenic (bacteria found in the urinary tract) E. coli like other foodborne pathogens. Because of that, experts have less information at their disposal and have a harder time monitoring and responding to outbreaks. Because of that too, using antibiotics for livestock isn’t strictly regulated, which could lead to more antibiotic-resistant strains of E. coli.

Meanwhile, drug-resistant UTIs are growing. In 2019, the New York City Department of Health found that a third of UTIs caused by E. coli are resistant to first-line antibiotics sulfamethoxazole and trimethoprim, commonly marketed as Bactrim, while a fifth are resistant to five other common treatments. Those numbers are staggering considering that around seven million doctor visits are for UTIs and many of those are caused by E. coli.

That’s concerning because UTI is a gateway disease that can lead to more advanced forms of life-threatening antibiotic-resistant infections, according to Riley. That’s why it’s important to monitor the rise of drug-resistant UTIs.

For its part, the Food and Drug Administration has started collecting E. coli samples from meat, according to Steven Roach, food safety director of Food Animals Concerns Trust (FACT). But the FDA has yet to reclassify uropathogenic E. coli as foodborne.

Roach hopes to see that decision made so that the use of antibiotics in livestock will be tightly regulated. This, in turn, can curb the spread of superbugs like E. coli and the rise of antibiotic-resistant UTIs.

Sources:

FoodRevolution.org

Berkeley.edu

MedicalNewsToday.com

NICHD.NIH.gov