By Darryl Austin

As cases of urinary tract infections grow, infections are also getting harder to treat with commonly used antibiotics.

Urinary tract infections, or UTIs, are on the rise—and they may be becoming more dangerous. The overall disease burden associated with UTIs has increased by more than 68 percent between 1990 and 2019. At the same time, the bacteria that cause UTIs have developed resistance to common drugs.

Usually, UTIs are thought of as more of a painful nuisance rather than dangerous or fatal. But for an elderly patient or someone with multiple medical conditions, the antibiotics that fight the infection can be essential. Failing to get these antibiotics contributes to the deaths of hundreds of thousands of people every year globally. Even when they aren't deadly, the more than 400 million annual worldwide UTI cases significantly strain limited medical resources.

"We know UTIs are a tremendous cause of morbidity and even mortality, but they are also a huge burden on the U.S. healthcare system—contributing to well over $2 billion annually in healthcare costs," says Michelle Van Kuiken, a urologist and a urogynecologist at the University of California, San Francisco.

Working to ease this burden, scientists have been seeking to identify and understand lesser-known contributing factors. One culprit may come as a surprise: meat contaminated by Escherichia coli bacteria.

What Are UTIs And How Dangerous Are They?

UTIs can start in any part of the urinary system and can affect the kidneys, bloodstream, and uterus, but they most commonly infect the bladder "with symptoms of urinary frequency, urgency to urinate (sometimes despite having an empty bladder), and burning during urination," says Craig Comiter, a urologist at Stanford University. Cramping, fever, malodor, and blood in the urine can also be signs of a bladder infection.

UTIs occur when bacteria enter the urethra and infect the urinary tract—something that can occur during sexual activity, because of a genetic predisposition, or due to poor hygiene practices such as not wiping properly.

UTIs are the most common infection treated outside of hospitals in the United States, affecting some 50-60 percent of women during their lifetime. Roughly a quarter of women also report repeat infections within six months.

While UTIs can happen to anyone, they are about 30 times more common in women because females have shorter urethras that are closer in proximity to the anus—a common source of bacteria. Broken down, "the groups at most risk for infections are sexually active women, elderly women, and immunosuppressed men and women," says Comiter.

When UTIs only affect the bladder, they aren't considered dangerous and usually resolve without treatment—though antibiotics are frequently prescribed to speed the healing process up from weeks to days. When these infections spread to the kidneys, bloodstream, or to different areas of the reproductive system, however, they can lead to serious complications such as blood poisoning, sepsis, kidney damage, or kidney failure.

When left untreated, "a very small percentage of these cases can even be life-threatening," explains Jacob Lazarus, an infectious disease physician at Massachusetts General Hospital and a bacterial cell biologist at Harvard Medical School.

Why Are The Number Of UTIs Increasing?

The increasing number of UTI cases are due to several factors, one of which is a burgeoning population. "As the population increases, we expect more UTIs and more [of the disease burden associated with] UTIs because there are more people," says Lazarus.

On top of that, some of the conditions associated with UTIs, such as kidney stones and type 2 diabetes, are also on the rise. And a high number of teens and adults are sexually active. "In otherwise healthy women, sexual activity is the number one contributor to developing a UTI," says Van Kuiken.

The global population is also getting older. "Because UTIs are more common in seniors, their prevalence is increasing as the population ages," says Comiter.

Cindy Liu, a microbiologist and the chief medical officer at the Antibiotic Resistance Action Center at George Washington University’s Milken Institute School of Public Health, cites another compelling factor behind the rising numbers of more dangerous infections: an increase in antibiotic-resistant UTIs. "Without changing how we use our antibiotics, we are on track to have fewer options for treating bladder, kidney, and urosepsis infections," she says.

The Part Meat Plays

Meat consumption plays a part in all this in two distinct ways: by introducing infection-causing bacteria to the urethra, and because many of the antibodies introduced through meat sources end up increasing resistance to the medications that could kill the infection once it begins.

Healthy farm animals in the U.S. and elsewhere often receive antibiotics for disease protection, a practice known to drive antibiotic resistance. Comiter cites "the overuse of these antibiotics in animal husbandry" as one significant reason more and more people are developing resistance to the antibiotics used to treat UTIs.

"Eating meat that has been heavily treated with antibiotics may be contributing to increasing rates of antibiotic resistance as the human microbiome is being influenced by meat consumption," echoes Van Kuiken. "This does not mean that if you eat meat, you are going to get a UTI, but it could increase the likelihood that you may end up colonized with a multi-drug resistant organism."

Drug-resistant or not, E. coli from meat can colonize your gut and spread to your urinary tract. This can occur in women after the contaminated meat passes through the digestive system and is excreted in close proximity to the vaginal wall, where the bacteria has only a short distance to travel between the anus and the entrance of the urethra.

While scientists have long known this can happen, they're learning that it likely happens more frequently than previously suspected. A 2023 study estimates that contaminated meat causes nearly half a million UTIs in the United States annually—a small fraction of the more than eight million UTI-related healthcare visits in the country each year, but enough to merit concern.

Especially so because "30 to 70 percent of our retail meat products have been shown to be contaminated with E. coli," says Liu, who co-authored the 2023 research.

Such bacteria are usually killed in the cooking process before being ingested, she explains, so many of these infections are likely stemming from behaviors related to food preparation. "Unless you are extremely careful, you contaminate your sink, kitchen surfaces, your hands, and your raw foods whenever you handle contaminated meat products," says Liu.

From those places, the bacteria can proliferate, potentially coming into contact with the food you end up consuming.

How To Avoid UTIs

Avoiding a UTI—foodborne or otherwise—begins with good hygiene.

Because of the contamination danger, one important step is to take precautions when handling any meat products—specifically, chicken, turkey, and pork as they are more commonly associated with E. coli-related infections. Safe handling practices included washing hands frequently with soap and warm water for at least 20 seconds, cleaning and sanitizing food preparation areas and utensils after each use, and cooking meat to a safe temperature.

Liu says you can also reduce your exposure to drug-resistant E. coli by choosing to buy meats that are labeled as "USDA Organic," "Raised Without Antibiotics," "Animal Welfare Approved," "American Grassfed," or "No Antibiotics Ever."

To avoid other causes of urinary tract infections, Comiter suggests frequent handwashing, wiping from front to back after going to the bathroom, drinking adequate amounts of water, and urinating after sex as "efficacious ways to minimize the risk of infection."

When it comes to avoiding the worst outcomes of UTIs, he says, it's best to see your physician if you notice any concerning symptoms of infection or if symptoms seem to worsen. "If there is a fever or changes in mental status—which is more common in the elderly,” he explains, “then a more serious infection may be occurring, which may require hospitalization and a longer course of treatment.”

With proper precautions and care, Lazarus notes, the worst outcomes of urinary tract infections can often be avoided: "UTIs are quite treatable if diagnosed early."