The 'Flesh-Eating' STI You Probably Don't Need to Worry About

Donovanosis is an infection caused by the bacterium Klebsiella granulomatis. Based on information available, the disease seems to spread primarily through sexual contact, Russo said.

"There's some rare reports [of] perhaps transmission independent of sexual activity, but that they're not well validated," he added. "So we really think of [it] as a sexually transmitted disease."

An infected person may first notice papules—small raised bumps—appearing in the genital area, usually sometime between a few days and a month after sexual contact. Occasionally, symptoms may show as late as a year after infection.

Over time, donovanosis can produce "fairly large" beefy-red ulcerative lesions, Russo said. The ulcers are painless but bleed readily to the touch, according to a 2002 paper by researcher Nigel O'Farrell in the British Medical Journal.

Whether the disease is truly flesh-eating depends on how loosely you define the term. Lesions can eventually cause permanent scarring and tissue damage, as well as infection and other complications if left untreated, though donovanosis progresses slowly relative to some other ulcerative diseases, Russo noted.

Luckily, donovanosis is both treatable and curable, according to the U.S. National Library of Medicine. Treatment involves a course of antibiotics administered for about three weeks or until the ulcers are gone, along with follow-up appointments to see if the disease reappears.

Russo emphasized that people in Northern global regions have little to fear from this disease. In "middle- [to] high-income, non-tropical geographically located" countries, case numbers remain near negligible and mostly limited to people who have traveled to tropical regions recently and their sexual partners.

In the United States, there are about 100 cases of donovanosis per year, according to the University of Florida Health. Exact numbers are more difficult to pin down, because there's no mandated reporting for donovanosis cases to state health bodies or the Centers for Disease Control and Prevention (CDC), according to Ina Park, a professor at the University of California, San Francisco (UCSF) School of Medicine and co-author of the 2021 CDC STI Treatment Guidelines.

Still, there's good reason to believe the disease is extremely rare in the U.S. and staying that way.

"I've been working in an STI clinic for 14 years and have never seen a case, and my veteran colleagues have seen one or two cases in their whole careers," Park said. "There's no reason to think there has been a sudden uptick in cases."

For people in the global North concerned about bedroom threats, there are far greater risks, Russo said. For example, the number of cases of syphilis—a sexually transmitted disease that, if left untreated, can erupt into an array of nauseating ulcerative symptoms—rose from 2,646 in 2010 to 7,900 in 2019 in the U.K., according to Public Health England.

In the poorer countries where donovanosis is more common, the data can be murky, but based on the information available, other STIs and STDs such as chlamydia, herpes, syphilis and HIV appear to present a more significant problem to the population of those nations, Russo added.

There have been times when donovanosis cases rose to epidemic levels. The largest recorded outbreak was observed in Papua New Guinea from 1922 to 1952, when 10,000 cases were identified among a population of 15,000, according to O'Farrell's paper. Another significant outbreak occurred in South Africa during the late 1980s and '90s, when 3,153 cases were observed, mostly around Durban.

None of this is to say that donovanosis isn't a serious problem for people unlucky enough to catch it or that anyone with symptoms should delay treatment. Russo advised people who have STI symptoms, including those associated with donovanosis, to avoid sticking their heads in the sand and seek testing and treatment as soon as possible.

"I appreciate that people sometimes may be embarrassed or feel a sense of shame or are concerned about privacy-related issues," he said. "But procrastination or 'ostriching' is not a good strategy here."

Any ulcers or other types of lesions below the belt are a good reason to schedule a doctor's appointment. Russo said it's important to remember that not all ulcers in the genital region are sexually transmitted, and doctors would also perform a biopsy to rule out the possibility of cancer.

Safer sex is always the right choice, whether you're worried about rare tropical diseases or not. But for now, people in the global North don't have much to fear from donovanosis. Given current case numbers, your risk of catching donovanosis is far lower than it is for other STIs. It's another case where the hype around a disease has spread much farther and faster than the infection itself.