Doctors issue warning as cases of sexually transmitted gut infection surge
A bacterial gut infection that can be transmitted through sexual contact is rapidly spreading in the UK. New research indicates that cases transmitted sexually are increasing at more than double the rate of other strains and are becoming more resistant to antibiotics.
Shigella is a bacterial infection that leads to severe diarrhea, stomach cramps, and fever. While most individuals recover within a week, the infection results in over 200,000 deaths globally each year, primarily due to dehydration, malnutrition, or intestinal perforation.
In England, there were 2,560 sexually transmitted cases of Shigella in 2025, an increase from 2,318 in the previous year and 2,052 in 2023.
What new research reveals concerning numbers
A study conducted by the University of Cambridge and the UK Health Security Agency examined over 3,500 Shigella samples collected in the UK from 2004 to 2020.
The findings showed that sexually transmitted strains spread more than twice as quickly in terms of distance compared to non-sexually transmitted cases, averaging 117 kilometers over two and a half years, while other strains averaged only 46 kilometers.
Shigella is spread through the fecal-oral route, meaning it moves from feces to the mouth. In the context of sexual transmission, this occurs through anal sex (either direct or indirect contact with fecal matter), rimming (oral-anal contact), which is considered the highest risk activity for this infection, and fingering followed by touching the mouth.
“Sexual infection is now a sustained part of Shigella transmission in the UK,” stated Professor Kate Baker, the senior author of the study, emphasizing that sexually transmitted Shigella should be regarded as a distinct public health threat that requires its own surveillance, prevention, and treatment strategies.
Doctors caution about these symptoms
Dr. Giuseppe Aragona, a GP and medical adviser, informed Tyla that symptoms usually appear within a few days of exposure and include sudden diarrhea, abdominal cramps, fever, and in some instances, blood or mucus in the stool.
He mentioned that if someone experiences ongoing diarrhea, symptoms of dehydration like dizziness or decreased urine output, or noticeable blood in the stool, it is crucial to see a doctor right away.
To minimize risk, he suggested washing hands frequently, particularly after using the restroom and before preparing food, ensuring safe food handling, and drinking clean water while traveling. Additionally, individuals who participate in anal sex or rimming should thoroughly wash their hands between activities.
For those who might have contracted the infection through sexual contact, he advised refraining from sexual activity until all symptoms have completely disappeared and maintaining good hygiene practices before and after engaging in sex.