Sexually transmitted Shigella, a bacteria causing violent diarrhoea that can be fatal, is surging in the UK and has been labelled a 'public health threat' by experts. Cases linked to sexual contact reached 2,560 last year, according to the UK Health Security Agency (UKHSA). The disease is becoming increasingly resistant to antibiotics, a study by UKHSA and the University of Cambridge warns.
What is Shigella and How Does It Spread?
Shigella bacteria are typically found in faeces and contracted through contaminated food, touching contaminated surfaces, or close contact with an infected person. However, sexually transmitted strains have been rising steadily in Western countries since the 2000s, becoming endemic in some communities of men who have sex with men. Transmission occurs when a tiny amount of infected poo comes into contact with the mouth, for example through rimming or oral sex after anal sex.
Rapid Spread and Antibiotic Resistance
The study, published in The Lancet Infectious Diseases journal, found that sexually transmitted Shigella spreads more quickly than non-sexual strains. Sexual contact-linked strains averaged 72 miles (117 km) between cases, while non-STI strains reached just 28 miles (46 km). Professor Kate Baker, senior author from Cambridge's Department of Genetics, warned that due to increased antibiotic resistance, 'we're in a situation where it's virtually untreatable with drugs.'
Symptoms and Risks
Symptoms include diarrhoea, cramps, and fever. Unlike typical food poisoning, Shigella can last a week or longer and kills more than 200,000 people annually worldwide. Deaths can result from dehydration, intestinal perforation, or malnutrition. A person with Shigella can remain infectious for up to a month.
Public Health Recommendations
Professor Baker said: 'Sexually transmissible Shigellosis needs to be treated as a distinct public health threat, requiring different surveillance, prevention, and treatment strategies.' She urged people with stomach bug-like symptoms to avoid sex or going out to prevent spread. Typical advice such as handwashing and food hygiene is ineffective against sexual transmission, highlighting a gap in public health education.
How to Minimise Risk
- Wash hands, bottom, groin, and penis after anal sex.
- Change condoms between anal and oral sex.
- Use latex or non-latex gloves for fingering or fisting.
- Do not share sex toys or douching equipment.
Men who suspect they may have Shigella are advised to visit a sexual health clinic or GP for testing.
