ECDC warns of growing spread of multidrug-resistant Shigella in Europe

Since 2023, more than 2 300 infections linked to seven genetically distinct MDR/XDR Shigella sonnei and Shigella flexneri clusters have been reported by countries in Europe as well as the United States. The clusters include both long-standing and more recently identified transmission chains and are associated with mainly, but not exclusively, gay, bisexual, and other men who have sex with men.

The growing circulation of MDR/XDR Shigella strains is a public health concern because treatment options are becoming increasingly limited. At the same time, the bacteria can spread very easily between people, including through sexual contact.

Shigellosis is an intestinal infection that commonly causes diarrhoea, stomach cramps and fever. Most infections are mild and 

resolve without antibiotics, but severe illness can occur, particularly in immunocompromised individuals. Traditionally associated with food- and waterborne outbreaks, Shigella transmission reported to ECDC has increasingly involved sexual transmission in recent years. Several of the circulating strains now carry resistance markers to multiple first- and second-line antibiotics used to treat shigellosis. A particular reason for concern at this time is the upcoming travel season, Pride events and festivals which may increase the likelihood of transmission across Europe.

The Centre is encouraging healthcare professionals to consider sexually transmitted Shigella in patients with gastroenteritis symptoms, ensure antimicrobial susceptibility testing when antibiotic treatment is required, and report cases to public health authorities. ECDC is also calling on countries to strengthen microbiological surveillance and genomic sequencing to help detect potential outbreaks and monitor the spread of resistant strains.

To reduce the risk of infection and onward transmission, ECDC advises people to avoid sexual activity if they have diarrhoea or gastrointestinal symptoms, maintain good hygiene, and seek medical care if symptoms are severe or persistent.

Notes

• Shigella spreads through the faecal–oral route, including during oral–anal sexual contact.
• Infection can occur after exposure to only a very small number of bacteria.
• MDR Shigella refers to strains resistant to two or more antibiotics.
• XDR Shigella refers to strains resistant to all five antibiotics commonly used for first- and second-line treatment: azithromycin, ciprofloxacin, ceftriaxone, trimethoprim-sulfamethoxazole, and ampicillin