Health Authorities Issue A Serious Warning Over A Multidrug Resistant Shigella Outbreak
South Australia Health is urging men who have sex with men to be aware and cautious after identifying a drug-resistant strain of the bacterial infection shigella. Case numbers are higher now than at the same time last year.
What is Shigella?
Shigella is a highly contagious bacteria that causes a bowel infection. Symptoms include vomiting, stomach cramps, bloody and severe diarrhoea, fever and nausea. They typically appear between 12 hours and four days after exposure and can last up to a week. In most cases, rest and fluids are enough. When symptoms become severe, antibiotics are necessary.
That’s where this particular outbreak gets complicated. The strain now circulating is multidrug-resistant (MDR), meaning the usual oral antibiotics simply don’t work in some cases. When that happens, intravenous antibiotics administered in hospital become the required course of action.
Why the numbers in 2026 matter
Between 2023 and 2025, South Australia averaged around 196 shigella infections per year, with a small proportion of those involving drug-resistant strains. Five MDR cases were recorded among gay, bisexual and other men who have sex with men (GBMSM) across all of 2025. Since January 2026, six cases of the same strain have already been confirmed in that same group.
“Shigella is highly contagious, and even a small number of bacteria can cause infection,” SA Health told QNews. “Some strains of Shigella develop resistance to antibiotic treatment, increasing the risk of poor outcomes.”
SA Health’s Communicable Disease Control Branch (CDCB) is monitoring the situation closely and working alongside SAMESH (South Australia Mobilisation and Empowerment for Sexual Health) to get the word out through targeted health promotion.
How does it spread?
The bacteria enter the body through the mouth after contact with the faeces of an infected person. Transmission can happen through direct contact, contaminated food, water or surfaces, and through certain types of sexual activity. It only takes a small amount of bacteria to cause infection, and a person remains infectious for up to four weeks from the onset of illness.
What to do if you think you’re infected
If symptoms develop, see a doctor and mention any recent sexual activity or close contact. Rest and hydration are the starting points. Avoid anti-diarrhoea or anti-nausea medication unless a doctor specifically advises it.
Handwashing remains the most effective preventive measure. Wash your hands thoroughly after using the toilet, before handling food, and after close physical contact. Keeping shared spaces clean also reduces the risk.
It’s worth knowing this stuff. If you’re in South Australia and want support or more information, SAMESH provides free and confidential sexual health services, including resources for the broader LGBTQIA+ community.
