You get infected when you swallow the Shigella bacteria. This can happen when you:
- eat food that has been contaminated or poorly handled – flies and other insects like cockroaches can transfer the bacteria to food
- have contact with poo from a person that has shigellosis – this can happen if hands are not washed properly after going to the toilet or changing nappies
- drink untreated water – animals can contaminate water collected from roofs, bores, creeks, lakes and streams
- swim in contaminated waterways
- engage in some types of sexual activity (oral–anal sex).
You can infect other people while the Shigella bacteria is in your body and poo. This is usually for a month from when diarrhoea starts.