Salmonella

Salmonella infection is a type of food poisoning that can cause runny poos (diarrhoea) and stomach cramps. Salmonella is caused by bacteria which live in the intestines of people, birds, and animals. When a person, bird, or animal is infected they pass the bacteria out in their poo (faeces). This can then contaminate food, drinking water and make you sick if you swallow or drink it.


How salmonella spreads

You are most likely to get salmonella from swallowing contaminated food or water.

You can also get salmonella poisoning from:

  • touching contaminated objects
  • eating under-cooked meat and chicken
  • handling raw meat and chicken contaminated with salmonella
  • eating raw or poorly cooked eggs
  • drinking raw (unpasteurised) milk
  • drinking water from rivers, streams, and shallow waters
  • not washing hands after touching animals and birds.

Symptoms of salmonella

Symptoms of salmonella can include:

  • runny poos (diarrhoea)
  • stomach pain or cramps
  • feeling sick (nausea) or throwing up (vomiting).

Symptoms usually start 6 hours to 3 days after you have caught it. The symptoms usually last between 1 to 7 days. In severe cases they can last up to 10 days.


Diagnosing salmonella

If your healthcare provider thinks you have salmonella, they will need a poo sample for testing.

The role of public health

Salmonella is a notifiable disease. This means healthcare providers or laboratories will inform public health when someone has it. This way we can:

  • monitor how many people are sick
  • contact people you have been in contact with and arrange for testing of their poo
  • give advice on how to reduce its spread.

Treating salmonella

Most people with salmonella can self-manage their recovery at home.

Contact your healthcare provider or call Healthline for free on 0800 611 116 if your symptoms are ongoing or become more severe.


Reducing the risk to others

If you have salmonella you should stay away from work, school or early childhood centres until 2 days after the symptoms have stopped.

Do not go swimming in a pool if you have runny poos. You need to wait until at least 2 weeks after symptoms have gone.

If you or a child are unwell then do not share bathwater, as this can easily spread the infection.

Wash your hands with soapy water for 20 seconds, then dry well with a clean cloth or paper towel every time:

  • after going to the toilet
  • before preparing food, eating or drinking
  • after changing nappies.

If you have symptoms, avoid preparing food for other people. If you must do so, wash and dry your hands well first.


Preventing salmonella

Food safety

Practice safe food preparation, cooking and storage, and avoid cross-contamination. More information is available on the Ministry for Primary Industries website.

Preparing and storing food safely at home (external link)

Safe drinking water

Avoid drinking water that has not been treated, including water from lakes, rivers or streams, or from an area where you do not know the quality of source water.

If you have to drink untreated water that is taken from a roof, river or lake, boil for at least 1 minute.