Matenga yersinia Yersinia

Yersiniosis is a bacterial infection that can cause acute stomach illness. It is rare in Aotearoa New Zealand. Yersiniosis is not usually serious and most people recover quickly. It is caused by infection with 'Yersinia pseudotuberculosis' or 'Yersinia enterocolitica'.

Symptoms of yersiniosis

If you have been infected it usually takes 5 to 10 days for symptoms to show. It can take up to 21 days. The bacteria can still be present in poos weeks after the symptoms have gone.

Symptoms include:

  • runny poos (diarrhoea)
  • stomach cramps 
  • vomiting 
  • fever. 

Yersinia pseudotuberculosis

Symptoms of 'Yersinia pseudotuberculosis' include:

  • abdominal pain — often on the lower right — which may mimic appendicitis
  • fever
  • runny poos (diarrhoea)
  • rash and joint pain, appearing 1 to 3 weeks later — joint pain can last up to 6 months.

In rare cases it can cause and infection in the blood (sepsis). This is more common in people with weakened immune systems.

Yersinia enterocolitica

Symptoms of 'Yersinia enterocolitica' vary between younger tamariki, older tamariki and adults. For tamariki under 5, symptoms include:

  • runny poos (diarrhoea)
  • vomiting
  • fever
  • abdominal pain.

The most noticeable symptom in older tamariki and adults is abdominal pain. People who have a weakened immune system (immunocompromised) can get very unwell.

When to seek medical advice

You should see your healthcare provider if:

  • you have prolonged or severe diarrhoea
  • you have symptoms that concern you.

You should take your tamaiti (child) to your healthcare provider if:

  • they are not drinking
  • they are passing less wee (urine) than usual
  • they have a dry mouth or sunken eyes

they seem drowsy.

How yersiniosis spreads

Yersiniosis is spread by:

  • contact with infected poo
  • eating or drinking contaminated water
  • contact with contaminated soil
  • contact with infected animals, especially pigs.

Foods that have been known to cause outbreaks include:

  • pork
  • raw grated carrots
  • lettuce
  • contaminated milk.

Diagnosing yersiniosis

If you think you have yersiniosis contact your healthcare provider. They will take a sample of your poo and send it to a lab to test.

Treating yersiniosis

Yersiniosis is not usually serious and will go away on its own. Sometimes, your doctor may prescribe you antibiotics.

Most people recover quickly. If you have diarrhoea you should drink extra fluids to avoid dehydration.