What is it?

Cryptosporidium is a parasite that lives in the intestines of people, birds and animals. It produces cysts that can survive in the environment for a long time. The cysts are very tiny, only about 1/500th of a millimetre in size, so you won’t see them. When a person, bird or animal is infected they pass out the cysts in their faeces (poos).

It takes usually seven days (sometimes from 1 – 12) for symptoms to show after infection. Symptoms often come and go but resolve in less than 30 days. The symptoms are smelly, watery diarrhoea and stomach cramps. Lack of appetite, weight loss, fever, nausea and vomiting sometimes occur. Some people who are infected with cryptosporidium do not have any symptoms but they are still passing out the cysts in their poos. A poo specimen arranged by a family doctor will confirm if a person has cryptosporidium.

How does it spread?

Cryptosporidium is spread by hands contaminated with poos during toilet use or nappy changing. From hands it can spread to surfaces, toys, food and water. It can also spread by contact with infected animals, or in shared water such as swimming pools. When the cysts are swallowed the person then becomes infected.

Infectious period

People with cryptosporidium continue to be infectious for several weeks after the symptoms have stopped.

Exclusion period

Children can return when they have been free from symptoms for at least 48 hours. Careful attention must be paid to hand washing and hygiene during toileting and nappy changing as the cysts can still pass through the poos for several weeks.

Responsibilities of staff

  • Tell parents that a child at the centre has cryptosporidium.
  • Display information about cryptosporidium on your notice board.
  • Make sure all teachers, children and babies wash and dry their hands thoroughly after nappy changing and toileting before eating or handling food and infant formula bottles. Wash hands well after playing with animals - especially dairy cattle and calves. Uncooked foods such as fruit, crackers etc. can easily become contaminated by unwashed hands.
  • Make sure that children wash their hands after nappy change, and help children who cannot wash their hands properly.
  • If gloves are used for nappy changing extra care should be taken. Gloves are optional and not usually a hygiene advantage. A person wearing gloves will be less aware of soiled hands than a person with bare hands, and is at greater risk of contaminating the environment around them than a person with bare hands.
  • After a child who has been unwell with cryptosporidium has returned to the centre, their hand washing should be monitored as they may still be excreting cysts.
  • Provide good supervision of children during farm visits and make sure all children and teachers wash and dry their hands carefully after handling animals. Specific information regarding farm visits is available from Regional Public Health.
  • Clean all surfaces and toys with hot soapy water. Cryptosporidium is hard to kill with disinfectant, even bleach. Hot soapy water is more effective at removing the cysts.
  • Increase the frequency of toy cleaning. Rotate or put out fewer toys so that more frequent cleaning is manageable.
  • Wash smaller toys in the dishwasher.
  • Remove play-dough and water-play until there are no more cases of cryptosporidium.
  • Steam clean carpets if poos have contaminated them.

What to do when there are multiple children with the same symptoms:

  • Multiple cases is when there are three or more cases (staff or child), with the symptoms of vomiting or diarrhoea in a 48 hour period. Or four cases (staff or child) in seven days.
  • Call us if: o Numbers of sick children and/or staff doubled in a short timeframe.
    • Children and staff have bloody diarrhoea.
    • Children and staff have any unusual symptoms and/or pattern of disease.
    • A child has been hospitalised as a result of their illness.
    • You have concerns about the length of the outbreak or any other issues.
    • There was a party or event held at the centre during the time period of the illness.

Responsibilities of parents

  • Keep your child at home until they are well and have been symptom free for at least 48 hours.
  • Make sure all family members are washing and drying their hands properly. Use liquid soaps and dry thoroughly.
  • The child sick with cryptosporidium should not share towels with the rest of the family.
  • Children with cryptosporidium should not go swimming in a pool until two weeks after the symptoms have gone.
  • It is best practice to ask all parents to wash their hands when arriving at the centre. If this is not practicable, have adults use antiseptic alcohol-based hand sanitiser before entering or leaving the centre. Children and teachers should wash and dry their hands with soap and water on arriving and leaving the centre. Hand sanitisers are an addition to hand washing and should not be used instead of hand washing.


There is no specific treatment, but the doctor may prescribe some medication to relieve the symptoms.

Make sure children have lots of fluids as they are more likely to get dehydrated than adults. It is important to give them frequent, small drinks (consider using a syringe to give fluids).


Download printable factsheet

Last updated 14 July 2022.