Cryptosporidiosis fact sheet

What is cryptosporidiosis?

Cryptosporidiosis is an infection of the bowel caused by the parasite Cryptosporidium.  It is usually diagnosed by testing a faecal specimen that has been sent to a laboratory. Cryptosporidiosis is a notifiable disease.

What are the symptoms?

Symptoms can include watery diarrhoea and stomach cramps.  Fever, vomiting and loss of appetite may occur. 

In most people symptoms usually last for several days but sometimes can come and go for up to four weeks.  

Some infected people might only have a very mild illness or no symptoms at all.

Symptoms can develop between one to 12 days after becoming infected, usually within seven days.

People with weak immune systems (e.g. people on steroid therapy, chemotherapy, and those with HIV) may have may have severe and prolonged diarrhoea. 

Anyone can get cryptosporidiosis, although very young children, the elderly, people with weak immune systems and people who work with farm animals are at greater risk of infection.

How is it treated?

People usually recover from cryptosporidiosis within a few days and without antibiotic treatment.

Antibiotics are not routinely recommended for the treatment of cryptosporidiosis.

Anyone with diarrhoea should drink extra fluid to avoid dehydration. Children with diarrhoea who refuse extra fluids should see a doctor. Anyone with prolonged or severe diarrhoea or who has symptoms causing them concern should see a doctor.

Medicines to prevent vomiting or diarrhoea should not be given (especially in children) except when specifically prescribed by a doctor.

How is it spread?

The Cryptosporidium parasite is excreted in the faeces of infected humans and animals (cows and other domestic animals).  The parasite needs to be swallowed by a person to cause infection. 

People who have cryptosporidiosis can infect others while the Cryptosporidium parasite remains in their faeces. They may carry the parasite for several weeks and people can still spread the infection even though they appear well. The risk of infection decreases markedly after the diarrhoea has stopped.

Transmission can commonly occur from young children to other children or their carers. 

Young children in close contact with each other (for example in childcare facilities) may be at greater risk of infections. Spread can occur when children share toys or food that have been contaminated and placed in their mouths. Carers can become infected by changing the nappies of a young child with cryptosporidiosis.

Infection can also occur from drinking or swimming in contaminated water and through contaminated hands, objects or surfaces. 

The Cryptosporidium parasite is relatively resistant to chlorine and disinfection and therefore can be spread through contaminated swimming or wading pools.

How is it prevented?

Prevention measures for cryptosporidiosis include:

• washing hands in warm soapy water after going to the toilet, changing nappies, changing soiled linen, after gardening and after touching pets and other animals
• never changing nappies on tables or counters where food is prepared or eaten
• cleaning books, toys, equipment, furnishings, floors, nappy change areas and toilets regularly (including toilet door handles)
• not consuming unpasteurised milk.

People with diarrhoea should not prepare or handle food that will be eaten by others.

People should avoid drinking water from rivers, creeks, lakes and dams as Cryptosporidium may be in these water sources from contamination by wild or farm animals.

If untreated water is the only available source, it should be boiled for one minute before drinking or using in food preparation. 

Do not rely on filters as only some filters will remove the parasite. Chemical disinfection of water contaminated with Cryptosporidium is not effective.

How is it controlled?

Children in childcare or school should stay at home until they have not had a loose bowel motion for 24 hours.

People with cryptosporidiosis should not swim, wade or paddle in public pools or other recreational water facilities for at least two weeks after their symptoms have ceased.

People with diarrhoea who are involved in food preparation or care for others in hospitals, aged care facilities or childcare should not work while they are ill and should not return to work until 24 hours after their symptoms have ceased.  After recovery from cryptosporidiosis, it is important to maintain good hygiene and handwashing practices.

Population Health Services can support the response to outbreaks of diarrhoea.

If there are two or more cases in a hospital, childcare centre, aged care facility or other institution call the Population Health Services Hotline on 1800 671 738

October 2014

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