Cryptosporidiosis

At a glance

No vaccine available – read more about prevention
Nationally notifiable disease

About cryptosporidiosis

Cryptosporidiosis is a disease caused by the parasite Cryptosporidium.

The parasite can live in the intestines of people and animals.

Most people with cryptosporidiosis get diarrhoea and stomach cramps, but some can develop serious complications, especially if they are immunocompromised.

Why it matters to public health

Cryptosporidiosis is a major cause of gastroenteritis worldwide.

In Australia, infections are most common in children aged under 10 years.

The parasite can survive in chlorinated water, and contaminated water can cause outbreaks. In Australia, outbreaks of cryptosporidiosis have been associated with:

swimming pools
spas
water play areas
early childhood education and care centres
petting zoos and farms.

Because of this, we:

work with the animal and environmental public health sectors to ensure a coordinated One Health approach to share information, monitor and report on cryptosporidiosis in Australia
plan for how to manage outbreaks.

Symptoms

If you’re looking for advice about your own health or treatment options, see healthdirect or speak with a qualified healthcare professional. Our role is to provide public health advice – information and guidance that helps prevent disease, protect communities and improve wellbeing at a population level.

Symptoms can include:

More serious complications can include:

severe, long-lasting diarrhoea
liver and bile duct problems.

Most people will get better within about 1 to 2 weeks. But some people may relapse and get symptoms again.

healthdirect’s symptom checker can help you decide whether to see a health professional.

Check your symptoms

Onset of symptoms

Symptoms usually start about 7 days after getting infected. But this can range from 1 to 12 days.

How it spreads

Cryptosporidium is found in the stool of infected people and animals, including farm animals, pets and wildlife.

People can get infected if the parasite enters their mouth through:

close contact with someone who has cryptosporidiosis, especially young children
swimming in contaminated water, like pools, spas and water play areas
touching infected animals or their stool
sexual activity
contaminated food or drink, including unpasteurised milk
touching contaminated surfaces and then touching their mouth.

Infectious period

People are most infectious while they have diarrhoea but can spread the parasite for weeks after their symptoms stop.

Prevention

Protect yourself

There is no vaccine against cryptosporidiosis.

The best protection is to maintain good hygiene and frequently wash hands well with soap and water for at least 20 seconds, especially:

after going to the toilet
after changing a nappy or caring for someone with cryptosporidiosis
after contact with animals or their stool
after gardening
before preparing, handling or eating food.

Hand sanitiser is not effective against Cryptosporidium. Soap and water must be used for hand washing.

It is also important to:

try not to swallow water when swimming
avoid swimming in natural waters for at least 3 days after heavy rain
wash raw fruits and vegetables carefully
not drink unpasteurised milk.

Protect others

People with cryptosporidiosis should not:

swim in public aquatic facilities for at least 2 weeks after diarrhoea stops
share towels or bed linen for at least 2 weeks after diarrhoea stops
prepare food for others for at least 48 hours after diarrhoea stops
have sexual contact while they have symptoms.

Children with cryptosporidiosis should not attend early childhood education and care centres until they have had no diarrhoea or vomiting for at least 24 hours.

Read more ways to prevent cryptosporidiosis.

Priority groups and settings

Anyone can get cryptosporidiosis, but some people are at greater risk of getting it or getting very sick.

Cryptosporidium spreads more easily in countries with lower water quality and sanitation. People should know the risks for where they are going before they travel and take steps to protect themselves.

People at greater risk of severe disease

Cryptosporidiosis poses a greater risk of severe illness for people who are immunocompromised.

People at greater risk of exposure

People are at greater risk of being exposed to Cryptosporidium if they live with or provide care for someone with cryptosporidiosis.

The risk might also be greater for people who:

work at or attend early childhood education and care centres
swim regularly in public aquatic facilities
drink unpasteurised milk
work with animals – especially farm animals
may have contact with stool – including through sexual contact
travel to countries with poor sanitation or lower food handling standards.

Diagnosis and treatment

Cryptosporidiosis is diagnosed through a stool test.

You can use healthdirect’s directory to find a health service near you.

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Most people with cryptosporidiosis will get better within 2 weeks without specific treatment. Treatment is supportive, including drinking plenty of fluids.

People with severe or long-lasting diarrhoea might be prescribed medicine.

Read more about how to manage or treat cryptosporidiosis.

Surveillance and reporting

Cryptosporidiosis is a nationally notifiable disease – these are diseases that present a risk to public health.

Health authorities in each state and territory report new laboratory confirmed cases to us daily through the National Notifiable Diseases Surveillance System.

The OzFoodNet network also monitors and responds to foodborne diseases in Australia.

We take a One Health approach to cryptosporidiosis surveillance activities. We work with other government agencies to help us monitor case numbers around the country and understand disease patterns.

We analyse the data and report on case numbers and other data through our data visualisation tool, where you can filter and search the latest information.

Outbreaks

How public health agencies respond to cryptosporidiosis outbreaks depends on:

state or territory laws and reporting requirements
the nature of the outbreak
what resources are available.

Managing these outbreaks can require major public health action, such as:

closing facilities
issuing public warnings
cleaning to stop further spread.

Actions public health authorities might take include:

educating people about cryptosporidiosis
closing facilities so they can be decontaminated
making sure facilities and businesses are compliant with regulations and infection prevention and control measures
issuing alerts to let people know about the risks, such as when there are contaminated waterways or floodwaters
issuing alerts to boil drinking water.

Read more about how the Australian Government defines and plans for outbreaks.

Support

For information about cryptosporidiosis in your state or territory, see:

If you need mental health support, see a list of organisations, websites and services that offer support, counselling and information.

For travel advice, see Smartraveller.