Warning issued over large increase in cases of cryptosporidiosis in children

A large increase nationally in the number of cases of cryptosporidiosis in children since March, especially in children aged one to four years of age, has been detected by the Health Protection Surveillance Centre (HPSC).

Cryptosporidiosis can cause severe watery diarrhoea which may last for several weeks.

Public health doctors have found that many of the cases have occurred in children that had handled or fed lambs or calves.

In the past few weeks, there has been a large increase in cases of cryptosporidiosis around the country.

It is affecting children and young people, aged 1 to 19 years of age.

Since the beginning of March this year, the numbers of cases of this type of gastroenteritis (tummy bug) have been more than twice what they usually are, especially in small children aged 1-4 years of age.

With the government measures and restrictions that are in place to control and prevent the spread of COVID-19, schools have been closed - only opening last month.

It is thought that with children having been at home, many - particularly in rural areas - are spending more time outdoors than in previous years.

Moreover, many children from farming families may be spending more time than usual out on the farm, and children may be coming in contact with this bug because they are outside more.

What is cryptosporidiosis?

Cryptosporidiosis is an infectious gastroenteritis, caused by a bug called cryptosporidium.

People get sick and develop gastroenteritis when they swallow the bug. When an animal or person is infected, the cryptosporidium bug lives in the bowels and passes out in the stool.

The bug is very tough and can live with high levels of chlorine and warm water.

The chlorine levels in drinking water are not high enough to kill the bug – only filtration or boiling water is enough to remove or kill the bug.

Drinking water that is properly treated is safe, though.

What are the symptoms of Cryptosporidiosis?

The most common symptom of cryptosporidiosis is watery diarrhoea.

Other symptoms include:

Tummy cramps or pain

A temperature



Some people with cryptosporidiosis will not get sick at all.

Symptoms of cryptosporidiosis generally begin about a week after swallowing the bug, but can start after only a couple of days.

The symptoms last about one week (but can last longer).

People who are immunocompromised (whose body’s defence system is weak due to a medical condition or because of medication) can have severe symptoms if they catch cryptosporidiosis.

How is cryptosporidiosis spread?

When the cryptosporidium bug passes out of the person or animal in the stools or manure, anything contaminated by the stools or manure (hands, touch surfaces, handles, food, water and outdoor surfaces) can lead to a person swallowing the bugs and becoming infected.

Cryptosporidiosis can cause large outbreaks of gastroenteritis, especially if water supplies become contaminated.

Every spring we see a peak in cryptosporidiosis cases – this happens at the same time as the lambing and calving seasons, and means an increase in people having animal and environmental contact.

People, especially children, are more likely to get infected because there is so much more cryptosporidiosis in animal manure and in the environment.

How can I help prevent my children getting cryptosporidiosis?

The best way to prevent cryptosporidiosis is to regularly wash your hands (and your children’s hands) with soap under warm running water.

Hands should always be washed:

After using the toilet

Before eating

Before preparing food

After playing or being outside (especially on the farm)

After touching dirty outdoor clothes or boots

After touching your pets

It is important to know that:

Alcohol hand gel will not kill the cryptosporidum bug – only soap and warm water will.

Children should not eat food (including treats) out of doors especially on the farm, or in the open countryside, unless their hands have been cleaned.

Raw (unpasteurised) milk can be contaminated with many harmful infectious diseases including cryptosporidiosis. Young children and pregnant women are at most risk.

If you have a private well, you should ensure that the water from it is safe. The EPA has advice on protecting your well.

More details are available on the HPSC website.