What is the issue
Cryptosporidiosis is a parasitic disease that most commonly causes gastroenteritis. Since January 2013, there has been a substantial increase in Cryptosporidium notifications, While initially focussed on southern and eastern metropolitan Melbourne, an increase in notifications is now affecting Melbourne’s northern and western region. The organism lasts for long periods in water and the environment and is not destroyed by regular chlorination. In this outbreak there appears to be a role for transmission related to swimming pools and the key priority is the identification and prevention of further cases through hygiene measures at pools, childcare facilities and in household settings where there are cases. The Department is working with pool managers to ensure effective measures are in place to address the issue.
Who is at risk
All people can become infected and the risk appears to be greatest for those exposed to swimming pools or for those who are household contacts of cases.
Although most illness is mild and self-limiting, certain groups are more at risk of severe illness if infected, and these are younger children, pregnant women and individuals with weakened immune systems, especially HIV/AIDS – these individuals are at serious risk of prolonged and life-threatening illness.
Symptoms and transmission
The most common presentation is gastroenteritis, with symptoms including watery diarrhoea, cramping abdominal pain, bloating, vomiting and fever. Less commonly, Cryptosporidium infection can present as pneumonia, cholecystitis or pancreatitis.
After exposure it can take up to 12 days to develop symptoms, which then last between 4 to 21 days. Individuals are potentially infectious from the onset of symptoms until two weeks after becoming asymptomatic.
Transmission occurs by the faecal-oral route (person to person and animal to person), and via ingestion of contaminated water or foods.
Prevention and treatment
Clinicians are requested to maintain a heightened awareness of the possibility of Cryptosporidium infection and when considered, to take the following actions in addition to standard treatment advice focused on hydration:
- Enquire about potential exposures including swimming pools in the two weeks prior to onset;
- Send a stool sample requesting testing for Cryptosporidium;
- Advise the patient or their parent (if relevant) about the importance of hand hygiene measures and if relevant advise exclusion from childcare settings until 24 hours free of symptoms;
- Advise exclusion from swimming pools until 14 days free of symptoms; simple steps on preventive measures to reduce the risk of cryptosporidium contamination are available at http://health.vic.gov.au/water
Cryptosporidiosis is a Group B notifiable disease and requires notification by fax, online or in writing within five days.
Written notifications can be made: