Summer crypto surge leaves New Zealanders under the weather

The nasty faecal parasite Cryptosporidium has created a stink for many New Zealanders this summer, with higher than usual numbers struck down by the stomach bug in recent months, prompting public health warnings.

Cryptosporidium (or ‘crypto’) is a parasite found in the gut of infected people and animals that can cause smelly, watery diarrhoea and stomach cramps. It is passed on in the faeces (poo) of infected humans and animals. People become infected when they swallow the parasites, usually in contaminated drinking water, or in shared water such as swimming pools. It can also spread by contact from infected people or animals – including cattle, sheep, dogs and cats. It can also spread from infected people’s hands, to surfaces, toys, food and water.

Dr Susan Jack, National Clinical Director for Protection at Health New Zealand | Te Whatu Ora, said that since the beginning of the year to 8 March, 262 cases of crypto had been notified to public health services across the motu – more than three times the average of 81 cases for the same time period over the last five years – prompting reminders about the importance of good hygiene.

“There is currently no suggestion of a major cluster or concentrated outbreak, or any link to contaminated drinking water (which caused last year’s Queenstown outbreak). But what we can say, is that in approximately half the cases where information is available, those who became unwell with symptoms had been involved in swimming-related activities – with the majority of cases overall happening in urban areas, particularly within the Auckland, Canterbury and Waikato regions.

“These cases highlight the importance of people avoiding using swimming pools, splash pads, rivers, lakes and beaches for at least 14 days after they’ve had diarrhoea or other crypto symptoms – as well as keeping up with the other public health advice, including good hand hygiene to prevent spreading the bug to others.

“This means washing your hands with soap and water for at least 20 seconds and drying them thoroughly with a clean towel every time you go to the bathroom and before preparing food. Good hand hygiene is also important after contact with animals, after gardening, when caring for someone with diarrhoea, and when caring for a baby or changing nappies.”

Crypto is a common cause of acute diarrhoea in children, so it’s especially important children are kept home if they’re unwell and also know to wash their hands regularly.

“To stop the infection spreading amongst tamariki, you should keep children home for at least 48 hours after having diarrhoea. Parents and carers should also wash their hands thoroughly after changing a child’s nappies, and also wash the hands of the child.”

Swimming areas can also be a cause of illness if they are contaminated by sewage or animal faeces. To avoid getting crypto, people should check water quality monitoring warnings before jumping in the water. Land Air Water Aotearoa (LAWA) has information for the whole country, while those in the Northern Region can visit www.safeswim.org.nz to check local water quality.

Anyone experiencing severe illness, difficulty maintaining adequate fluid intake or long-lasting diarrhoea should seek health advice. If you have these symptoms contact your usual healthcare or hauora provider or call Healthline for free anytime on 0800 611 116.

A similar increase in crypto cases has also been reported recently by Queensland, New South Wales and Victorian health authorities. The recent warmer weather and increased levels of swimming in recreational water have been identified as contributing factors.

The National Public Health Service has increased disease surveillance across the motu to closely monitor crypto notifications and the spread of the disease.

There is no risk from public drinking water supplies.