Cat poo and swimming pools—how to avoid nasty parasite infections

In the lead up to National Science Week 10 to 18 August 2024, the Food Safety Information Council is warning Australians about the risk of parasites with increasing numbers of toxoplasmosis and cryptosporidiosis infections.

The Council's Director, Professor Shokoofeh Shamsi, said a recent study by Food Standards Australia New Zealand and the ANU found there were 15,500 cases of toxoplasmosis in Australia each year. Infection with Toxoplasma is very risky for pregnant women and their babies as well as people with compromised immune systems where it can cause blindness and stroke.

"While only 17% of Australians say they have heard of toxoplasmosis, 25% to 30% show signs of past Toxoplasma infections One common way people get an infection is via cats. Toxoplasmosis may cause blindness and stroke and it can also occur through eating raw or rare sheep, pork, kangaroo or game meat, as well as offal such as heart, liver, and tongue, or duck and goose paté. Game meat can also be infected by Sarcocystis, which is a close relative of Toxoplasma gondii," Professor Shamsi said.

"There are three simple ways to reduce your risk of Toxoplasma gondii infection:

1. Safe pet care. Toxoplasmosis is transmitted by domestic and feral cat feces, so clean out cat litter trays daily and always wash your hands thoroughly after cleaning. If you are pregnant or immune compromised, get someone else to do this or wear rubber gloves. Don't feed your cat raw red meat and try to keep cats out of areas where you are preparing food, especially kitchen benchtops. As always, wash your hands with soap and dry thoroughly before handling food and after handling your pet, their food or toys. Don't let your pets lick or take food from your plate. Don't wash pet food bowls in with your own dishes; preferably wash them in a separate laundry sink if you have one.
2. Cook your meat to the safe temperature. The parasites can reside as cysts (like eggs or seeds) in the muscle tissue of raw or undercooked meats and this is the most common way people get infected. We recommend you use a digital meat thermometer and cook whole pieces of red meat such as lamb, to at least 63°C (medium rare) and leave to rest 3 to 5 minutes. Cook pork whole cuts and pieces to 70°C and roasts to between 70°C and 75°C and leave to rest 3 to 5 minutes. Minced products should be cooked to at least 75°C. The Toxoplasma gondii parasite isn't frequently found in beef or kangaroo meat.
3. In the garden. If you grow your own fruit and vegetables, fence or cover your gardens to make sure your pets or wild animals can't poop where you are growing food. You might want to use gloves when gardening in case you come into contact with animal feces and always wash your hands thoroughly when you have finished. Don't forget to secure and cover children's sandboxes when they are not in use, to deter cats from using them as makeshift litterboxes.

"There has also been a fourfold increase in the numbers of gastro-causing cryptosporidiosis with 11,747 reported cases in 2024 compared with 3,716 in 2023. A quarter of all cases are in children under four and most are in Queensland, possibly because the weather is warmer and people can swim most of the year.

"Cryptosporidiosis is caused by microscopic parasites in the feces of infected domestic animals, farm animals and humans. It's spread by swimming in contaminated water, through contact with an infected person, or by drinking unpasteurized milk or dairy products. The parasite cysts (eggs) are not killed by chlorine."

You can reduce your risk of Cryptosporidium infection by:

1. Washing your hands thoroughly. Do this before handling food, after going to the toilet or changing nappies, after gardening and after touching pets and farm animals or handling their feces/manure or, if you have been infected, for at least 48 hours after your diarrhea has stopped.
2. Staying home. If you or your child has diarrhea don't go to work or send your children to school or daycare as diarrhea is highly contagious.
3. Not swimming. Don't enter a swimming pool or spa if you have diarrhea or until two weeks after symptoms have ended. You may still be shedding cysts, which are resistant to chlorine. Don't swim in rivers, creeks and dams during and for at least three days after heavy rain, or swim in the ocean during and at least one day after heavy rain.
4. Not preparing food for others and not sharing towels or linen for at least 48 hours after your diarrhea has stopped.

"If you or your child have persistent gastro contact your doctor or call Health Direct," Professor Shamsi concluded.