Giardia is a tiny parasite that attacks the lining of the intestines and causes very watery, strong smelling diarrhoea.
Giardia spreads by infected poo, so can be caught anywhere infected poo particles lie i.e. infected water or food, infected dogs and the environment. Giardia germs can survive in the environment for months, even once the original poo particles have gone.
Humans can catch giardia so it’s important to wash your hands after cleaning up dog poo or meeting a dog with diarrhoea.