Fleas are one of the most problematic parasites, causing itching, discomfort, allergic reactions and carrying tapeworms.

Ticks range from the nuisance bush tick to the dangerous Paralysis Tick, common on the eastern seaboard, which can cause muscle weakness and respiratory distress from a single bite.

Intestinal worms (roundworm, tapeworm, hookworm) cause weight loss, vomiting, diarrhoea and anaemia.

Heartworm is transmitted by mosquitoes and can cause serious, even fatal, heart damage — prevention is recommended across most of Australia (Tasmania is lower risk).