Heartworms are parasites transmitted to dogs by mosquitoes carrying infective larvae. Once inside a canine host, the worm larvae travels to the heart and lungs, where it can grow up to a foot long and reproduce. The longer a dog is infected, the more worms ...

Worms in dogs are similar in many ways to parasites of other animals. They will cause illthrift and poor performance and they may result in intestinal issues such as diarrhoea and in rare severe cases even blockages. However, there is an even bigger concern with canine worms - they can cause serious health problems in humans.