There are many issues dog owners need to be aware of to ensure their pets can enjoy a happy and healthy life. These include diseases, many of which are potentially fatal, but preventable. A common problem for dogs in Hong Kong is heartworm ( Dirofilaria immitis), which is seen in most temperate and tropical zones around the world.
Kenda says he routinely conducts blood tests for heartworm, mainly when a dog has been on heartworm prevention but it has lapsed. "Most pet dogs now test negative for dirofilaria, compared with when I arrived in Hong Kong more than 20 years ago, when I diagnosed and treated many dogs for heartworm disease."
Thanks to client education and prophylactic treatment, the disease is now rare among his clients' pets. "However, like vaccinations, we should not drop our guard, because it is endemic in Hong Kong's wild dogs and, if ignored, it could return in increased numbers," Kenda says.
Heartworm refers to parasitic worms that reside in the dog's heart and lungs. These worms can grow up to 25cm long, Kenda says, and can cause an irritation to the lung tissue, and a physical occlusion (closure or blockage) in the heart chambers. "The blood cannot flow freely through the heart and lungs, and, therefore, the oxygen exchange capacity is reduced."
An infected dog will not show any signs of the disease in the early stages. However, an infection can be detected by a sensitive and specific blood test, Kenda says. As the disease takes hold, the dog will develop a cough and show signs of exercise intolerance. "As more and more worms grow, these symptoms worsen and there can be serious effects on the liver and other body systems," Kenda says.