Heartworm in dogs – an unusual but
dangerous and incurable disease.

Despite this parasite having virtually all of Spain as it's habitat – in the Málaga province its absence has been more or less constant in the last years. In the last 5 years I have heard only of a few cases of dogs succumbing to the disease in the Málaga-San Pedro-Coín area. But now the disease has yet again blossomed – in Málaga there are now approximately 20 dogs that have been confirmed infected. The reasons for this sudden blossom can be numerous. The prevention of the spread of the disease is fairly simple, but once it has broken out it is very difficult to treat and as of August 2011 there is no longer any available medicine for heartworm.

Large areas of southern Spain and virtually all of Portugal belong to the area where heartworm exists. Due to this prevention should be a common practice.


Simple to prevent.
Prevention of the spread of heartworm is simple – one pill a month provides your pet with an effective shield against the disease. Heartworm is a disease that is spread by the parasite Dirofiliaria Imminitis and it is the common mosquito who spreads it. The blood of an infected dog contain microfilariae which stays in the area of the mosquito's mouth. The next step in the infectious process occurs when the mosquito bites another dog – thus spreading the parasite. Around 190 days later the microfilariae have developed into adult worms who in turn breed more microfilariae. The dog can now infect new mosquitoes who spread the disease.

A spaghetti-like appearance.
The fully grown heartworm reaches a maximum length of 25-30 centimetres (9.8" – 11.8") and it bears an appearance that resembles that of cooked spaghetti. The worm mainly resides the the pulmonary artery but, in connection with severe infections, can also be found in the right ventricle of the heart. The clinical symptoms vary depending on the degree of infection. As long as the number of worms is low, the dog can exhibit few or no signs of infection, but when the amount of worms increase the dog's general condition begin to deteriorate. If the disease is severe the dog shows signs of acute heart disease. It is relatively common that young dogs who show signs of heart disease have been infected with heartworm. On the other hand it is very unusual for cats to contract the disease. Humans cannot get infected.

Difficult to treat.
In areas where the disease exists, prevention is extremely important. If a dog is infected it will get severely ill. The treatment of a clinically ill dog is not only unpleasant, but can also be threatening the dog's life. It is easy to imagine the passage of events when a handful of dead spaghetti-like worms have decayed and have to be removed from the heart and on to through the rest of the body. They pass through the blood vessels and on to the body tissues. The risk of thrombosis (blood clots) in an organ is therefore very big.

A new problem has also arisen when the only pharmaceutical company who produce Immiticide, which is used to treat heartworm, have suspended it's production indefinitely. This means that it is currently not possible to treat a dog with heartworm. At worst this could lead to a pandemic because infected dogs indirectly infect others dogs via mosquitoes.

Continuous prevention.
The preventive treatment consists of feeding your dog one pill a month. This treatment is to be commenced 1 month after arriving in Spain and additionally one month after leaving the country. A simple blood-sample can be used in determining whether or not the dog has been infected. If the dog has stayed in the worst affected areas – Portugal, Cadiz and Alicante – it is wise to test your dog before commencing the preventive treatment.

Susanne Kamu
Clinica Veterinaria Pet Vet Kamu
C/. Maestra Aspiazu, Puebla Lucia, ES-29640 Fuengirola (Málaga) Spain.
Tel: (+34) 952 667 333, contact@petvetkamu.com
Copyright © 2006 - 2018 Clinica Veterinaria Pet Vet Kamu, all rights reserved.