Heartworm disease is a serious and potentially fatal disease seen in all mainland states of Australia. Dogs are more susceptible to heartworm infestation than cats, and heartworm disease also tends to be more severe in dogs. Adult worms live within the heart and large blood vessels where they can grow to more than 30 cm in length. Heartworm larvae, more commonly called microfilariae, can also be found circulating in an infected dog’s blood.

How is heartworm in dogs spread?

Heartworms are transmitted from one dog to another by mosquitoes, which pick up the tiny microfilariae when they bite an infected dog. The microfilariae develop in the mosquito and are transmitted when the infected mosquito bites another dog. The heartworm larvae then migrate through the dog’s tissues and circulatory system, eventually reaching the heart and lungs where they grow into adult heartworms.

Why is heartworm disease dangerous?

Heartworm may cause no clinical signs in the early stages of infestation, but as the worms grow and mature, they can interfere with the normal circulation of blood. This can result in signs of heart failure, and in some cases may lead to sudden death.

Thankfully, heartworm is very easy to prevent and should form part of your pet health care routine.

If your pet has not been on heartworm prevention we strongly recommend you speak to us about a heartworm test prior to starting a prevention program.

Please call us to discuss the best heartworm prevention program for your pet.

The most common ticks infesting dogs in Australia are the paralysis tick, the brown dog tick, and the bush tick.

Paralysis ticks

The paralysis tick lxodes holocyclus is one of the most dangerous parasites that can affect your pet. Tick paralysis is estimated to affect tens of thousands of dogs and cats per year in Australia, with many animals dying. The greatest risk is associated with high numbers of adult ticks in spring and summer, but disease can be seen throughout the year. Paralysis ticks are found on the east coast of Australia, from northern Queensland to Victoria.

How does the paralysis tick cause toxicity?

After the tick has attached to the host animal it sucks blood and then secretes a toxin that can cause severe illness, or even death, in cats and dogs. Dogs and cats of any age can be affected.

Signs of tick paralysis include: loss of coordination in the hind legs (wobbly or not being able to get up) which may progress to the front legs, change in bark, retching, coughing or vomiting, loss of appetite, or laboured or rapid breathing. Any of these signs may indicate the presence of a paralysis tick. If your dog shows any of these signs you should seek veterinary attention as soon as possible.

Tips for reducing the risk of tick paralysis include:

• The year-round use of effective tick control products for all dogs and cats that are living in, or travelling to, known paralysis tick regions.
• Search your dog daily for ticks – although tick control products will greatly reduce the risk of tick paralysis, it only takes one tick to cause tick paralysis. For this reason, it is important to also perform daily tick searches on your pet.
• Reduce exposure to ticks in the environment (e.g. clean up leaf litter and debris, minimise or restrict your pet’s access to bushy environments).
• If you find a tick, remove it immediately, and seek veterinary attention.

Brown dog ticks and bush ticks

Brown dog ticks and bush ticks do not cause tick paralysis, but they can cause skin irritation and also transmit other important diseases e.g. Babesia parasites which invade the red blood cells of dogs causing anaemia (which can be fatal).

We are more than happy to show you how to do a thorough tick search and recommend appropriate tick control products for your pet. Please call us to discuss.