Heartworm disease, as the name suggests, are worms that infect the heart. In Australia, the prevalence of heartworm disease is highest in subtropical/tropical areas (Darwin up to 100%, Brisbane 34%) and northern temperate areas (Sydney 25%). Dogs are the most important hosts, but cats may also be susceptible.
Heartworm (Dirofilaria immitis) in dogs is considered endemic in Australia, but the clinical heartworm disease caused by the heartworm is rare and prevalence is low.
There are many heartworm preventatives that are available for both dogs and cats, like Comfortis Plus. Prevention should begin at six to eight weeks of age. Some forms come in a chewable tablet or as spot-on application. There are tablets or spot-on application for cats as well to prevent heartworm.
Year-round prevention is best! Talk to your dog's veterinarian to decide which preventive is best for your dog. The American Heartworm Society advocates to “Think 12." Give dogs 12 months of heartworm prevention and get them tested for heartworms every 12 months.
All dogs are at risk, even those that are indoors only. Untreated, heartworm disease can result in severe heart damage and even death.
Signs of heartworm disease may include a mild persistent cough, reluctance to exercise, fatigue after moderate activity, decreased appetite, and weight loss. As heartworm disease progresses, pets may develop heart failure and the appearance of a swollen belly due to excess fluid in the abdomen.
With the three-dose adulticide protocol described above, in conjunction with doxycycline and macrocyclic lactones as recommended by the American Heartworm Society, 98% of dogs will be cleared of heartworm infection.
Because heartworms must be eliminated before they reach this adult stage, it is extremely important that heartworm preventives be administered strictly on schedule (monthly for oral and topical products and every 6 months or 12 months for the injectable).
Most of the monthly heartworm medicines have a safety factor of at least 15 days of protection if a dose is missed. This means that if you're just a week or two late, your pet is likely still within that window of protection and would be unlikely to become infected during that time.
A newer drug is available that does not have as many side effects, allowing successful treatment of more than 95% of dogs with heartworms.
Heartworm prevalence in Australia
Queensland and New South Wales are considered to be areas of higher risk whereas rates in South Australia are low (4,5).
Does my dog need heartworm medicine year-round? Yes, your dog needs heartworm medicine year-round. Just because mosquitoes may hibernate in the winter doesn't mean they're gone. And just because you live in a colder state doesn't mean your dog is safe either.
Proheart SR12 heartworm prevention yearly injection:
Up to 10kg – $111.50. Up to 20kg – $141.00. Up to 35kg – $186.75. Up to 50kg – $232.50.
Heartworm in dogs is prevalent across Australia and can be a serious and potentially fatal condition. Knowing how to prevent heartworm is essential for all dog owners. Luckily, there is plenty you can do to keep your pooch safe and healthy.
While the risk of heartworm is more prevalent in spring and summer when there are more mosquitos, a pet can get heartworm any time of year. In this blog, we will cover what heartworm is, how it spreads, and what the best ways are for you to prevent your pet from getting it.
Although there are fewer mosquitoes in the winter, there is still a risk that your pet could get heartworms if you stop giving heartworm prevention medication during this season. That's one reason veterinarians strongly recommend pets receive heartworm prevention medication year-round.
Heartworm preventatives can cause serious side effects in some dogs, including depression, lethargy, vomiting, anorexia, diarrhea, dilation of the pupil, loss of balance, staggering, convulsions, and hy-persalivation.
If you miss a dose of your heartworm prevention for your dog, get them back on prevention ASAP—speak to your veterinarian. Six months from that time that you missed is really the only time that we're going to be able to detect whether or not your dog was infected during that period.
The simplest answer to pet parents who forget a month of heartworm prevention is to simply give the pill or administer the application and restart their monthly preventative schedule.
Of course, these dogs can be given heartworm preventatives that do not utilize ivermectin (Revolution [selamectin] and Advantage multi [moxidectin] are both topical, so they treat fleas as well as prevent heartworm disease). Both of these medications are fairly new and will need to be purchased from your veterinarian.
Dogs with heartworm disease can live high-quality lives as long as they are given appropriate care. After completing treatment and following your veterinarian's recommenda- tions on heartworm disease testing and prevention, the chances of any long-term effects are very low.
The lifespan of a dog in this condition is most likely limited to a few weeks or a few months. Your vet will guide you on the best course of action for treating your dog depending on the severity of their infection. Dogs can live for at least six to seven months after becoming infected with heartworms.
Heartworm prevention
Puppies can begin heartworm preventative medication from as young as 6/8 weeks old. If your pup is a little older (age 6 months plus) it is important that she is given a heartworm test before preventative medication is given.
They're not visible. It's not like any worms that you could see in the poop or the stool, sometimes when dogs do have internal intestinal parasites, as this is one that lives in the bloodstream. The only way to really visualize them is with the use of imaging like x-rays or ultrasound.