How Do Dogs Catch Heartworms and What Are the Risks

Dogs catch heartworms through the bite of an infected mosquito, which injects the larvae into the dog's bloodstream.

The larvae then migrate to the dog's heart and lungs, where they mature into adult heartworms over the course of several months.

Heartworms can grow up to 12 inches long and live in the heart and lungs, causing damage and disrupting normal blood flow.

Mosquitoes become infected with heartworms when they feed on the blood of an infected animal, such as a dog or a wild animal.

Dogs of all ages and breeds can get heartworms, but puppies are more susceptible due to their immature immune systems.

Broaden your view: Lifespan of a Dog with Heartworms

It's essential to start heartworm prevention early in a puppy's life. For puppies, heartworm prevention can begin from 8 weeks of age.

HEARTGARD PLUS is a great option for chewable heartworm tablets that not only protect against heartworms but also hookworms and roundworms.

NexGard SPECTRA for Dogs is a top choice for combined heartworm and flea prevention, along with protection from mites, ticks, and intestinal worms.

For maximum protection, it's crucial to give your dog the right heartworm prevention medication at the right age.

Heartworm disease is a serious condition that can be fatal if left untreated, and it's essential to understand how it affects dogs. Heartworms are parasitic roundworms that live and reproduce in a dog's heart and blood vessels.

These worms are transmitted through mosquito bites, which carry the immature form of the parasite Dirofilaria immitis. Once bitten, the dog becomes infected with the parasite larvae, which eventually enter their bloodstream.

The life cycle of this parasite requires a dog species, as dogs are the definitive hosts for this parasite. Although heartworms can be found in other mammalian species, they cannot complete their life cycle without a dog.

Dogs, cats, ferrets, and non-domestic canids can get heartworm disease, and it has been diagnosed in all 50 states and can occur worldwide. However, its prevalence can vary depending on climate and seasonality, with a higher risk in warmer climates and during warmer months.

Here are some key facts about heartworms:

Dogs are the definitive hosts for heartworms, meaning they're the only species where the parasite can complete its life cycle.

Heartworms live in the blood vessels of dogs, not in their intestinal tract. This is a common misconception that can lead to ineffective treatment.

Dogs can get heartworm disease from mosquito bites, which transmit the immature form of the parasite Dirofilaria immitis.

Here are some interesting facts about heartworms in dogs:

Dogs can get heartworms from mosquitoes that have previously fed on an infected dog.

Mosquitoes are the primary carriers of heartworms, and they can transmit the parasites to your dog through a single bite.

Indoor dogs are not immune to heartworm disease, as mosquitoes can easily fly into your home and bite them.

Adult female heartworms in an infested dog produce tiny juvenile worms called microfilariae, which are then picked up by mosquitoes during a blood meal.

These microfilariae develop into juvenile worms inside the mosquito, and can then be passed to a new dog when the mosquito takes another blood meal.

Heartworms can be up to 12 inches long, and they migrate to the pulmonary arteries on the right side of the heart.

Here's an interesting read: Can U Catch Worms from Dogs

Dogs get heartworms through a mosquito bite, when an infected mosquito transfers the microfilariae, a larval stage of the heartworm, to the new dog.

The microfilariae go through several stages in the mosquito, including the L3 stage, before being transferred to the new dog.

Only L3 and L4 larvae are killed by heartworm preventatives, making it crucial to administer the medication on time as prescribed.

It takes an additional 120 days for the heartworm to show up on a standard heartworm test, even after the vet has given the dog a heartworm test, and during this period, any doses of heartworm prevention will not be effective in killing the worms.

Dogs and humans can only get heartworms from infected mosquitoes, and the likelihood of coming across a positive mosquito increases dramatically with just one heartworm-positive dog in the area.

There are at least 70 species of mosquitoes that can ingest microfilariae, an immature stage of heartworm, when they feed on an infected animal.

Discover more: Heartworm Test

Here's a breakdown of the heartworm life cycle in dogs:

It's essential to start heartworm prevention for dogs as early as eight weeks old. This is because even puppies are exposed to mosquitoes, which can deposit baby worms into their skin.

You can start prevention as early as eight weeks old, but the first testing can be done at six months old. This is a good time to start prevention, especially since your first puppy vaccine appointment is a great opportunity to do so.

Starting prevention early is crucial because it prevents the disease from taking hold. Heartworm preventatives are designed to destroy the worms before they enter the bloodstream, which is why it's so important to start early.

NexGard SPECTRA for Dogs allows for heartworm prevention to begin from 8 weeks of age, ensuring your puppy is protected against heartworm from the get-go.

Recommended read: Can Dogs Catch Worms from Humans