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Its a topic that can send fear through a pet owner, heartworms. The largest problem with heartworms is that there is no vaccination, this is something that affects cats and dogs equally wherever there are mosquitoes and it is something that appears to be on the rise, especially in Florida. The Humane Society in Orlando reported an 80% increase in dogs with heartworms earlier this month. Below is a great video of the entire process from beginning to end. Please educate yourself and take care of your pet!


Heartworms disease?

Heartworms disease is a serious disease in pets. It is caused by foot-long worms (heartworms) that live in the heart, lungs and associated blood vessels of affected pets. Heartworms cause severe lung disease, heart failure and damage to other organs in the body. This disease affects dogs, cats and other warm blooded animals and—in rare instances—humans.


Heartworms in a dog

Dogs. The dog is a natural host for heartworms, which means that heartworms that live inside the dog mature into adults, mate and produce offspring. Heartworms disease causes lasting damage to the heart, lungs and arteries. Heartworms  affect the dog’s health. For this reason, prevention is by far the best option. Treatment—when needed—should be administered as early in the course of the disease as possible.

Cats. Heartworms disease in cats is very different from heartworm disease in dogs. The cat is an atypical host for heartworms, and most worms in cats do not survive to the adult stage. Cats with adult heartworms typically have just one to three worms, and many cats affected by heartworms have no adult worms. While this means heartworm disease often goes undiagnosed in cats, it’s important to understand that even immature worms cause real damage in the form of a condition known as heartworm associated respiratory disease (HARD). Moreover, the medication used to treat heartworm infections in dogs cannot be used in cats, so prevention is the only means of protecting cats from the effects of heartworm disease.

How did it get to into my pet?


The Heartworms Cycle

The mosquito plays an essential role in the heartworm life cycle. We have more than our fair share of the mosquito in NE Florida. Adult female heartworms living in an infected warm blooded animal produce microscopic baby worms called microfilaria that circulate in the bloodstream. When a mosquito bites and takes a blood meal from an infected animal, it picks up these baby worms. These worms develop and mature into “infective stage” larvae over a period of 10 to 14 days.

When the infected mosquito bites another available animal, the infective larvae are deposited onto the surface of the animal’s skin. The larvae enter the new host through the mosquito’s bite wound. Once inside a new host, it takes approximately 6 months for the larvae to mature into adult heartworms. Once mature, they can live for 5 to 7 years in dogs and up to 2 or 3 years in cats. Because of the longevity of these worms, each mosquito season can lead to an increasing number of worms in an infected pet. The mosquito is the enemy here because it is the superhighway for this problem.

What are the signs of heartworms in dogs and cats?

The heartworm is an item that grows inside the dog, based on the blood stream, so you probably will not see this in their stool, different part of the dog’s internal system. 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. Where are Heartworms more prevalent in the United States?

Dogs with large numbers of heartworms can develop a sudden blockages of blood flow within the heart. Blockages lead to a life-threatening form of cardiovascular collapse. Symptoms shown are a sudden onset of labored breathing, pale gums, and dark bloody or coffee-colored urine. Without prompt surgical removal of the blockage, few dogs survive. The worms just seem to grow and try and expand the size of the dog. Once they have taken over, they need to be removed by surgery. Then that is no guarantee because they are in the blood, inside the entire pet.

What can I do to protect my dog, now, before Mosquito Season starts?

Mosquito season seems to last all year here in Florida. The mosquitoes are around and new ones always seem to be taking the place of the old ones. Prevention options include a pill, a spot-on topical medication or an injection. All approved medications work by eliminating the immature (larval) stages of the parasite. This includes the infective heartworm larvae deposited by the mosquito.

In as little as 51 days immature heartworm larvae can molt into an adult stage. Heartworms must be eliminated before they reach the adult stage. Heartworm preventives must be administered strictly on schedule. Monthly for oral and topical products and every 6 months for the injectable. Administering prevention late can allow immature larvae to molt into the adult stage.

All preventative items must be administered by a Veterinarian. So get your dog checked at the vet for heartworms, because the Heartwormsmosquitoes do not care, and they are always here. Now is the time to check your dog, or with the annual exam. Heartworms do not have to be a scary part of your pet’s life. Take the necessary precautions now to make sure your pet remains healthy with you.