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Have A Heart Campaign

Our Have a Heart campaign is to raise much needed funds and awareness for our Heartworm Disease Program. 

What is Heartworm Disease?

Heartworm disease is a serious and potentially fatal disease in pets in the United States and many other parts of the world. It is caused by foot-long worms (heartworms) that live in the heart, lungs and associated blood vessels of affected pets, causing severe lung disease, heart failure and damage to other organs in the body. Heartworm disease affects dogs, cats and ferrets, but heartworms also live in other mammal species, including wolves, coyotes, foxes, sea lions and—in rare instances—humans. Because wild species such as foxes and coyotes live in proximity to many urban areas, they are considered important carriers of the disease. More on this below!


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. If untreated, their numbers can increase, and dogs have been known to harbor several hundred worms in their bodies. Heartworm disease causes lasting damage to the heart, lungs and arteries, and can affect the dog’s health and quality of life long after the parasites are gone (if left untreated for a long period of time). For this reason, heartworm prevention for dogs is by far the best option, and treatment—when needed—should be administered as early in the course of the disease as possible. 


Treating heartworm disease is a lengthy and expensive process but relatively routine. 

  1. An initial blood test is done that detects the presence of adult worms.

  2. If positive for heartworm disease, a second blood test is sometimes done to detect microfilaria (early stage worms) in the bloodstream. 

  3. Sometimes an ultrasound of the heart is required if the dog is believed to have had heartworm disease for a lengthy period of time and this will help determine whether to complete the short treatment or the long treatment. 

  4. The dog is put on antibiotics and a steroid for 30 days prior to treatment.

  5. After the 30 days, an injection of Immiticide is given in the dogs spine. 

    1. For short treatment, this injection is given again 24 hours later.​

    2. For long treatment, this injection is given one month later and then again a day after the second.

  6. The dog now has to go on pain medication and be monitored for 24 hours after the injections.

  7. The Immiticide goes to work in killing the heartworms. 

  8. Exercise has to be restricted after the injections. No running at all. Immiticide causes the heartworms to die off and move through the bloodstream. If the dogs blood pumps too fast, there is a risk of a heartworm becoming lodged and this is often fatal.

  9. Heartworm prevention has to be given on a monthly basis during this process to make sure no other heartworms can hatch. 

  10. A blood re-test is done 3 - 6 months after the final injection. It can take up to 8 months to get a negative result.

  11. If still positive after the 8 months, the process re-starts. (Rare)

Paws Crossed's Heartworm Disease Program:

Paws Crossed is dedicated to helping dogs affected by heartworm disease - but we need your help! We take around 50 dogs per year that are either heartworm positive and untreated, or positive and already treated but not re-tested yet. 

These dogs will go into foster homes where they can rest comfortably in a home during their rest and treatment periods. This also means that Paws Crossed is responsible for any other medical issues that may come up in the 6-8 months that they are in foster. 

Treatment for each dog that is heartworm positive ranges

between $500 and $1,500 each.

Donate today to help a heart in need.

HW info

How is Heartworm Disease Spread?

The mosquito plays an essential role in the heartworm life cycle. Adult female heartworms living in an infected dog, fox, coyote, or wolf 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, which develop and mature into “infective stage” larvae over a period of 10 to 14 days. Then, when the infected mosquito bites another dog, cat, or susceptible wild animal, the infective larvae are deposited onto the surface of the animal's skin and enter the new host through the mosquito’s bite wound. Once inside a new host, it takes approximately 6 months for the larvae to develop into sexually mature adult heartworms. Once mature, heartworms 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.

Signs of Heartworm Disease:

In the early stages of the disease, many dogs show few symptoms or no symptoms at all. The longer the infection persists, the more likely symptoms will develop. Active dogs, dogs heavily infected with heartworms, or those with other health problems often show pronounced clinical signs.

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. Dogs with large numbers of heartworms can develop a sudden blockages of blood flow within the heart leading to a life-threatening form of cardiovascular collapse. This is called caval syndrome, and is marked by a sudden onset of labored breathing, pale gums, and dark bloody or coffee-colored urine. Without prompt surgical removal of the heartworm blockage, few dogs survive.

All information is from the American Heartworm Society.

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