Heartworms cause serious problems for dogs. Many pet owners have dogs with early stages of heartworm disease and don’t know it. Heartworm disease can be prevented and often cured in dogs but is fatal if left untreated. Pet owners should have their dogs tested for heartworm disease annually whether or not they are already on preventative medication.

What is heartworm disease?

Heartworms are a parasitic worm transferred to mammals through mosquitos. Although several mammals can contract the parasitic worm, dogs, wolves, coyotes and foxes are ideal hosts for the disease as the worm can mature into adulthood and reproduce inside their bodies. Ferrets are also susceptible to a fatal case of heartworm disease. Cats, and in rare cases even humans can contract heartworm disease, but most of the worms die before reaching adulthood making them less of a threat to the heart, lungs and other internal organs.  

How does heartworm disease spread?

Mosquitos are the only known transferring hosts of heartworms. While a mosquito is feeding on the blood of an infected animal with advanced stages of the disease, it ingests baby worms, or microfilaria living in the infected animal’s blood stream. After about two weeks, these baby worms have reached a level of maturity where they are infectious. Once a mosquito bites a susceptible host; it transmits the infectious larvae onto the skin of the animals which makes its way into the puncture wound left from the mosquitos bite and infects the animal. If your dog is on heartworm prevention medication, the larva typically dies quickly without causing harm. If your pet is not on heartworm preventative medication, the heartworm can live years without being detected. Then, as the worm grows and reaches adulthood, it starts causing serious complications.

What are heartworm symptoms?

Because heartworms can live up to 7 years, the symptoms are dependent on the stage of infection and the amount of worms an animal has.

    Stage 1 – No symptoms present other than the occasional cough

    Stage 2 – Occasional cough and abnormal tiredness

    Stage 3 – A cough, tiredness, and some trouble breathing. Signs of heart and or lung damage are usually seen on a chest x-ray at this stage.

    Stage 4 – Heartworms have caused severe damage to the animals heart, lungs, liver, and kidneys. In this stage, Caval syndrome is likely. Caval syndrome is when there is such a large amount of worms blocking blood flow to the heart that it creates a sudden life-threatening problem in need of quick surgical intervention. At this point, most dogs do not live long enough to receive the life-saving surgery.

Can you treat heartworm disease?

Heartworm treatment for dogs is possible, but treatment is costly and hard on your pet’s body. It typically requires many vet visits, blood work, x-rays, hospital stays and multiple medications. There is no drug approved to treat heartworm in cats. That said, cats that test positive for heartworm have a better prognosis as they are not ideal hosts for the parasite. The best thing for you to do for your pet is to prevent heartworms from ever developing.

Heartworm prevention is the best treatment

Dogs and cats should get on heartworm prevention medication starting as young as possible and no later than two months old. Dosage is based on body weight so most puppies and kittens can receive heartworm preventives as early as their first check-up. Every US state has reported heartworm infections, so every dog and cat in the US is at risk of coming into contact with the disease. There are three types of preventive options, but a veterinarian must prescribe them all. Heartworm prevention can be received through:

1.    Monthly heartworm prevention pills

2.    Monthly topical solution

3.    Bi-annual preventative injections   


Next steps for a healthier pet:

If your pet is not currently on a heartworm prevention regimen or you are more than two weeks late on administering your monthly heartworm preventative, than consult with your veterinarian or make an appointment today.  



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Here's a vet that still cares.
Just wanted to say I love Dr. Petcu's staff and his compassionate , caring way of taking care of my dogs.The staff is not only friendly and professional ,they know who you are when you arrive ,and they actually love animals. Is the first Animal Hospital that my dogs are at ease and feel comfortable.The place is very clean and the reception area very elegant and inviting. Exquisite services and Dr. Petcu always take his time to explain the disease and options and still finds time to play with my dogs. He's always treated both his animal and human patients with compassion and dignity,and would never recommend procedures unless he truly feels your pet will benefit from it. One of the vets that cares for your pet. The prices are reasonable and the services exceed all expectations. I Highly recommend Dr.Petcu and his hospital.

Reba S

Western Animal Hospital AMAZING! Western Animal Hospital is the best place in the valley .The staff is professional, friendly, caring and accommodating. The hospital is very clean and upscale. The customer service and the provided services are outstanding.Dr. Petcu is one of the most professional veterinarians that i have ever met in my 25 years of pet parenting. I drive across the valley just to see him( i live in Anthem) .He really cares about his animal patients and it shows in every visits . He is very knowledgeable , compassionate, friendly and always takes the time to answer any question i have and explaining in detail any situation we are dealing with. I had my share of visits to many animal hospitals in the valley but none of them had the last technology as Western - digital X-ray ( they send you home with a cd for you x-ray records ) every room has a computer monitor where the x-ray shows and Dr. Petcu can review with me every detail of it. Also they have the laser surgery and digital dental x-ray. Dr. petcu is one of the most
courteous and pleasant Vets I have ever met. The prices are more than reasonable and also they try to accommodate everybody. I cannot recommend them enough. You can rest easy knowing your pets are in their care.I STRONGLY RECOMMEND THIS HOSPITAL - THEY HAVE A CUSTOMER FOR LIFE IN ME! very good !

Betty K

Western Animal Hospital this doctor is making a lot of sense and will explain everything in details..
prices are great ....

.the best vet I met !! Pam M. 5 Western Animal Hospital - we are bringing our pets to Dr Petcu for 8 years. He was always helpful, many times we did not have the funds to treat our pets but he was fine with us paying when we had the money. He saved our cats in many instances and all I have to say is that I greatly reccomend Western Animal Hospital for any responsable pet owner .

Yolanda M

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