Trust Me, Don't Get Caught...

When you go to the Vet, they always tell you same thing and if you read the box the same thing is said, but many people make the same mistake and go against their better judgment and think that they are smarter than the scientist that poured countless of hours and millions of dollars into developing a product that will keep death away from your dog.
I am talking about something that hit very close to home with one of our dogs.  Doc was found to have heartworms on a routine test that was performed on our dogs this spring.  When the news came back, I was devastated, to say the least.  When I worked for a Vet, the chances were a lot slimmer that a dog would make it if heartworms were discovered.  I remember once asking the Vet I worked for why is it so bad and he said, “You poison the blood to kill the heartworms” and nearly the same thing is true today.  It has been refined some, but you have to kill the worms.  Dog get heartworms from mosquitos and I take every precaution because I don’t ever want to go through this again.  For nearly 3 months, Doc had to be kept quite and is not only is the treatment very dangerous it is also very expensive.  When we were just starting to go through it the treatment, as usual, I researched it and made many calls to the manufacture of the preventive medicine and to the maker of the treatment medication too.   

Purchase from a Vet or a reputable online pharmacy, not a discount supply house and you Must have a prescription.
Give the medication ALL year long.  Just because mosquitoes are not present, doesn’t mean they aren’t around.
If you are a standing customer and the dog had the yearly test, chances are the manufacturer will cover the cost of the treatment.
Give the medication ALL year long.  Just because mosquitos are not present, doesn’t mean they aren’t around.
 And the most important statement is if you don’t treat in the winter months you WILL NOT kill the microfilaria (newborn children of the adult heartworm) if they are infected and when you start back up in the spring, they have grown and will not be killed by monthly prevention.
My protocol has changed on treatment because of this,

Give EVERY month
Watch the dog when you give it.  Don’t let them go back to playing where they can throw up and lose the dose.  I put mine in the kennel for one hour so I can make sure it stays down.
Purchase from your Vet.  If you use a bargain treatment and it fails, the money you spent on treatment could supply all the dogs in the neighborhood. 

Heartworm Removal Video 

Below is some scientific info on the subject put together by Karen Newhall.  Please read it and trust me, it can happen and did here on the farm.

Heartworm Disease – what is it?
Heartworms (Dirofilaria immitis) are found in more than 30 species of animals as well as humans.  They have been identified in species such as coyotes, foxes, wolves, other wild canids, domestic cats, wild felids, ferrets and even sea lions, however, the dog is considered the primary host for heartworm, meaning that it is in the dog where the heartworm reaches maturity and is able to sexually reproduce.  Heartworm larvae (immature stage) are transmitted between hosts by mosquitos.  When a mosquito infected with heartworm larvae bites a dog, the larvae are transmitted into the dog’s blood stream and begin to migrate throughout the body while maturing.  They end up as sexually mature heartworms in the heart and lungs.  Here, they begin to reproduce and the females release offspring called microfilariae into the circulating blood supply of the host (your dog).  Heartworm cannot be spread between mammals without first going through the mosquito.
The initial population of adult heartworms living in a dog resides in the arteries of the lower lobes of the lungs.  As the population continues to grow and mature, adult heartworms can be found in the right chamber of the heart.  In cases with extremely high numbers of adult heartworms present, worms can be found in the caudal vena cava, which is the primary vein of the lower body.  When worms are present here, they must be removed surgically due to the likelihood of sudden death caused by an embolism which can occur within a few days.  The presence of worms in these major organs will cause inflammation in the heart, lungs and arteries around these organs.  The heart will begin to enlarge and congested heart failure will likely develop over time.  Dogs that lead a very active lifestyle such as working/herding breeds that are infected with heartworms will likely develop a more severe disease state with fewer heartworms present than a less active dog. This is due to the need for greater heart and lung capacity needed for an active lifestyle.
Heartworm Prevention – why and how
The best methods to ensure you and your dog never have to go through the devastating results of being heartworm positive; PREVENTION is truly the best medicine.  Dogs have been tested positive for heartworm infections in all 50 states.  There are many products on the market that are highly effective for the prevention of heartworm disease.  There are both oral and injectable products that have to be dosed daily, monthly or even every six months.  You should consult with your veterinarian on which product is best for your dog, ideally, your dog should be tested for heartworm disease prior to starting a preventative program.  Most prevention products currently on the market will effectively kill the heartworm larvae that are transmitted by mosquitos, therefore preventing mature heartworms to develop in the dog.
The most important part of administering heartworm prevention products is complying with the label directions given by the manufacturer of the product.  You should not only talk to your veterinarian but also carefully read the product insert so that you understand how the medicine should be given and potential adverse effects associated with the product.  Heartworm prevention is recommended to be done year round by most practitioners and the American Heartworm Society.  In most climates there can be mosquito hatches every month of the year and therefore your dog is at risk of being infected.  Additionally, some products will actually continue to prevent disease if you are late or even miss a dose provided you have reliably dosed your dogs on a monthly basis for at least three consecutive months, consider year round dosing an insurance policy in disease prevention for the life of your pet.
Heartworm testing – why, when and how
There are many thoughts and opinions on the frequency of heartworm testing dogs.  You should always follow the advice of your veterinarian; they are the trained professional and have an established relationship with your dog.  Generally, it is a good idea to have your veterinarian test your dog during your annual wellness visit to the clinic, but minimally, you should test your dog prior to initiating or changing preventatives.  If you missed one or more doses of heartworm preventatives during the year, it is imperative that you have your dog tested for heartworm the following year.
There are two types of heartworm tests available, one detects antigens and the second detects antibodies, both are simple blood tests.  The antibody test has been used for decades and detects antibodies that the dog’s body is producing in response to the presence of adult heartworms.  The antigen test is most commonly used now and detects a protein in the heartworm that causes an immune response in the body.  The antigen test can detect an infection of one or more mature female heartworms that are at least seven to eight months old.  They cannot detect infections of less than five months in duration.  A veterinarian can also test for the presence of microfilariae in the bloodstream of a dog, these will only be present if adult heartworms are also present and can be detected six to seven months after a dog is bitten by an infected mosquito.  This is due to the life cycle of the heartworm; a mosquito will pass the larvae into the bloodstream of the dog which then takes many months to develop into a sexually mature worm that is able to produce microfilariae.  This is why it is important to test your dog for heartworm annually, especially if you are not 100% certain that all doses of prevention were given at the same time of every month, year round.
There are four main phases in the lifecycle of a heartworm: microfilaria, larva, juvenile worm and adult worm.

Heartworm Positive – what and how
A positive heartworm test will determine that your dog was not only been bitten by an infected mosquito, but that sufficient time has passed and the heartworm larvae was able to develop into sexually mature worms over a period of 6-7 months.  It is possible for a dog to test positive to heartworm while on prevention products, this is because the preventative will only control larvae and not microfilariae or adults.  If you routinely stop preventative administration during the winter, larvae transferred from infected mosquitoes to your dog late in the season will have ample time to develop into mature and reproducing adult heartworms before you re-initiate your prevention program in the spring. 
Treatment for heartworm – what, how, why and risks
Your veterinarian will discuss treatment options with you along with associated costs and risks.  There is only one product available commercially for the treatment of adult heartworm infestations, Immiticide®, this compound is a form of arsenic and can have severe adverse side effects, it is not always readily available and it is expensive, however, it is the only treatment option available.  It is injected deep into the muscles of the lower back twice, 24 hours apart and typically repeated four months later. 
A secondary part of treatment that your veterinarian may consider is treating for Wolbachia infection.  Wolbachia is a genus of richettsial organism and is similar to a bacteria; they live inside of adult heartworms.  Wolbachia organisms are not fully understood, but they seem to provide a protective and beneficial effect for the adult heartworms.  Treating the dog with the antibiotic doxycycline will kill Wolbachia and seem to also sterilize the female heartworms, preventing them from reproducing.  Wolbachia is also thought to be involved in the embolism and shock that result when heartworms die.  Doxycycline treatment is typically prescribed for four weeks prior to Immiticide® treatment and is relatively inexpensive and considered safe.   Be sure to discuss this treatment addition with your veterinarian!

There are severe complications that can occur following Immiticide® treatment that need to be monitored for.  Typically the attending veterinarian will keep the dog they are treating for several days during and after treatment to ensure the best outcomes are possible.  The most serious complication is the development of severe pulmonary thromboembolism.  This is caused by presence of dead heartworm fragments and lesions caused by the living heartworms and inflammation in the arteries and capillaries of the lungs.  Some degree of pulmonary thromboembolism will occur following the treatment process, it is important to keep the dog very quiet to minimize these embolisms and the effects of them.  Clinical signs associated with treatment include fever, cough, and sudden death.