We place great importance on the health of our dogs, making every effort to ensure the new addition to your family arrives healthy.
We have learned that there is a period of time in the developmental stages of a heartworm where the juvenile heartworm cannot be killed by the use of preventatives, nor are they detected by any standard heartworm test. As a result, dogs over 6 months of age could possibly be infected with heartworm unknown to us. Currently there is nothing offered by modern science to avoid this scenario.
It is recommended by the American Heartworm Society that after the initial negative test, the dog be placed on monthly preventatives and retested again 6 months from the test date to ensure the original test was not done in this stage of development.
If you are adopting a puppy under the age of 6 months, it is important that you continue giving monthly preventatives and have your dog tested annually.
HHDR does stand by the health of our dogs and in the event the second test is positive, we will reimburse the adopter up to $600 at the vet of their choice after treatment is completed. It is necessary that the following conditions be met:
The newly adopted dog is placed on monthly heartworm preventative prescribed by your veterinarian and there is proof provided by payment receipt or confirming with your vet preventatives were purchased.
The second test is done within 6 months from the original test and results are documented and submitted to HHDR.
If these conditions are not met, we reserve the right to refuse financial assistance in the treatment of the Heartworm disease.
Please have your dog retested six months after the last test date on your dog’s medical records.
Heartworm Transmission
AKA “why we need to test dogs every 6 months when they first start preventions”
Life cycle:
Heartworm is transmitted from an infected dog to another dog via a mosquito.
Heartworm circulating in the original infected dog is juvenile, or larva. The larva is ingested by the mosquito and develops in the mosquito for 10-14 days (Stage L1—L3) before the mosquito can pass it to a dog.
The L3 and L4 stages develop in the muscles and tissues of the newly—infected dog over 6—8 weeks (45-65 days), then move into the bloodstream as a developing adult (L5) for 4-5 months before maturing to a true adult that then begins to pass larva into the bloodstream over the next 5-7 years.
Preventions: Heartworm preventions act by killing the larval or juvenile stages of heartworm, but they are ONLY effective on L1-early L4. Later stage L4 and L5 and adult heartworm are not affected by monthly preventions.
The heartworm testing done by Accuplex or 4Dx or other similar “SNAP" tests looks for a protein produced by the adult heartworm, which is only produced 7 months after heartworm is transmitted to the dog. Therefore, there is a gap of 4-5 months where heartworm preventions are not effective at killing the older larvae and adults and while the test cannot identify a positive heartworm infection.
Recommendations:
The American Heartworm Society recommends testing all dogs 7 months or older prior to beginning heartworm prevention, then retesting those dogs 6 months later to identify any dogs that were carrying L4. L5, or early adults in the bloodstream when the first test was done (and again 6 months after that, then every 12 months). This allows earlier identification of positive dogs and treatment can be started before much damage can progress.
