Despite worldwide attention to the dangers of mosquitoes and the consequences of diseases they transmit to humans, there is little awareness that the same mosquitoes are the vectors that transmit heartworms to dogs.

For decades, canine heartworm prevention protocols have not changed, so it’s now time to fight against both parasites involved in the heartworm lifecycle—and that means fighting the vector and the heartworm. 

If you are prescribing macrocyclic lactones, you’re only fighting half the battle against heartworms. The Double Defense Heartworm Protocol is an approach that protects dogs from mosquitoes, which may transmit heartworms as well as from the infective larvae on the inside. This new standard of care means that every dog should be on a macrocyclic lactone year-round and a mosquito repellent to double the protection against heartworm transmission.


Studies prove Double Defense protects dogs better than using a heartworm preventive alone1 and when using Double Defense, there were:

  •       Fewer mosquito bites1
  •       Fewer infected mosquitoes1
  •       Fewer infected dogs1
  •       Fewer L3 transmitted2
  •       No adult heartworms in dogs2


The studies prove Double Defense prevents mosquitoes from feeding on dogs and in turn, spreading heartworm microfilariae and larvae, is an effective approach to stopping the spread of heartworms from dogs to mosquitoes. This approach targets not only heartworm disease, but also the vector. Effective use of mosquito repellents is a basic tool in the fight against malaria, West Nile virus and Zika and now studies prove it’s time to bring the same approach to preventing canine heartworm transmission.

Visit to learn more about Double Defense and to hear from industry leaders who have weighed in on the studies.


1.McCall, J.W., Hodgkins, E., Varloud, M., Mansour, A., DiCosty, U. (2015, July). Inhibition of the transmission of Dirofilaria immitis to mosquitoes by weekly exposure to microfilaremic dogs treated topically with dinotefuran–permethrin-pyriproxyfen. Abstract presented at the meeting of the American Association of Veterinary Parasitologists, Boston, MA.

2.McCall, J.W., Hodgkins, E., Varloud, M., Mansour, A., DiCosty, U., McCall, S., Carmichael, J., Carson, B., Carter, J. (2016, August). Blocking of the transmission of Dirofilaria immitis L3 (JYD-34 ML resistant strain) from infected mosquitoes to dogs and prevention of infection in dogs treated topically with dinotefuran-permethrin-pyriproxyfen and orally with milbemycin oxime alone or in combination. Abstract presented at the meeting of the American Association of Veterinary Parasitologists, San Antonio, TX.

Sponsored content was provided by Ceva Animal Health.

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