Importance of Heartworm Testing*

*heartworm tests can only be done on K9's

Why is a Heartworm (HW) Test Important?

Having your pet tested prior to giving HW prevention is highly recommended due to the risks it can pose to a pet who may, unknowingly, already by infected. 

Heartworm preventative (such a Heartgard, Trifexis, Sentinel Plus) works by killing off any HW larvae that may have made its way into your pets body, via a mosquito bite, in the last 30 days (when given regularly and on schedule). However, when given to a pet who has never taken it before or has missed doses the concern lies in the possible presence of adult worms. Female, adult heartworms produce microfilariae (the stage before the larvae) in large numbers which then circulate in the bloodstream, ready to be consumed in a feeding by a mosquito to begin the cycle all over again. Monthly HW preventatives, though their main function is to kill larvae, also kill these stage 1 HW's which then can become blood clots that travel into the lungs and cause severe damage; this can cause an anaphylactic (allergic) reaction resulting in the need for hospitalization and/or death.

Heartworm has become an increasing concern in California which is why it is extremely important to test your pet annually, even when on HW preventative regularly, to be certain that the medication is working properly. It is also why it is equally important to have your pet on monthly heartworm prevention; HW can be a deadly and devastating parasitic infection that can be prevented with monthly treatments and annual tests.

Please consult with your veterinarian or veterinary staff if you are interested in HW prevention or having your pet tested. 

November 28, 2015


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