Published on Wednesday, 30 November -0001 00:00
The Minnesota "state bird" is responsible for keeping me busy, starting every spring ... not just itching, slapping, swatting, and spraying myself, but also testing dogs, and vaccinating horses against the diseases mosquitoes transmit.
The diseases I'm referring to are heartworm disease in dogs and cats, and Eastern/Western Encephalomyelitis and West Nile Virus in horses. Of all the things we can do for our dogs, heartworm prevention has to be considered mandatory. Prevention consists of an annual blood test due to the silent nature of the disease, and administration of monthly medication to kill off the "microfilaria" deposited by the mosquitoes. Failure to do either of these two simple dog-owner responsibilities puts your dog in jeopardy of contracting and harboring a preventable, fatal disease. Failure to do these for your dog puts everyone else's dogs at risk as well, because mosquitoes pick heartworm up from your dog and put it in your neighbor's dog. Indoor mosquitoes are more common than indoor dogs and cats, so even if paper-trained Fluffy or litterbox-trained Boots wouldn't dream of leaving their air-conditioned comfort, the mosquitoes don't discriminate. We see heartworm disease in our area multiple times every year, it is fatal if left untreated, can be fatal even with treatment, and financially, it is much more expensive to treat than prevent. Our recommendation is to give preventative medication every month, year-round, for minimal risk even if an occasional dose is forgotten, spit out, vomited up, or even if there was a late season indoor mosquito still hanging out looking for one last helping of your dog. Annual testing in the spring picks up the previous year's exposure, so infection can be detected as early as possible. Cats are less susceptible to heartworm, but treatment of feline heartworm disease is highly unsuccessful and therefore highly fatal. The best heartworm preventative for cats is actually a monthly topical product, and it also treats them for two common intestinal parasites, ear mites, and fleas. Go to for the best information about the disease.
Horses are not going to get heartworm disease, but they will get a few mosquito diseases that our dogs and cats will not: Eastern Encephalomyelitis, Western Encephalomyelitis, and West Nile Virus. All of these could cause fairly vague symptoms such as fever, stiffness, and poor appetite, but they could also cause incoordination and abnormal mental status or behavior. Rabies, although not a mosquito-borne disease, can cause some of these same symptoms, so not coincidentally, vaccination against all of these diseases, (EEE, WEE, WNV, rabies) in addition to tetanus, is considered "core," meaning every horse, everywhere, every year. Visit www.aaep.org for the best horse vaccination recommendations.
Please do your animals and everyone else's animals a service by helping to control these mosquito-borne diseases through testing and preventing in the case of heartworm disease, and vaccinating in the case of the horse diseases.
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