Eastern Equine Encephalitis (EEE) and West Nile Virus (WNV) in Dogs and Cats

     Technically canines and felines can get both of these viruses, but it is extremely rare. There is minimal research on EEE in canines, and even less on felines, because the disease in these pets is so uncommon. EEE most commonly affects equines. Very few cases of EEE in dogs have been reported since the disease was first documented in Massachusetts in 1836. Similarly, WNV is rarely reported in canines and felines. A study in New York, in 1999, showed that about 7% of a tested canine population had positive antibodies for WNV, but never displayed symptoms. The study also checked felines but did not find any of them to have the antibodies for WNV. EEE and WNV occur among birds and are transmitted from bird to bird by mosquitos. In years when the environmental conditions are right for elevated mosquito populations, there are more documented cases of both EEE and WNV in horses and humans. Signs of EEE and WNV in horses (and rarely canines or felines) are often neurological, including fever and ataxia. In people flu-like symptoms, a stiff neck, and headaches are signs of the diseases.

     The bottom line is that while both of these mosquito borne diseases are rare in dogs and cats, we recommend owners take the same precautions for their pets as they do for themselves. Eliminate walks or play times outside after dusk, wear repellents if necessary, and of course remove all standing water sources from outside your home as this is prime source for mosquito breeding. If you have any further questions or concerns, please feel free to call our office.

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