Three additional horses have been confirmed positive with West Nile virus (WNV) in Nevada in the past three weeks according to information from the Nevada Department of Agriculture (NDA). None of the horses had been vaccinated.
“Vaccination is the best protection horse owners have for their animals,” said Dr. J.J. Goicoechea, the NDA’s state veterinarian. “With the increased numbers of mosquitoes this year, it’s important all horse owners take this precaution to prevent the spread of disease.”
The NDA stated that arboviral diseases such as WNV are transmitted to humans primarily through the bites of infected mosquitoes, ticks, sand flies or midges. Every year, the NDA closely monitors several arboviral diseases to protect public health and safety and the agriculture industry. In addition to WNV, the Animal Disease Laboratory at the NDA tests for two other prevalent arboviral diseases: Saint Louis Encephalitis virus (SLE) and Western equine encephalitis virus (WEE). Although these diseases cannot be transmitted from a horse, all three can cause severe illness and death both in horses and humans.
“Vaccinations, in conjunction with practices that reduce exposure to mosquitos, are very effective in protecting horses from WNV,” Goicoechea said. “It’s not too late to prevent the spread of disease.”
WNV has been prevalent in Nevada since 2004 while SLE and WEE have been widespread in the western United States for decades. Since the Aedes aegypti mosquito has been found in southern Nevada this year, the laboratory also monitors and tests for Zika virus.
The NDA stated that all Nevada residents should take precautions such as eliminating mosquito breeding sites around houses and barns, using insect repellents to fight the bite and keeping horses vaccinated against WNV, SLE and WEE.
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