Mosquito-Borne Diseases
As you may already know, there are a number of diseases carried by mosquitoes which can affect both horses and humans. West Nile Virus and Japanese Encephalitis are both diseases which can cause neurological signs in horses.
In this article we explain the signs to look out for in your horse and ways you can reduce the likelihood of your horse becoming infected.
West Nile Virus
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What is West Nile Virus?
West Nile Virus (WNV) is a virus carried by mosquitoes which can affect both horses and humans, as well as other animals. However, the virus is ONLY transmitted through mosquitoes - therefore, horses and humans cannot give this virus to each other.
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What are the clinical signs of West Nile Virus?
While some horses infected with WNV do not show any signs of disease, others may be symptomatic. If the virus does enter the brain, it can cause inflammation and sometimes death. Clinical signs of WNV can include fever, incoordination, seizures, drooping lips, lip smacking, sensitivity to light, muscle fasciculations, grinding teeth, recumbency.
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How is West Nile Virus diagnosed?
WNV is diagnosed by a veterinarian through blood testing.
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How can you help to reduce the risk of West Nile Virus affecting your horse?
Good mosquito control is paramount in reducing the risk of your horse contracting WNV. Minimising access of horses to stagnant water, keeping water containers clean, frequent use of insect repellants, bringing horses indoors at peak mosquito feeding times (dawn and dusk), and keeping horses rugged when mosquitoes are present.
Additionally, managing your own contact with mosquitoes (clothing, repellents) can help to reduce your risk of developing this disease.
Japanese Encephalitis
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What is Japanese Encephalitis?
JE is, similarly to WNV, a virus which is spread by mosquitoes. Both horses and humans (as well as pigs) may become infected if bitten by an infected mosquito. However, an infected horse will not transmit this disease to a human.
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What are the clinical signs of Japanese Encephalitis?
Often, horses with JE will not show clinical signs of disease, so you may not know they are infected. Some horses may show signs such as a lethargy, loss of interest in eating, jaundice, incoordination, seizures, hyperexcitation, and a fever. In horses suffering severe neurological signs, this disease can be fatal.
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How is Japanese Encephalitis diagnosed?
JE is diagnosed by a veterinarian through blood testing.
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How can you help to reduce the risk of Japanese Encephalitis affecting your horse?
Reducing the risk of mosquitoes biting your horse is the best way to minimise the risk of disease due to Japanese Encephalitis. The use of hooded rugs, fly masks, and insect repellent may be beneficial. Additionally, the mosquito which transmits JE in Australia is most active at night for feeding outside, thus stabling horses between dusk and dawn if possible may also help.