West Nile virus is a disease transmitted to humans by the bite of an infected mosquito. The mosquito initially acquires the virus from biting birds that carry it. Relevant studies suggest as many as 80% of people with West Nile do not develop symptoms and never realize that they had an infection. Symptoms that do appear generally go away on their own, but more severe issues can develop and require immediate medical attention.


1. Flu-Like Symptoms

When people exhibit symptoms of West Nile, they may mistake them for the flu. Some individuals develop a fever without a clear cause, called a febrile illness; this affects around 20% of people with the virus. Nausea frequently occurs alongside the fever. The fever is usually low-grade, although it can be higher in severe cases. Symptoms of fatigue, generalized aches, and loss of appetite may also be present.

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