Which mosquito-borne virus is considered the deadliest in the United States?

The Eastern Equine Encephalitis (EEE) virus is recognized as the deadliest mosquito-borne virus in the United States due to its high mortality rate. Though it is relatively rare, when EEE does occur, it can lead to severe neurological disease, with a mortality rate of about 30% among those infected.

Additionally, survivors often experience long-term health effects, making it particularly concerning. The virus is typically transmitted to humans through the bite of infected mosquitoes, with specific species such as Culiseta melanura playing a key role in its transmission cycle. Public health surveillance in areas where EEE is present is critical for monitoring mosquito populations and advising communities, especially when the risk of outbreaks increases during peak mosquito season.

In contrast, while the West Nile Virus is widespread and has caused significant illness, it generally carries a lower mortality rate compared to EEE. La Crosse Encephalitis is more common but substantially less deadly. Chikungunya, although causing debilitating symptoms, has not been associated with high mortality rates in the U.S. population. Thus, EEE stands out as the most lethal mosquito-borne illness in terms of fatality.