Eastern Equine Encephalitis
Eastern Equine Encephalitis (EEE) is a viral infection, transmitted to humans via the bite of an infected mosquito. It is most commonly found in eastern, Gulf and north central USA and adjacent Canada, in parts of central and South America and the Caribbean. It is particularly found in swampy areas during the summer and early autumn months, when there is high mosquito activity. Salt marsh mosquitoes are one of the main culprits, thus EEE is often a coastal phenomenon due to the large numbers of these mosquitoes along the shore line. In the USA most cases are reported from the states of Florida, Georgia, Massachusetts, and New Jersey (see further resources)
The virus can cause disease in humans, horses and birds. Human cases of EEE are thankfully very rare (on average 5 cases each year in the USA), but because of its high death rate it is considered one of the most serious mosquito borne diseases in the United States.
Incubation of the disease is usually between 3-10 days, with high fever followed by all the features of meningitis, including coma and convulsions. Of those individuals who contract the disease approximately 35% may die and those that survive the initial illness may suffer long-term neurological damage.
There is no specific treatment for EEE. Patients will often require hospitalisation and intensive care support to assist with breathing and circulatory problems.
Recommendations for Travellers
Travellers at highest risk are visitors to endemic areas particularly if they will be engaging in outdoor work or recreational activity. Those aged over 50 years and younger than 15 years seem to be at higher risk of developing severe illness if infected with the virus. No human vaccine against EEE virus is currently licensed. Prevention is focused on mosquito bite avoidance including personal protective measures (e.g. use of insect repellent, cover-up clothing) and environmental measures (e.g. use of nets, spraying breeding sites)
Centers for Disease Control and Prevention