Arboviral diseases, Eastern equine encephalitis virus disease in Maryland

• Mild/Systemic Disease (less common): Fever, chills, malaise, joint pain, muscle aches, lasting 1-2 weeks.
• Severe/Encephalitic Disease (more common in human cases):
• Sudden onset of headache, high fever, chills, vomiting.
• Disorientation, seizures, drowsiness, coma.
• Permanent neurological damage is common in survivors.

EEE virus is primarily transmitted to humans and horses through the bite of infected mosquitoes. The virus circulates naturally between birds and mosquitoes, mainly *Culiseta melanura*. So-called 'bridge vectors,' such as *Coquillettidia perturbans* and *Aedes sollicitans*, then transmit the virus from infected birds to humans and horses, who are considered 'dead-end hosts' as they do not develop sufficient viremia to infect other mosquitoes.

• Use EPA-registered insect repellents (e.g., DEET, picaridin) when outdoors.
• Wear long sleeves and pants during dawn and dusk, when mosquitoes are most active.
• Eliminate standing water around your home to reduce mosquito breeding sites (e.g., empty tires, buckets, flowerpots).
• Ensure windows and doors have intact screens to keep mosquitoes out.
• There is no human vaccine available for EEE virus; a vaccine is available for horses.