Beaufort County, South Carolina – First Death from Eastern Equine Encephalitis in Over 20 Years

The South Carolina Department of Public Health (DPH) has reported the first confirmed death from the eastern equine encephalitis (EEE) virus in Beaufort County, marking a grim milestone as it is the first human case since 2020 and the first death attributed to EEE in the state since 2003.

EEE is transmitted to humans through infected mosquito bites, and importantly, it is not spread from person to person. While many individuals may experience mild febrile illnesses, severe symptoms can lead to neurological complications such as encephalitis and meningitis. Approximately 30% of those who develop severe cases of EEE die from the infection, and survivors often face long-term neurological challenges. There are currently no vaccines or specific treatments available for EEE in humans, underscoring the critical nature of preventive measures.

In light of this recent tragedy, Dr. Edward Simmer, the interim DPH director, emphasized the rarity but severe implications of EEE cases, indicating that the situation requires immediate community action to prevent further infections.

Prevention Measures and Response

To mitigate the risk of mosquito bites, the DPH recommends several preventative strategies. These include wearing long sleeves and long pants, using EPA-registered repellents such as DEET, and eliminating standing water around residential areas to reduce mosquito breeding. In response to the recent death, Beaufort County Mosquito Control has initiated multiple truck spraying applications in the area surrounding the reported case. Additionally, plans are underway for a helicopter spray operation to provide more extensive coverage.

As part of the monitoring efforts, mosquito traps are being set up for EEE virus testing in the area. So far in 2025, no EEE-positive mosquitoes have been detected near the location of the reported human case. The closest routine surveillance trap was situated approximately 2.5 miles away from the infection site. Furthermore, during the period between mid-July and August, ten horses across various counties in South Carolina tested positive for the EEE virus. Counties reporting EEE-positive horses include Aiken, Colleton, Horry, Jasper, Orangeburg, and Sumter.

Public Health Initiatives

The DPH works in collaboration with the Centers for Disease Control and Prevention (CDC) to monitor and respond to mosquito-borne diseases effectively. This includes conducting surveillance through mosquito trapping and testing, as well as coordination with the Clemson University Veterinary Diagnostic Center to test animals such as horses. The DPH advises the public on mosquito prevention strategies through the “7 Ts” guideline, which aims to educate residents on steps they can take to reduce mosquito populations and limit exposure.

Context on Eastern Equine Encephalitis

EEE is a rare but potentially lethal virus that can lead to severe neurological damage. Affecting both humans and horses, the significance of monitoring and controlling mosquito populations is vital to preventing outbreaks. The history of EEE in South Carolina underscores the need for vigilance, given the occurrence of sporadic cases over the years, particularly among equine populations.

Frequently Asked Questions

Key Features of Eastern Equine Encephalitis Reporting