Approach Considerations
No specific treatment other than supportive care is available. Venezuelan equine encephalitis virus is an RNA virus; therefore, antivirals that have been successful against deoxyribonucleic acid (DNA) viruses are ineffective. Treatment of Venezuelan equine encephalitis is symptomatic and in the ED most likely involves correcting fluid deficiencies.
Patients with neurologic manifestations of Venezuelan equine encephalitis should be transferred to a facility that can provide intensive care treatment, if necessary.
Supportive care in nonneurologic Venezuelan equine encephalitis
Patients with nonneurologic Venezuelan equine encephalitis virus infection generally require only supportive care, including fluid management for dehydration and electrolyte derangement caused by fever and vomiting.
Supportive care in Venezuelan equine encephalitis with neurologic manifestations
Patients with neurologic manifestations of Venezuelan equine encephalitis require prompt supportive care to reduce the risk of mortality.
Appropriate measures include standard anticonvulsant therapy as treatment for seizures; fluid management for dehydration and electrolyte imbalance produced by fever, vomiting, decreased oral intake, and inappropriate ADH secretion; and proper airway and respiratory management in those progressing to coma.
Neurosurgical evaluation and monitoring for increased intracranial pressure are beneficial. Prevention and treatment of secondary bacterial infection significantly improve the patient's prognosis.
Consultations
Contact an infectious disease specialist if Venezuelan equine encephalitis is suspected. In addition, involve the county and/or state health department. Neurosurgical evaluation and monitoring for increased intracranial pressure, when possible, is beneficial.
Vaccine Development
Animal models used in vaccine development include hamsters, rabbits, mice, and guinea pigs. A vaccine has been developed for horses. [14, 15] Cross reactivity and protection in horses has also been described with related alpha viruses including Eastern Equine Encephalitis, and Western Equine Encephilitis.
Human trials are currently underway to develop a vaccine for Venezuelan equine encephalitis. A phase 2 clinical trial sponsored by the US Army Research and Development Command is expected to be completed in 2023 using C-84 is a formalin-inactivated vaccine. Live attenuated vaccines, V3526, and TC-83 are also under investigation. Studies have shown that the V3526 vaccine has been safe and efficacious in the treatment of horses. Vaccination with V3526 results in a lack of detectable viremia; however, further research is needed to determine whether this vaccine will safely confer immunity in humans. [16, 17, 18]
Deterrence and Prevention
Protection from mosquito bites in endemic areas is important. Visitors to endemic areas should take appropriate precautions to avoid mosquito bites, including proper clothing, insect repellant, and mosquito nets. Large-scale aerial insecticide applications may decrease the number of disease-carrying mosquitoes.
