Severe cases of equine encephalitis in humans begin with the sudden onset of headache, high fever, chills, and vomiting. The illness may then progress into disorientation, seizures, or coma. Eastern equine encephalitis (EEE) is one of the most severe mosquito-transmitted diseases in the United States with approximately 33 percent mortality. Most survivors experience significant brain damage. Mortality rates among horses with the eastern strain range from 70 to 90 percent. There is no specific treatment for EEE; care is based on symptoms. Equine encephalitis virus (EEV) can be aerosolized and cheaply produced thus representing a potential biological warfare threat.
Next-generation EEV vaccines, including live-attenuated, inactivated, attenuated Sindbis/Venezuelan EEV chimeric viruses, alphavirus replicons, and DNA vaccines, are all currently at various stages of development. But genetic vaccination with DNA plasmids expressing immunogenic proteins has numerous inherent advantages as a platform for the development of next-generation EEV vaccines. And Army researchers have developed nucleotides sequences which encode structural proteins of an EEV, codon optimized for expression in humans. These proteins can trigger either a total IgG antibody response or a neutralizing antibody response. These DNA plasmids may find application as a prophylactic or as a therapeutic.
- DNA vaccines can be rapidly and cost-effectively produced without propagation of pathogen
- Avoids problems of pre-existing or vector-induced immunity due to lack of a host immune response
- Exhibits a favorable safety profile
- US patent 9,555,090 available for license
- Non-human primate data available
- Potential for collaboration with Army researchers