Safety and immunogenicity of an inactivated eastern equine encephalitis virus vaccine.

Background: Eastern equine encephalitis virus (EEEV) is a mosquito borne alphavirus spread primarily in Atlantic and Gulf Coast regions of the United States. EEEV is the causative agent of a devastating meningoencephalitis syndrome, with approximately 30% mortality and significant morbidity. There is no licensed human vaccine against EEEV.

Phase 3 Efficacy Trial of Modified Vaccinia Ankara as a Vaccine against Smallpox.

Background: Many countries have stockpiled vaccines because of concerns about the reemergence of smallpox. Traditional smallpox vaccines are based on replicating vaccinia viruses; these vaccines have considerable side effects.

Methods: To evaluate the efficacy of modified vaccinia Ankara (MVA) as a potential smallpox vaccine, we randomly assigned 440 participants to receive two doses of MVA followed by one dose of the established replicating-vaccinia vaccine ACAM2000 (the MVA group) or to receive one dose of ACAM2000 (the ACAM2000-only group).