Recent advances in the development of Lassa fever vaccines

Lassa fever is an acute viral disease caused by Lassa virus(LASV). The virus is mainly transmitted to humans by a rodent reservoir, Mastomys natalensis. The infection is endemic in West African countries, resulting in hundreds of thousands of cases annually, and causing approximately thousands of deaths each year. Due to its high pathogenicity, LASV is recognized as a potential agent of bio-warfare. Currently, there are no licensed vaccines for Lassa fever. Studies have shown that the vaccine prepared by in-activated LASV is not ideal for eliciting a protective immune response. Recently, several promising vaccine candidates against Lassa fever have been developed, such as replication-competent virus-vectored vaccines, replication-deficient virus-vectored vaccines and DNA vaccines. However, these novel types of vaccine candidates against Lassa fever remain to be pre-clinically and/or clinically evaluated.