Middle East respiratory syndrome: current status and future prospects for vaccine development.

The outbreaks of Middle East respiratory syndrome (MERS) previously in Middle East and recently in South Korea have raised serious concerns worldwide, reinforcing the importance of developing effective and safe vaccines against MERS-coronavirus (MERS-CoV). A number of vaccine candidates have been developed on the basis of viral vectors, recombinant proteins, DNAs, nanoparticles, and recombinant MERS-CoV, and some of them have shown efficacy in laboratory animals. However, the paucity of financial support has made it difficult to transfer effective candidates from the preclinical stage to clinical trials. Here, we summarize currently available MERS vaccine candidates and illustrate strategies for future development, with the aim of provoking government agencies and Big Pharma to invest more funds for developing efficacious and safe MERS vaccines.