Abstract

Rift Valley fever virus, a pathogen to ruminants, camelids, and humans, is an emerging mosquito-borne bunyavirus currently endemic to Africa and the Arabian Peninsula. Although animals are primarily infected via mosquito bites, humans mainly become infected following contact with infected tissues or fluids of infected animals. There is an urgent need for adequate countermeasures, especially for humans, because effective therapeutics or vaccines are not yet available. Here we assessed the safety, tolerability, and immunogenicity of a next-generation, four-segmented, live-attenuated vaccine candidate, referred to as hRVFV-4s, in humans.