Dr. Robert Cross, one of the lead researchers on the study, said the single injection vaccine elicited protection against observable disease in 100 percent of subjects when administered seven days prior to exposure and prevented serious disease with full recovery in 100 percent of subjects vaccinated three days prior to exposure.
"While Lassa is endemic in West Africa, imported cases have occurred in both Europe and the United States as a result of commercial air travel. Besides Dengue, Lassa Fever is the viral hemorrhagicthat is most often exported by travel to other parts of the world. This is possibly due to a long incubation period," said Dr. Courtney Woolsey, co-lead author of the study.
Lassa virus is an acute viral infection that originates and spreads through contact with a common African rat. Symptoms typically appear one to three weeks after exposure. While the majority of infections are mild or even asymptomatic, in 20 percent of cases the disease can progress to more serious symptoms including hemorrhaging, severe respiratory distress, repeated vomiting, facial swelling, pain in the chest, back, and abdomen, and shock.