Status of arenavirus vaccines and their application.

A limited but definite need exists for vaccines against Lassa, Junin, and Machupo viruses. Medical and laboratory personnel, as well as defined high-risk population groups, require protection from these highly virulent agents. To date little work has been done on inactivated vaccines for these viruses. A live attenuated Junin vaccine has been tested successfully in more than 600 persons, and a high-passage Machupo virus strain has protected rhesus monkeys against lethal infection produced by a homologous field strain.Work has been initiated on possible heterologous protection induced by infection or antigenic stimulation with arenaviruses not pathogenic for man. Crucial for the eventual development of effective vaccines are the construction of more maximum security laboratories and the further elucidation of the experimental and natural biology of the agents in lower animals and man.