Evaluation in Rhesus Monkeys of a Bivalent Live Attenuated Dengue Vaccine Containing Types 2 and 4 Viruses

摘要

The purpose of this study was to determine whether a bivalent (dengue-2-4) vaccine could confer immunity in rhesus monkeys against wild type virus infection. It was found that: (1) DEN-2/S-1 animals showed an anamnestic response as well as undetectable viremia after challenge with w.t. DEN-2 virus. Divalent vaccines also showed an anamnestic response after DEN-2 virus challenge. (2) DEN-4 vaccine did not elicit a measurable immune response in 6/8 animals as judged by PRNT, augmented N tests and by DEN-2 challenge experiments. An anamnestic response was observed in 2/8 animals. (3) N antibody levels of most of the vaccinated animals declined markedly on or before post vaccination day 150. (4) Viral interference among the two different vaccine serotypes could not be demonstrated.