In an experiment, 24 healthy rhesus macaques monkeys were given a vaccine containing a genetically modified form of the virus, rhesus cytomegalovirus (CMV).
Thirteen monkeys appeared to have been protected against simian immunodeficiency virus (SIV), the monkey equivalent of HIV. The vaccine also offered protection to 12 of the 13 macaques for another year.
The study says the vaccine works by stimulating the production of "effector memory T-cells", the type of blood cell which can remain vigilant in the body long after an infection has abated.
According to BBC News, other researchers welcomed the study, but said "safety issues would need to be addressed before similar approaches could be tried in humans."