Vaccine clears HIV virus in monkeys, according to a new study that showed an HIV-like virus was eliminated from these primates.

Researchers published their findings in Journal Nature, which showed that vaccinated monkeys can clear Simian Immunodeficiency Virus (SIV) infection from their bodies. SIV is an HIV-like virus.

This could be a possible huge step in the future of clearing a virus like HIV that has killed millions around the world. These monkeys could become very vital in saving lives. The SIV virus that was used is actually 100 more times deadly than HIV, according to BBC.

Prof Louis Picker, from the Vaccine and Gene Therapy Institute at Oregon Health and Science University, said in the journal: "It's always tough to claim eradication - there could always be a cell which we didn't analyze that has the virus in it. But for the most part, with very stringent criteria... there was no virus left in the body of these monkeys."

Monkeys infected with the disease are supposed to die within two years, though half of them didn't even have the virus at all after being injected with the vaccine is based on another virus called cytomegalovirus (CMV), which belongs to the herpes family.

Instead of causing disease, it has been modified to spur the immune system into action to fight off the SIV molecules.

"It maintains an armed force, that patrols all the tissues of the body, all the time, indefinitely," explained Prof Picker.

Prof Picker also said his team was still trying to work out why the vaccination worked in only about half of the monkeys because the virus was cleared in 9 out of the 16.

"It could be the fact that SIV is so pathogenic that this is the best you are ever going to get," he said. "There is a battle going on and half the time the vaccine wins and half the time it doesn't."