Scientists are close snd cautious over finding a safe and effective vaccine for HIV

As a result of previous failure, Scientists are now "cautiously optimistic" they're one step closer after a trial of a new vaccine has shown promising results in humans and monkeys.

According to a study published in The Lancet, the test treatment was found to produce an anti-HIV immune response in healthy adults, and protect monkeys against infection from a virus similar to HIV.

According to lead researcher Dan Barouch from Harvard Medical School, the study was an "important milestone" in HIV research, but that the results should be interpreted with caution.

"We're happy with the current results … but we can't assume that this vaccine will work in humans," Professor Barouch told The Health Report.

To test that theory in order to be sure maybe it will work in human, researchers will now take the vaccine to 2,600 women in southern Africa who are at risk of acquiring HIV.

"This is only the fifth HIV vaccine concept that will be tested for efficacy in humans in the 35-year history of the global epidemic," Professor Barouch said.

Almost 37 million people worldwide are living with HIV, with an estimated 1.8 million new cases every year.