Mumbai: Thirty years since the first reported case of a person infected with the Human Immuno-deficiency Virus or HIV and 25 million deaths later, there's still no realistic prospect of a vaccine against the disease, AIDS.
One of the main reasons is that HIV is such a complex virus. There are two strains - both with three subtypes each. Different continents see different sub-types. So far, scientists have identified 10 different patterns of the virus, but there could be many more and the virus also constantly evolves.
More than $100 million have been pumped into research, and there have been at least 80 clinical trials, including the massive trial in Bangkok in 2011, but we're still years away from a viable vaccine. Executive Director of the International AIDS Society Bertrand Audoin said, "It's just a matter of time. The last couple of years have seen major progress in research. We don't have anything in hand but we are closer to understanding the virus than ever before."
Clinical trials present difficulties. There are ethical concerns when people are involved, given the nature of the infection. And with animal trials, specifically those done on Macau monkeys the strain of the disease is similar, but not identical. About 22 vaccine candidates are being tested worldwide - the good news is, all that research has resulted in more effective treatment.
With no vaccine on the horizon, prevention is key and while UNAIDS estimates that India has seen a 56 per cent drop in new infections in 2012, it's too soon for complacency. Last year 25 million children worldwide were orphaned by AIDS.