HIV/AIDS is a giant problem. North of 35MM people are living with HIV worldwide and more are infected every day. Yes we have made strides in reducing infection rates, but we are far from solving this problem with existing approaches. To put this in context, nearly 5,000 people a day die from AIDS. That is like 10 747s falling out of the sky every single day. The only solution is a vaccine which is why we are doing what we are doing. There are many big problems for us to solve on our planet. HIV/AIDS is one of the biggest and hardest to solve.