Shouldn't this be more of a temporary problem? As soon as there is a vaccine its patents will expire at least 20 years afterwards. And then lots of much cheaper vaccines will flood the market.
India would probably just violate the patent, claiming national security reasons, and sell it for ~production cost throughout the world. The USA might enforce a patent domestically, and it would be a rational economic choice for insurers to pay for it for many patients instead of long-term treatment if someone contracts AIDS otherwise -- if you have a 0.1% risk of contracting AIDS in a lifetime, and lifetime treatment costs $1mm, it's worthwhile to pay $100-$1000 for it.
A charity (or government) might pay for full rights to the vaccine globally, and then distribute it for the good of humanity (and to burnish their reputation), but the really out of the box thing would be for a consumer product company to distribute the vaccine cheaply, purely as a form of PR. Imagine: "Coca-Cola, the drink that is good for you. Remember, we cured AIDS."
I think his point is that much of the problem of preventing the spread of HIV has less to do with the science of killing the virus, and more to do with the difficulty of actually getting it in the hands of people who need it. There are already very cheap, readily-available ways of preventing HIV transmission (condom use comes to mind), but people aren't using those. The reasons are varied, but some cite misinformation, cultural misconceptions, government ineptitude, and so on. Even if there were a 99% effective HIV vaccine that were as cheap as water, it still wouldn't make it into the hands of every person in the developing world. Proof of that is the fact that we can't even get water to all of these people.
Not sure how good an analogy this is. I suspect it would be moderately expensive (i.e. on the order of a few billion dollars), but possible to deliver a liter of clean water to nearly everyone in the developing world. The problem is, that solves their water problem for about 12 hours, if you're being generous. Solving their problem long term is the hard part. With vaccines, you only need to visit the people a finite number of times, and then you're done. Given that HIV is sexually transmitted (and assuming that the vaccine can be given relatively young), you wouldn't even need especially frequent visits to immunize the next generation of people.
Here's a relevant TED Talk about pandemics: http://www.ted.com/talks/larry_brilliant_wants_to_stop_pande...
"Herd immunity" protects the others -- basically, the disease itself can't spread if a sufficient number of people are vaccinated, so it dies out in a few generations (of the disease, not of humans).
The problem is the standard models of herd immunity depend on some simplifying assumptions which may be true in livestock, but are not true in humans -- specifically, that it's a homogenous population with equal chance of giving any other individual the disease, and that vaccines will be distributed fairly randomly as well.
If you have backwater villages which never get vaccinated, and are highly interconnected, you can end up with persistent reservoirs of disease, even if it's only 1% of your overall population. Then, you can have periodic epidemics when an individual from that area travels to an unvaccinated area elsewhere (because compliance rates on vaccination go down once the disease is "cured" in a population).
(I know about this from drinking with some of the UN/WHO vaccination people in Afghanistan)
I think things should work out well in the end, but it might take a while.
There are places where the official government-endorsed treatment for HIV was sex with a virgin. There are religious notions that declare use of birth control sinful. There are moral police that call education about safe sex (instead of abstinence) wrong, despite its proven efficacy.