Sadly, many people in these nations don't have access to proper health care and most can't afford the price of retroviral drugs, which sometimes represents more than their whole yearly salary alone.
One promising development in the global battle against the spread of HIV is the recent efforts at allowing certain nations the right to produce generic versions of badly-needed medicine during an epidemic. Although this circumvents the "patent" laws of the Western world, at least it offers some hope to the people being stricken by this sinister disease.
Some would argue that by encouraging generic drug manufacturers to prosper, patients won't see the real benefit because there is nothing stopping these companies from jacking up their prices. This is a tough question because you hear two different stories every time it comes up. Who to believe? The NGO's or Medecins sans Frontieres? What about Bristol-Myers Squibb, who just announced $30 Million USD of aid for HIV sufferers from several African nations? (Is it possible that the Western drug companies have a heart? Possibly.) This is something that we should keep an eye on.
Even if you don't live in Sub-saharan Africa, with all the various S.T.D.'s prevalent in Western nations, using a condom is your best option, at least until you and your partner are absolutely certain that you're not at risk (ie. getting tested repeatedly, etc.)
Condoms don't only stop most STD's from spreading--they also prevent unwanted pregnancy. Today, as I was picking up some items at the drug store in my community, I walked by a worried young gentleman speaking hurried Arabic on his cellphone. A sales lady was giving him advice about which pregnancy kit to choose and he was translating this to his girlfriend over the phone. I didn't say a word to him (he needs his privacy at such a stressful moment) but I stopped in the condom aisle on the way out and picked up a box of Trojans. Better safe than sorry!