In January, GlaxoSmithKline (GSK) launched Rotarix, a rotavirus vaccine, in Mexico. That launch may alter the course of vaccine development for the better: Rotarix was the first vaccine from a major pharmaceutical firm to debut not in the United States or Europe but in a poor country. The story of Rotarix (see "The Vaccine That Almost Wasn't") shows that getting vaccines where they are needed most requires giving companies like GSK financial incentives. The emergence of what can be thought of as a superbuyer for vaccines -- the Global Alliance for Vaccines and Immunization (GAVI) -- may help create those incentives.

Before GSK's Rotarix, the vaccine story usually went like this: A drug company would develop a vaccine for a European country or the United States. It would charge a relatively high price for about 15 years, then, once it had made a profit, and the medicine had gone off patent, it would introduce the vaccine at a lower price to poor countries. The trouble with this model is not just that 15 years is a long time to wait; it's also that certain diseases are much more dangerous in poor countries than in rich ones.