Diversification of vaccine manufacture
Over the past decade, there has been substantial diversification in the manufacture of vaccines, including the growing importance of prequalified vaccines produced by manufacturers in low- or middle-income countries. In addition to producing vaccines for their own countries, these manufacturers can often provide large volumes at low prices on the international market and now represent an increasing proportion of the vaccines procured by UNICEF and the Pan-American Health Organization (PAHO) Revolving Fund for Vaccine Procurement. At the end of 2008, there were 83 different vaccine products prequalified by WHO, of which 37 were manufactured in low- or middle-income countries.