Coverage has greatly increased since WHO's Expanded Program on Immunization began in 1974, and the results are encouraging (Table 1). In 2009, global DTP3 (three doses of the diphtheria-tetanus-pertussis combination vaccine) coverage was 82% — up from 20% in 1980. However, millions of children worldwide were not reached by DTP3 in 2009, including many in South Asia and sub-Saharan Africa.