20. Vaccine–Preventable Diseases

Abstract

Because vaccination has had a significant effect on reducing mortality and morbidity from childhood diseases, it is one of the key strategies for achieving the child health Millennium Development Goals endorsed by the United Nations. The World Health Organization's Expanded Program on Immunization is one of the most cost–effective public health programs, focusing on tuberculosis, diphtheria, pertussis (whooping cough), tetanus, polio, measles, hepatitis B, and yellow fever. More recently, a consortium of major international development partners, private philanthropies, nongovernmental organizations, and the vaccine industry has helped increase access to new and underused vaccines in the world's poorest countries, improve access to basic immunization services, and accelerate research and development into new drugs and technologies.

The epidemiology and burden of vaccine–preventable diseases vary by country and region for numerous reasons, including differences in vaccine uptake, geography, seasonal patterns, nutritional status, and travel to and from other countries. The greatest burden of disease occurs in Sub–Saharan Africa, where immunization programs have been least successful. Governments in developing countries as well as their development partners are challenged to find ways to finance and sustain immunization programs, especially as they seek to achieve higher coverage levels and introduce new vaccines.

In the short term, policy makers can explore ways to improve the cost–effectiveness of vaccination over other interventions. For example, immunization program costs can be lowered by using the most efficient mix of delivery strategies, reducing vaccine waste, and reducing the number of doses required to achieve immunity. Targeted approaches also could yield high returns, especially in those regions with poor control of vaccine–preventable diseases. In some countries, however, the challenge will be to sustain high immunization coverage in the face of community perception that vaccine–preventable diseases no longer constitute a major public health threat.