This chapter confirms that vaccination of children and women with the traditional EPI vaccines is a highly cost-effective public health intervention, although cost-effectiveness ratios vary by region, delivery strategy, and level of scale. Overall, vaccination has had a significant effect on reducing mortality and morbidity from childhood diseases and will be a priority intervention for achieving the child health Millennium Development Goals. Improving and sustaining measles control are among the most cost-effective interventions in high-mortality regions.
Establishing and maintaining high immunization coverage rates in many of the poorest developing countries have proven challenging for those with high population growth rates, limited infrastructure and resources, and fluctuating demand for services. According to historical coverage rate trends, Europe and Central Asia, Latin America and the Caribbean, and the Middle East and North Africa are expected to achieve 90 percent coverage of FIC by 2011, with East Asia and the Pacific, South Asia, and Sub-Saharan Africa lagging behind.
Increasing and sustaining higher immunization coverage rates will require further efforts so that disease control can be maintained, particularly when a perception exists at the community level that vaccine-preventable diseases are no longer a major public health issue. At higher coverage rates, further disease burden reductions will be smaller, which will affect relative cost-effectiveness. Targeted approaches in countries or at subnational levels could potentially yield high returns, especially in those areas with poor control of vaccine-preventable diseases.
Our analysis shows that the cost per FIC will increase as countries scale up immunization coverage and introduce new vaccines. Adding more antigens to traditional EPIs has been successfully accomplished in many countries, especially for Hib and hepatitis B vaccines. Although many of the new vaccines under consideration are more expensive than those for the original six targeted EPI diseases, they may still be relatively cost-effective compared with other interventions and with treatment costs. Our analysis shows a wide range of cost-effectiveness estimates depending on the type of vaccine, vaccine prices, coverage levels, and delivery strategy, with the additional incremental cost per person being relatively small for some new vaccines. Declines in unit prices of new vaccines also will affect cost-effectiveness results.
Financing and sustaining immunization programs are challenges that governments in developing countries and their development partners will face. The financial implications of reaching higher coverage levels and the simultaneous desire to introduce new vaccines will require policy makers to consider both the relative cost-effectiveness of interventions and the long-term budgetary implications.
Although global and regional estimates of cost-effectiveness of interventions are useful guides, further analytical work will be needed to evaluate the relative benefits (deaths and cases averted and DALYs) and costs (delivery and treatment) of vaccines for different delivery strategies and higher coverage rates, particularly at the country level.
1. For our analysis, the preimmunization era neonatal tetanus mortality rate per 1,000 live births is used: developed countries, 0.1; East Asia and the Pacific, 4.7; Europe and Central Asia, 0.4; Latin America and the Caribbean, 4.4; Middle East and North Africa, 4.7; South Asia, 15.3; and Sub-Saharan Africa, 10.2.
2. Because disease classification does not have a one-to-one correspondence with those prevented by vaccine, according to table 20.3 is based on estimates of the proportion of these illnesses that may be preventable by specific vaccines. For example, some meningitis and acute lower respiratory infections are caused by Hib or S. pneumoniae, and some cirrhosis is caused by hepatitis B.
3. A fully immunized child is a standard term that refers to a child who has received one dose of BCG vaccine, three doses each of oral polio vaccine and DTP vaccines, and one dose of measles vaccine. The number of FICs does not include children who have been partially immunized, so this measure underestimates the total effect on the disease burden. However, the number of FICs is representative of the effectiveness of the delivery system in providing access to immunization services to children. The authors are aware that fully vaccinating a child does not correspond to full immunity.
4. The mean population-weighted cost per FIC for the financial sustainability plans for immunization was US$21.06. The plans use DTP3 coverage as a proxy for FICs rather than coverage measured through population-based surveys (http://www.who.int/immunization_financing/en).
5. Assumptions about the relative distribution of FICs by strategy and region were based loosely on such factors as the proportion of the population with access to health services for fixed facilities and the likelihood of active mobile strategies.
6. A proxy for the total number of deaths averted is the sum of the individual deaths averted for each antigen in the traditional EPI. This figure may overestimate the actual number of deaths averted by fully immunizing children and therefore underestimate the cost per death averted. However, the values estimated by region appear to support previously reported estimates, and direct estimation of deaths averted was impossible given data and model limitations.