Disease Eradication in the 21st Century: Implications for Global Health

3. Measles and Rubella Eradication in the Americas

3 Measles and Rubella Eradication in the Americas Seasoned Strategies for Sustained Success Jon Kim Andrus, Ciro A. de Quadros, Carlos Castillo-Solórzano, Mirta Roses Periago, and Donald A. Henderson Abstract This chapter reports on the measles and rubella eradication initiatives in the Americas, where initiatives demonstrate feasibility. Excellent, cost-effective interventions and the lack of an animal reservoir have made it possible to eradicate measles and rubella in the Americas. The driving force behind the eradication of measles, and more recently rubella and congenital rubella syndrome, has been to strengthen national capacity to conduct effective routine national immunization programs. High population immunity through vaccination coverage and high-quality surveillance are necessary, and the bene fits of vaccination for measles prevention and control are substantial. This chapter details the progress achieved and the implications for future benefits in both developed and developing countries. Introduction Among other factors, disease eradication is possible if there is no animal reservoir and excellent, cost-effective interventions like vaccination exist. Certainly, that is the case for both measles and rubella viruses (CDC 1999b). The bene fits of vaccination for measles prevention and control have been substantial, since measles traditionally has caused significant childhood mortality and disabilities . In the case of rubella, morbidity associated with congenital rubella syndrome has also been a huge burden on society, particularly in developing countries (Andrus et al. 2006). 26 J. K. Andrus et al. Four of the WHO regions (American, European, Western Pacific, and the Eastern Mediterranean regions) have regional measles eradication targets (WHO 2009), and the African region recently established an elimination goal for 2020. Measles eradication is feasible and practical (de Quadros et al. 2008). The challenge for regions embarking on measles eradication will be to maintain high population immunity with excellent vaccination coverage and highquality surveillance (Andrus et al. 2011a). As long as the virus is circulating anywhere in the world, meeting this challenge means confronting the possible importation of the measles virus. Some experts believe that a global measles eradication initiative could impede or prevent the eradication of polio. This opinion is contrary to the experience of the Americas. In addition, in the Americas, rubella eradication sustained the polio and measles achievements. How was this done? Countries of Latin America and the Caribbean (LAC) prioritized long-term strengthening of their country routine national immunization programs despite having short-term, targeted disease-specific goals. In so doing, they encountered new opportunities to expand the benefits of disease control and elimination activities to other aspects of public health, most importantly toward improving health care for women and newborns and reducing inequities in health in the region’s poorest communities. Implementation of similar strategies could lead to the global eradication of measles, rubella, and congenital rubella syndrome early this century, while strengthening routine immunization programs and developing the capacity to introduce new and underutilized vaccines. This chapter describes the historical perspective of measles and rubella eradication, the progress that has been achieved, and the implications for future benefits in both developed and developing countries. In this chapter, the term “eradication” will be used instead of “elimination” (cf. Cochi and Dowdle, this volume). Routine Immunization Strengthening national capacity to conduct effective routine national immunization programs was, and remains, the predominant driving force behind the eradication of polio, measles, and, more recently, rubella and congenital rubella syndrome. In 1993, in a review of cost-effective health measures, the World Bank concluded that measles vaccination was one of the most costeffective public health interventions currently available (World Bank 1993). This report was very timely, coming on the heels of polio eradication in the Americas. Although measles vaccine coverage through strengthened routine immunization programs markedly increased in the 1990s in the Americas, measles outbreaks continued to occur. Typically, several years of low measles incidence culminated in the occurrence of a large measles outbreak. Even in Measles and Rubella Eradication in the Americas 27 areas where high coverage rates had been achieved and maintained, outbreaks were reported (Bloch et al. 1985). In addition, both in countries of LAC and elsewhere, large measles outbreaks were reported where programs failed to achieve and maintain high levels of vaccination coverage (Clements and Cutts 1995). Moreover, some outbreaks were reported from countries that had developed strong systems for vaccine delivery and had achieved high measles vaccination coverage (Cutts and Markowitz 1994). Factors that have been implicated in these outbreaks...