Global immunization: status, progress, challenges and future

Vaccines have made a major contribution to public health, including the eradication of one deadly disease, small pox, and the near eradication of another, poliomyelitis.Through the introduction of new vaccines, such as those against rotavirus and pneumococcal diseases, and with further improvements in coverage, vaccination can significantly contribute to the achievement of the health-related United Nations Millennium Development Goals.The Global Immunization Vision and Strategy (GIVS) was developed by WHO and UNICEF as a framework for strengthening national immunization programmes and protect as many people as possible against more diseases by expanding the reach of immunization, including new vaccines, to every eligible person.This paper briefly reviews global progress and challenges with respect to public vaccination programmes.

The most striking recent achievement has been that of reduction of global measles mortality from an estimated 750,000 deaths in 2000 down to 197,000 in 2007. Global vaccination coverage trends continued to be positive. In 2007 most regions reached more than 80% of their target populations with three doses of DPT containing vaccines. However, the coverage remains well short of the 2010 goal on 90% coverage, particularly in the WHO region of Africa (estimated coverage 74%), and South-East Asia, (estimated coverage 69%). Elements that have contributed to the gain in immunization coverage include national multi-year planning, district-level planning and monitoring, re-establishment of outreach services and the establishment of national budget lines for immunization services strengthening.

Remaining challenges include the need to: develop and implement strategies for reaching the difficult to reach; support evidence-based decisions to prioritize new vaccines for introduction; strengthening immunization systems to deliver new vaccines; expand vaccination to include older age groups; scale up vaccine preventable disease surveillance; improve quality of immunization coverage monitoring and use the data to improve programme performance; and explore financing options for reaching the GIVS goals, particularly in lower-middle income countries.

Although introduction of new vaccines is important,this should not be at the expense of sustaining existing immunization activities. Instead the introduction of new vaccine introduction should be viewed as an opportunity to strengthen immunization systems, increase vaccine coverage and reduce inequities of access to immunization services.