Global public health mandates in a diverse world: the polio eradication initiative and the expanded programme on immunization in sub-Saharan Africa and South Asia.

BACKGROUND: The circulation of wild poliovirus is expected to cease soon due to the success of the global polio eradication initiative. Thereafter, intensified polio eradication efforts such as National Immunisation Days (NIDs) will most likely be discontinued. As a consequence, the expanded programme on immunization (EPI) will no longer enjoy extra inputs from the polio eradication initiative. We investigated whether today's EPIs are ensuring universal and equitable vaccine coverage; and whether the removal of extra inputs associated with the implementation of NIDs is likely to affect EPI coverage and equity.

METHODS: Using data from Demographic and Health Surveys conducted in 15 countries of South Asia and Africa during 1990-2001, we examined absolute levels of EPI coverage; changes in EPI coverage after the introduction of NIDs; and relative coverage according to urban versus rural residence, higher versus lower education of mothers, and wealthiest vs. poorest population segment.

RESULTS: Polio and non-polio antigen coverage increased in seven countries during the study period. Substantial inequalities in coverage of non-polio antigens persist, however, translating into inequities in the risk of contracting vaccine preventable diseases. In some African countries, routine EPI coverage and/or equity declined during the study period. In these countries, any positive effect of NIDs on the EPI coverage must have been small, relative to the negative effects of declining economies or deteriorating health systems. In Nigeria, Zimbabwe, Kenya and Malawi, even polio coverage declined, in spite of the introduction of NIDs.

CONCLUSION: As additional inputs associated with polio eradication will cease, routine EPI services need to be strengthened substantially in order to maintain levels of population immunity against polio and to improve social equity in the coverage of non-polio EPI antigens. Our findings imply that this aim will require additional inputs, particularly in African countries.