Commentary: The Unfolding Story of Global Poliomyelitis Eradication

Abstract

Captured in the pages of this supplement of the Journal of Infectious Diseases is a glimpse of the tremendous progress that has occurred since the global polio eradication initiative was launched by the World Health Assembly (WHA) in 1988. Drawing inspiration from the successful smallpox initiative, the WHA resolved to eradicate polio from the world by the year 2000 [1]. As was the case with smallpox virus, poliovirus causes acute, nonpersistent infections; humans are the only reservoir; virus survival in the environment is finite; and immunization with vaccine interrupts virus transmission?collectively, these factors make poliovirus a candidate for eradication. Poliovirus is on target to become only the second virus in the history of humankind to be eradicated from the face of the earth. The World Health Organization (WHO) is leading a global partnership of international organizations and governments to implement the proven strategies for polio eradication in all remaining polio-endemic countries [2]. From 1988 through 1995, reported cases of paralytic polio declined by 8007o, from 35,251 cases in 1988 to 7024 cases in 1995 [3, 4]; preliminary data for 1996 suggest a further decrease by ^O07o compared with 1995. One of the key strategies for polio eradication is the administration of supplemental doses of oral poliovirus vaccine (OPV) during nationwide mass campaigns known as National Immunization Days (NIDs) [2]. NIDs provide two supplemental doses of OPV to all young children (generally those ^ years of age), regardless of their previous immunization status. The two rounds of NIDs are each conducted over a short period, usually 1-3 days, during the low season for poliovirus transmission, with an interval of 4-6 weeks between rounds. These mass