Mechanism of Poliovirus Eradication

Olen M. Kew; Mark A. Pallansch

doi:10.1128/9781555817916.ch39

Chapter 39 : Mechanism of Poliovirus Eradication

Authors: Olen M. Kew¹, Mark A. Pallansch²

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Affiliations: 1: Division of Viral and Rickettsial Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, 1600 Clifton Rd., Mailstop G-10, Atlanta, GA 30333; 2: Division of Viral and Rickettsial Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, 1600 Clifton Rd., Mailstop G-17, Atlanta, GA 30333

Content Type: Monograph

Publication Year: 2002

Category: Viruses and Viral Pathogenesis

Book DOI: 10.1128/9781555817916

Chapter DOI: 10.1128/9781555817916.ch39

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Abstract:

Systematic international efforts to eradicate polio from the developing world began in the Americas in 1985, when the Pan American Health Organization (PAHO) declared a target date of 1990 for the eradication of polio throughout the Americas. Surveillance for wild polioviruses has two arms: (i) acute flaccid paralysis (AFP) case investigations and (ii) virologic studies of polioviruses obtained from clinical specimens. AFP surveillance by itself is neither highly specific nor highly sensitive for detecting individual wild poliovirus infections. Poliovirus eradication has achieved the elimination of individual lineages (equivalent to chains of transmission), different genotypes (groups of related lineages sharing >85% nucleotide sequence identity), and probably wild poliovirus type 2. Polio cases associated with these importations have revealed pockets of unimmunized children in the new host areas, prompting local immunization responses. However, by far the most effective response is to eliminate the source reservoirs. Various supplementary approaches are implemented to monitor ongoing laboratory performance. A serious challenge to the integrity of poliovirus surveillance data is the occurrence of poliovirus contamination of cultures. Recently, polio outbreaks associated with circulating vaccine-derived poliovirus (cVDPV) have been recognized in three different parts of the world. The occurrence of iVDPVs and cVDPVs appears to be rare. Moreover, most chronic poliovirus excretors in developed countries spontaneously stop shedding or die of complications from their immunodeficiency. As an increasing number of highly developed countries have switched to inactivated polio vaccine (IPV), the chances for the occurrence of new iVDPV infections have decreased.

Citation: Kew O, Pallansch M. 2002. Mechanism of Poliovirus Eradication, p 481-491. In Semler B, Wimmer E (ed), Molecular Biology of Picornavirus. ASM Press, Washington, DC. doi: 10.1128/9781555817916.ch39

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Mechanism of Poliovirus Eradication

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FIGURE 1

Countries with indigenous wild poliovirus circulation (shaded) in 1988, 1998, and 2001

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FIGURE 1

Countries with indigenous wild poliovirus circulation (shaded) in 1988, 1998, and 2001

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FIGURE 3

Trees of VP1 sequence relationships among representative isolates of surviving type 1 poliovirus genotypes.

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FIGURE 3

Trees of VP1 sequence relationships among representative isolates of surviving type 1 poliovirus genotypes.

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FIGURE 4

Trees of VP1 sequence relationships among representative isolates of surviving type 3 poliovirus genotypes.

10.1128/9781555817916/fig39-4_thmb.gif

10.1128/9781555817916/fig39-4.gif

FIGURE 4

Trees of VP1 sequence relationships among representative isolates of surviving type 3 poliovirus genotypes.

/content/10.1128/9781555817916.chap39.fig39-2

FIGURE 2

Progressive eradication of wild poliovirus genotypes, 1988 to 2001. Stop signs indicate the year and location where the last isolate was obtained for each extinct genotype.

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10.1128/9781555817916/fig39-2.gif

FIGURE 2

Progressive eradication of wild poliovirus genotypes, 1988 to 2001. Stop signs indicate the year and location where the last isolate was obtained for each extinct genotype.

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FIGURE 5

Trees showing long-range importation and cross-border transmission of wild type 1 poliovirus lineages, 1999 to 2001. The VP1 sequence of the Bulgaria isolate was kindly provided by Lucia Fiore.

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10.1128/9781555817916/fig39-5.gif

FIGURE 5

Trees showing long-range importation and cross-border transmission of wild type 1 poliovirus lineages, 1999 to 2001. The VP1 sequence of the Bulgaria isolate was kindly provided by Lucia Fiore.

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