title: Importation and outbreak of wild polioviruses from 2000 to 2014 and interruption of transmission in Cameroon.
abstract: Efficient implementation of the global eradication strategies consisting of Acute Flaccid Paralysis (AFP) surveillance and mass immunization campaigns led to interruption of indigenous wild poliovirus transmission in Cameroon in 1999.
  
  
  
  This study describes type 1 and type 3 wild poliovirus (WPV) importation, incidence, geographic distribution and control since the original interruption of transmission in Cameroon.
  
  
  
  Stool samples from AFP patients under the age of 15 years in Cameroon were collected nationwide and subjected to virus isolation on RD and L20B cell cultures. Resulting virus isolates were typed by intratypic differentiation (ITD) and analysis of the VP1 coding sequence of the viral genome. Surveillance data originating from Cameroon between 2000 and 2014 were considered for retrospective descriptive analyses.
  
  
  
  From 2003 to 2009, multiple WPV importation events from neighboring countries affected mainly in the northern regions of Cameroon but did not led to sustained local transmission. Throughout this period, 16 WPV1 and 5 WPV3 were detected and identified as members of multiple clusters within type-specific West Africa B genotypes (WEAF-B). In 2013-2014, a polio outbreak associated to a highly evolved ("orphan") WPV1 affected four southern regions of Cameroon.
  
  
  
  The appearance of highly evolved lineage of type 1 WPV suggests potential surveillance gap and underscore the need to maintain comprehensive polio immunization activities and sensitive surveillance systems in place as long as any country in the world remains endemic for WPV.
authors.affiliation: Virology Service, Centre Pasteur of Cameroon, P.O. Box 1274, Yaoundé, Cameroon.
authors.forename: Marie Claire
authors.initials: MC
authors.lastname: Endegue-Zanga
authors.affiliation: Virology Service, Centre Pasteur of Cameroon, P.O. Box 1274, Yaoundé, Cameroon.
authors.forename: Serge Alain
authors.initials: SA
authors.lastname: Sadeuh-Mba
authors.affiliation: Division of Viral Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA.
authors.forename: Jane
authors.initials: J
authors.lastname: Iber
authors.affiliation: Division of Viral Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA.
authors.forename: Cara C
authors.initials: CC
authors.lastname: Burns
authors.affiliation: National Institute for Communicable Diseases, Johannesburg, South Africa.
authors.forename: Nicksy Gumede
authors.initials: NG
authors.lastname: Moeletsi
authors.affiliation: Department of Medical Laboratory Science, College of Medical Sciences, University of Maiduguri, Maiduguri, Nigeria.
authors.forename: Marycelin
authors.initials: M
authors.lastname: Baba
authors.affiliation: Department of Microbiology, University of Maiduguri, Bama Road, P.M.B. 1069, Maiduguri, Nigeria.
authors.forename: David
authors.initials: D
authors.lastname: Bukbuk
authors.affiliation: Institut Pasteur, Biologie des Virus Entériques, INSERM U994, 75724 Paris, Cedex 15, France.
authors.forename: Francis
authors.initials: F
authors.lastname: Delpeyroux
authors.affiliation: WHO Cameroon Country Office, P.O. Box 155, Yaoundé, Cameroon.
authors.forename: Marcellin Nimpa
authors.initials: MN
authors.lastname: Mengouo
authors.affiliation: Virology Service, Centre Pasteur of Cameroon, P.O. Box 1274, Yaoundé, Cameroon.
authors.forename: Maurice
authors.initials: M
authors.lastname: Demanou
authors.affiliation: Virology Service, Centre Pasteur of Cameroon, P.O. Box 1274, Yaoundé, Cameroon.
authors.forename: Guy
authors.initials: G
authors.lastname: Vernet
authors.affiliation: The University of Yaoundé I, P.O. Box 337, Yaoundé, Cameroon.
authors.forename: François-Xavier
authors.initials: FX
authors.lastname: Etoa
authors.affiliation: Virology Service, Centre Pasteur of Cameroon, P.O. Box 1274, Yaoundé, Cameroon. Electronic address: njouom@pasteur-yaounde.org.
authors.forename: Richard
authors.initials: R
authors.lastname: Njouom
mesh_terms: D000293:Adolescent; D002163:Cameroon / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D004196:Disease Outbreaks; D018562:Disease Transmission, Infectious / Q000517:prevention & control*; D005243:Feces / Q000821:virology; D005260:Female; D005838:Genotype; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D011051:Poliomyelitis / Q000453:epidemiology* / Q000517:prevention & control / Q000635:transmission*; D017955:Poliovirus / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D012189:Retrospective Studies; D017422:Sequence Analysis, DNA; D019371:Topography, Medical; D014195:Travel
keywords: Eradication; Immunization; Importation; Poliomyelitis; Wild poliovirus