title: Switch from oral to inactivated poliovirus vaccine in Yogyakarta Province, Indonesia: summary of coverage, immunity, and environmental surveillance.
abstract: BACKGROUND
  Inactivated poliovirus vaccine (IPV) is rarely used in tropical developing countries. To generate additional scientific information, especially on the possible emergence of vaccine-derived polioviruses (VDPVs) in an IPV-only environment, we initiated an IPV introduction project in Yogyakarta, an Indonesian province. In this report, we present the coverage, immunity, and VDPV surveillance results.
  
  
  METHODS
  In Yogyakarta, we established environmental surveillance starting in 2004; and conducted routine immunization coverage and seroprevalence surveys before and after a September 2007 switch from oral poliovirus vaccine (OPV) to IPV, using standard coverage and serosurvey methods. Rates and types of polioviruses found in sewage samples were analyzed, and all poliovirus isolates after the switch were sequenced.
  
  
  RESULTS
  Vaccination coverage (>95%) and immunity (approximately 100%) did not change substantially before and after the IPV switch. No VDPVs were detected. Before the switch, 58% of environmental samples contained Sabin poliovirus; starting 6 weeks after the switch, Sabin polioviruses were rarely isolated, and if they were, genetic sequencing suggested recent introductions.
  
  
  CONCLUSIONS
  This project demonstrated that under almost ideal conditions (good hygiene, maintenance of universally high IPV coverage, and corresponding high immunity against polioviruses), no emergence and circulation of VDPV could be detected in a tropical developing country setting.
authors.affiliation: National Institute of Health and Research Development.
authors.forename: Gendro
authors.initials: G
authors.lastname: Wahjuhono
authors.affiliation: Yogyakarta Provincial Health Office.
authors.lastname: Revolusiana
authors.affiliation: National Polio Laboratory Biofarma, Bandung, Indonesia.
authors.forename: Dyah
authors.initials: D
authors.lastname: Widhiastuti
authors.affiliation: Ministry of Health, Jakarta.
authors.forename: Julitasari
authors.initials: J
authors.lastname: Sundoro
authors.affiliation: Yogyakarta Provincial Health Office.
authors.forename: Tri
authors.initials: T
authors.lastname: Mardani
authors.affiliation: Provincial Health Laboratory.
authors.forename: Woro Umi
authors.initials: WU
authors.lastname: Ratih
authors.affiliation: Department of Child Health, Faculty of Medicine, Gadjah Mada University, Yogyakarta.
authors.forename: Retno
authors.initials: R
authors.lastname: Sutomo
authors.affiliation: Department of Child Health, Faculty of Medicine, Gadjah Mada University, Yogyakarta.
authors.forename: Ida
authors.initials: I
authors.lastname: Safitri
authors.affiliation: Ministry of Health, Jakarta.
authors.forename: Ondri Dwi
authors.initials: OD
authors.lastname: Sampurno
authors.affiliation: World Health Organization, Country Office, Jakarta.
authors.forename: Bardan
authors.initials: B
authors.lastname: Rana
authors.affiliation: National Institute for Health and Welfare, Helsinki, Finland.
authors.forename: Merja
authors.initials: M
authors.lastname: Roivainen
authors.affiliation: World Health Organization, Geneva, Switzerland.
authors.forename: Anna-Lea
authors.initials: AL
authors.lastname: Kahn
authors.affiliation: World Health Organization, Geneva, Switzerland.
authors.forename: Ondrej
authors.initials: O
authors.lastname: Mach
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Pallansch
authors.affiliation: World Health Organization, Geneva, Switzerland.
authors.forename: Roland W
authors.initials: RW
authors.lastname: Sutter
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D002675:Child, Preschool; D004784:Environmental Monitoring; D005260:Female; D006801:Humans; D007214:Indonesia; D007223:Infant; D008297:Male; D011051:Poliomyelitis / Q000517:prevention & control*; D017955:Poliovirus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D011054:Poliovirus Vaccine, Inactivated / Q000008:administration & dosage* / Q000276:immunology*; D012722:Sewage / Q000821:virology*; D014611:Vaccination / Q000379:methods* / Q000706:statistics & numerical data
chemical_list: D000914:Antibodies, Viral; D011054:Poliovirus Vaccine, Inactivated; D012722:Sewage
keywords: immunization; polio; poliovirus circulation