title: Molecular epidemiology of poliovirus infection in Tunisia.
abstract: This report is an overview of poliomyelitis surveillance in Tunisia from 1991 to 1996. In all, 2088 stool specimens, collected from 152 acute flaccid paralysis (AFP) cases and from 1747 of their healthy contacts were investigated. Virus isolation was done systematically in RD and HEp-2C cell lines and isolated viruses were typed by sero-neutralisation as polioviruses or non-polio enteroviruses. Poliovirus isolates were analysed systematically for their wild or vaccine-related origin by two methods--one based on antigenic differences and one on genetic differences between strains. All type 2 polioviruses were vaccine-related and most wild viruses belonged to polio serotype 3. Wild polio type 3 viruses were detected in 1991 and 1992 in six cases of paralytic polio. A silent circulation of wild polio 1 and wild polio 3 was detected in 1994. No wild virus was detected in Tunisia from 1995 onwards. Wild polioviruses were sequenced and compared with Tunisian wild strains isolated during the 1980s, as well as other genotypes from the international database. These investigations revealed a single Tunisian polio 3 genotype that has been circulating from 1985 to 1994 and two different polio 1 genotypes. These results reflect effective control strategies within the country and contribute to the improvement of the polio eradication programme effectiveness at national and global levels.
authors.affiliation: WHO Regional Reference Laboratory on Poliomyelitis, Institut Pasteur, Tunis, Tunisia.
authors.forename: H
authors.initials: H
authors.lastname: Triki
authors.affiliation: WHO Regional Reference Laboratory on Poliomyelitis, Institut Pasteur, Tunis, Tunisia.
authors.forename: O
authors.initials: O
authors.lastname: Bahri
authors.affiliation: Unite de Virologie Medicale, Institut Pasteur, Paris, France.
authors.forename: S
authors.initials: S
authors.lastname: Guillot
authors.affiliation: Laboratory of Virology, National Institute of Public Health and Environmental Protection (RIVM), Bilthoven, The Netherlands.
authors.forename: H G A M
authors.initials: HGAM
authors.lastname: VAN DER Avoort
authors.affiliation: WHO Regional Reference Laboratory on Poliomyelitis, Institut Pasteur, Tunis, Tunisia.
authors.forename: J
authors.initials: J
authors.lastname: Ben Sassi
authors.affiliation: WHO Regional Reference Laboratory on Poliomyelitis, Institut Pasteur, Tunis, Tunisia.
authors.forename: A
authors.initials: A
authors.lastname: Arrouji
authors.affiliation: Laboratoire de Microbiologie, Hôpital Charles Nicolle, Tunis, Tunisia.
authors.forename: Z
authors.initials: Z
authors.lastname: Arrouji
authors.affiliation: Laboratoire de Microbiologie, Hôpital Charles Nicolle, Tunis, Tunisia.
authors.forename: A
authors.initials: A
authors.lastname: Slim
authors.affiliation: Unite de Virologie Medicale, Institut Pasteur, Paris, France.
authors.forename: R
authors.initials: R
authors.lastname: Crainic
authors.affiliation: WHO Regional Reference Laboratory on Poliomyelitis, Institut Pasteur, Tunis, Tunisia.
authors.forename: K
authors.initials: K
authors.lastname: Dellagi
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004770:Enterovirus / Q000302:isolation & purification; D005243:Feces / Q000821:virology; D005838:Genotype; D006801:Humans; D007223:Infant; D017720:Molecular Epidemiology; D009123:Muscle Hypotonia; D010243:Paralysis / Q000821:virology; D011051:Poliomyelitis / Q000453:epidemiology* / Q000821:virology; D017955:Poliovirus / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D012703:Serotyping; D014416:Tunisia / Q000453:epidemiology