In order to assess the level of polio virus with natural recombinant
genome and wild polio virus circulating in the environment of healthy
children aged 0 to 5 years in Abidjan, 130 polio viruses made up of 26
polio type 1, 55 type 2 and 49 type 3 were identified by neutralisation
test with monoclonal antibodies and restriction fragment length
polymorphism (RFLP) targeting the VP1 and 3D1 gene. Four wild non
Sabin-like (NSL) strains (3.1%): one type 2 and three type 3 were
identified in non vaccinated children. One hundred and six (81.5%)
isolates were Sabin-like, 20 (15.4%) were recombinant with the
following polio virus profiles: 2 Sabin-like type 1/type 2, 3
Sabin-like type 3/type 1, 11 Sabin-like type 3/type 2 and one polio
virus type 3 NSL/Sabin-like type 3. Intertypic vaccine/vaccine or
vaccine/wild strain recombinant polio virus circulating among healthy
children rate was high and suggested the need for a molecular
surveillance of vaccine strains. Oral Polio Vaccine (OPV) strains are
well-known to revert to pathogenicity in vaccines. Therefore, the long
term excretion of pathogenic OPV derived strains by some vaccinees
needs to be considered quite seriously. It therefore suggested that all
polio virus isolated from acute flaccid paralysis (AFP) be analyzed by
restriction fragment length polymorphism and sequencing of the viral
genome
