OPV strains circulation in HIV infected infants after National Immunisation Days in Bangui, Central African Republic.
BACKGROUND
Humans are the only host of polioviruses, thus the prospects of global polio eradication look reasonable. However, individuals with immunodeficiencies were shown to excrete vaccine derived poliovirus for long periods of time which led to reluctance to prolong the vaccination campaign for fear of this end result. Therefore, we aimed to assess the duration of excretion of poliovirus after the 2001 National Immunization Days according to Human immunodeficiency virus status.


RESULTS
Fifty three children were enrolled. Sequential stool samples were collected in between National Immunisation Days rounds and then every month during one year. Children were classified into 2 groups: no immunodepression (n = 38), immunodepression (n = 15) according to CD4+ lymphocytes cells count. Thirteen poliovirus strains were isolated from 11 children: 5 Human immunodeficiency virus positive and 6 Human immunodeficiency virus negative. None of the children excreted poliovirus for more than 4 weeks. The restriction fragment length polymorphism analysis showed that all strains were of Sabin origin including a unique Polio Sabine Vaccine types 2 and 3 (S2/S3) recombinant.


CONCLUSIONS
From these findings we assume that Human immunodeficiency virus positive children are not a high risk population for long term poliovirus excretion. More powerful studies are needed to confirm our findings.
Manirakiza
Alexandre
A
Virology Unit, Institut Pasteur de Bangui, Avenue Pasteur, BP 923, Bangui, Central African Republic. ionela512@yahoo.fr.
Picard
Emmanuella
E
Ngbale
Richard
R
Menard
Didier
D
Gouandjika-Vasilache
Ionela
I