"Concerning poliovirus eradication, one should remember that it has been shown
that this virus can establish persistent infections."
A decade ago it has been first observed that poliovirus establishes persistent
infections in human cells of neuronal origin (Proc. Natl. Acad. Sci. USA,
1989, 86, 7590). Moreover, during these persistent infections, mutant
polioviruses are selected, and these mutants have acquired the capacity to
establish persistent infections in other cell types. Indeed, very few
mutations are sufficient to confer this new phenotype. This means that
poliovirus excreted by an infected human being, or a virus stock in the
laboratory, may contain such mutants because of the heterogeneous nature of
the poliovirus genome.
Moreover, in a murine model, the evolution of paralytic poliomyelitis
has been studied and it has been shown that poliovirus persists in the
central nervous system of mice for at least 12 months after the onset
of acute disease (J. Virol., 1997, 71, 1621).
Finally, the results of other groups have revealed the persistence of
poliovirus sequences in the central nervous system of some post-polio
patients (see: The post-polio syndrome; Advances in the pathogenesis and
treatment, Annals of the New York Academy of Sciences, vol. 753).
One should also not forget a possible poliovirus maintenance in nature, in
deep ice, where important human migrations have occurred."
Bruno Blondel, Florence Colbère-Garapin, Thérèse Couderc, Sophie Girard,
Florence Guivel-Benhassine, Sébastien Jacques, Nicole Pavio, Isabelle
Pelletier.
Unité de Neurovirologie
et Régénération du Système Nerveux
Institut Pasteur
28 Rue du Docteur Roux
75724 PARIS CEDEX 15
FRANCE