Genotyping and molecular epidemiology of non polyomyelitic enteroviruses

Abstract

Nonpolio enteroviruses can be reliably identified with molecular and computer tools for taxonomic, diagnostic and epidemiologic purposes. Seroneutralization tests can efficiently be replaced by genotyping assays using the VP1 capsid protein encoding gene to identify enterovirus strains isolated in cell cultures. Genotyping showed the close genetic relatedness between human enterovirus serotypes and animal enteroviruses and also rhinoviruses currently classified in a separate genus within the Picornaviridae family. Enterovirus genotyping can be done prospectively within 2 to 5 days in a greater number of meningitis patients, using cerebrospinal fluid specimens and hence can help in providing a prompt response to health alert. In the molecular epidemiology of human enteroviruses, recent advances were made by investigating genetic diversity within individual serotypes (genotypes, lineages) and the patterns of circulation and transmission of virus variants involved in epidemics (echovirus 30, enterovirus 71). The observation of epidemiologic features such as the frequent viral immigration of strains from different geographical origins speaks in favour of developing molecular identification of enteroviruses. Recombinant enterovirus strains can also be identified by genotyping. Homologous recombination is a major contributor to the genetic diversity in enteroviruses. Molecular signatures of recombination events are observed in circulating strains, suggesting the occurrence of frequent co-infections during their circulation within the general population. The role of genetic recombination in the emergence of virus variants and its involvement in the epidemiology of human enteroviruses should be investigated.