Dataset Information

Interpreting changes in measles genotype: the contribution of chance, migration and vaccine coverage.

ABSTRACT:

Background

In some populations, complete shifts in the genotype of the strain of measles circulating in the population have been observed, with given genotypes being replaced by new genotypes. Studies have postulated that such shifts may be attributable to differences between the fitness of the new and the old genotypes.

Methods

We developed a stochastic model of the transmission dynamics of measles, simulating the effects of different levels of migration, vaccination coverage and importation of new genotypes on patterns in the persistence and replacement of indigenous genotypes.

Results

The analyses illustrate that complete replacement in the genotype of the strain circulating in populations may occur because of chance. This occurred in >50% of model simulations, for levels of vaccination coverage and numbers of imported cases per year which are compatible with those observed in several Western European populations (>80% and >3 per million per year respectively) and for the given assumptions in the model.

Conclusion

The interpretation of genotypic data, which are increasingly being collected in surveillance programmes, needs to take account of the underlying vaccination coverage and the level of the importation rate of measles cases into the population.

SUBMITTER: Nojiri S

PROVIDER: S-EPMC2346460 | biostudies-literature | 2008 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Interpreting changes in measles genotype: the contribution of chance, migration and vaccine coverage.

Nojiri Shuko S Vynnycky Emilia E Gay Nigel N

BMC infectious diseases 20080411

<h4>Background</h4>In some populations, complete shifts in the genotype of the strain of measles circulating in the population have been observed, with given genotypes being replaced by new genotypes. Studies have postulated that such shifts may be attributable to differences between the fitness of the new and the old genotypes.<h4>Methods</h4>We developed a stochastic model of the transmission dynamics of measles, simulating the effects of different levels of migration, vaccination coverage and ...[more]

PMID: 18405360

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Dataset Information

Interpreting changes in measles genotype: the contribution of chance, migration and vaccine coverage.

Background

Methods

Results

Conclusion

Publications

Interpreting changes in measles genotype: the contribution of chance, migration and vaccine coverage.

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