Did Large-Scale Vaccination Drive Changes in the Circulating Rotavirus Population in Belgium?

Abstract

Vaccination can place selective pressures on viral populations, leading to changes in the distribution of strains as viruses evolve to escape immunity from the vaccine. Vaccine-driven strain replacement is a major concern after nationwide rotavirus vaccine introductions. However, the distribution of the predominant rotavirus genotypes varies from year to year in the absence of vaccination, making it difficult to determine what changes can be attributed to the vaccines. To gain insight in the underlying dynamics driving changes in the rotavirus population, we fitted a hierarchy of mathematical models to national and local genotype-specific hospitalization data from Belgium, where large-scale vaccination was introduced in 2006. We estimated that natural- and vaccine-derived immunity was strongest against completely homotypic strains and weakest against fully heterotypic strains, with an intermediate immunity amongst partially heterotypic strains. The predominance of G2P[4] infections in Belgium after vaccine introduction can be explained by a combination of natural genotype fluctuations and weaker natural and vaccine-induced immunity against infection with strains heterotypic to the vaccine, in the absence of significant variation in strain-specific vaccine effectiveness against disease. However, the incidence of rotavirus gastroenteritis is predicted to remain low despite vaccine-driven changes in the distribution of genotypes.

• Authors: Virginia E Pitzer, Joke Bilcke, Elisabeth Heylen, Forrest W Crawford, Michael Callens, Frank De Smet, Marc Van Ranst, Mark Zeller, Jelle Matthijnssens
• Journal: Scientific reports (Sci Rep) Vol. 5 Pg. 18585 (Dec 21 2015) ISSN: 2045-2322 [Electronic] England
• PMID: 26687288 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)

Chemical References

• Rotavirus Vaccines

Topics

• Belgium
• Genotype
• Humans
• Models, Theoretical
• Rotavirus (pathogenicity)
• Rotavirus Infections (epidemiology, virology)
• Rotavirus Vaccines (therapeutic use)
• Vaccination