Monovalent Rotavirus Vaccine Provides Protection Against an Emerging Fully Heterotypic G9P[4] Rotavirus Strain in Mexico

Epidemic Intelligence Service, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
The Journal of Infectious Diseases (Impact Factor: 5.78). 09/2011; 204(5):783-6. DOI: 10.1093/infdis/jir390
Source: PubMed

ABSTRACT After the introduction of monovalent rotavirus vaccine (RV1) in Mexico in 2006-2007, diarrhea mortality and morbidity declined substantially among Mexican children under 5 years of age. In January 2010, surveillance identified the emergence of a novel G9P[4] rotavirus strain nationwide. We conducted a case-control study to assess the field effectiveness of RV1 against severe rotavirus gastroenteritis caused by this unusual strain and to determine whether the G9P[4] emergence was related to vaccine failure or failure to vaccinate. RV1 was 94% effective (95% confidence interval, 16%-100%) against G9P[4] rotavirus-related hospitalization, indicating that its emergence was likely unrelated to vaccine pressure.

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