Case-Control Evaluation of the Effectiveness of the G1P[8] Human Rotavirus Vaccine during an Outbreak of Rotavirus G2P[4] Infection in Central Australia

• Published in: Clinical infectious diseases Vol. 52; no. 2; pp. 191 - 199
• Main Authors: Snelling, T. L., Andrews, R. M., Kirkwood, C. D., Culvenor, S., Carapetis, J. R.
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 15.01.2011
• Subjects: ARTICLES AND COMMENTARIES; Australia - epidemiology; Biological and medical sciences; Case-Control Studies; Children; Clinical medicine; Disease Outbreaks; Dosage; Epidemics; Female; Gastroenteritis; Genotype; Hospitalization; Hospitalization - statistics & numerical data; Humans; Immunization; Infant; Infections; Infectious diseases; Male; Medical sciences; Rotavirus; Rotavirus - classification; Rotavirus - genetics; Rotavirus - isolation & purification; Rotavirus Infections - epidemiology; Rotavirus Infections - prevention & control; Rotavirus vaccines; Rotavirus Vaccines - administration & dosage; Rotavirus Vaccines - immunology; Vaccination; Vaccines; Viral diseases; Viruses; Australia; Oceania; Epidemic; Rotavirus; Human rotavirus; Gastroenteritis; Check; Vaccine; Reoviridae; Infection; Virus; Prevention; Immunoprophylaxis; Viral disease; Digestive diseases; Intestinal disease; Gastric disease
• ISSN: 1058-4838; 1537-6591
• DOI: 10.1093/cid/ciq101

The human rotavirus vaccine was evaluated during an outbreak of rotavirus G2P[4] infection in central Australia. No overall protective effect against hospitalization was demonstrated, raising concerns over the durability of vaccine protection against heterotypic strains. Background. Two and a half years after commencing routine vaccination with human rotavirus vaccine, an outbreak of rotavirus G2P[4] infection occurred in central Australia. Vaccine effectiveness against a P[8]-containing strain (G9P[8]) had been demonstrated previously in this setting. This subsequent outbreak provided the opportunity to evaluate vaccine effectiveness against hospitalizations for a non–vaccine-related genotype in the same population. Methods. A case-control study was nested within a cohort of vaccine-eligible children listed on a population-based immunization register. Children with rotavirus-confirmed gastroenteritis were individually matched by date of birth and Indigenous status with 4 control subjects. Results. Forty-one cases met the inclusion criteria, and 21 were severe cases among infants aged <12 months. Nineteen (46%) of 41 case patients had received 2 doses of human rotavirus vaccine, compared with 87 (53%) of 164 control subjects. Vaccine effectiveness against rotavirus-related hospitalization was 19% (odds ratio, .81; 95% confidence interval, .32–2.05) for 2 doses compared with none. On secondary analysis, there was evidence of a protective effect against disease complicated by acidosis in the subset of infants aged <12 months (odds ratio, .15; 95% confidence interval, .03–.84). Conclusions. Evidence was not found for an overall protective effect of human rotavirus vaccine against hospitalization for rotavirus disease in this setting. Post hoc analyses suggested a protective effect against severe disease in young infants.