title: Group A rotaviruses in children with gastroenteritis in a Canadian pediatric hospital: The prevaccine era.
abstract: BACKGROUND
  A publicly funded, group A rotavirus (RVA) vaccination program was implemented in Quebec in November 2011.
  
  
  OBJECTIVE
  To evaluate trends in RVA infections and describe circulating genotypes before the implementation of a publicly funded vaccination program.
  
  
  METHODS
  The Montreal Children's Hospital (Montreal, Quebec) virology laboratory database was reviewed for RVA ELISA performed between July 2006 and June 2011. A five-week moving average was used to follow the proportion of positive RVA ELISA test results. A season was defined as starting with the first two and ending with the final two consecutive weeks in which the percentage of specimens testing positive for RVA was ≥10%. Duplicate tests were excluded. A random sample of 39 RVA-positive fecal samples from the final season (2010/2011) was genetically characterized: VP4, VP6, VP7 and NSP4 gene segments were genotyped using sequence analysis.
  
  
  RESULTS
  Of the 3403 nonduplicate tests, 433 were RVA positive: 15.1% (2006/2007) to 9.3% (2010/2011) of the samples were positive during the study period, with a proportionally larger decrease in the percentage of positive tests compared with the decrease in the number of tests performed. The most common RVA strain types detected were G9P[8]I1 (n=19) and G1P[8]I1 (n=14), followed by G2P[4]I2 (n=4), G3P[6]I1 (n=1) and G4P[8]I2 (n=1). Mixed RVA infection was observed in two samples.
  
  
  CONCLUSIONS
  Before the implementation of the vaccination program, the proportion of positive RVA tests had already begun to steadily decline. The present study was the first to report the genetic makeup of human RVA collected from a Canadian hospital based on the genotyping of four gene segments. The present study provided a baseline with which to monitor the impact of the universal vaccination program.
authors.affiliation: Infectious Disease Division, Department of Pediatrics and Medical Microbiology, The Montreal Children's Hospital, McGill University, Montreal;
authors.forename: Estelle
authors.initials: E
authors.lastname: Chetrit
authors.affiliation: Canadian Food Inspection Agency, St Hyacinthe Laboratory, St Hyacinthe;
authors.forename: Yvan
authors.initials: Y
authors.lastname: L'homme
authors.affiliation: Canadian Food Inspection Agency, St Hyacinthe Laboratory, St Hyacinthe;
authors.forename: Jagdip Singh
authors.initials: JS
authors.lastname: Sohal
authors.affiliation: Infectious Disease Division, Department of Pediatrics and Medical Microbiology, The Montreal Children's Hospital, McGill University, Montreal; ; Department of Epidemiology and Biostatistics, McGill University, Montreal, Quebec.
authors.forename: Caroline
authors.initials: C
authors.lastname: Quach
keywords: Epidemiology; Genotyping; Rotavirus; Sequencing