title: Changing molecular epidemiology of rotavirus infection after introduction of monovalent rotavirus vaccination in Scotland.
abstract: Rotaviruses (RV) are the leading cause of gastroenteritis in children less than five years of age worldwide. Rotarix®, a live attenuated monovalent vaccine containing a RV strain of G1P[8] specificity has been included in the childhood immunisation schedule from June 2013 in Scotland. This study aimed to characterise the prevalent RV strains in Scotland before and after the introduction of the RV vaccine.
  
  
  
  RV positive faecal samples from Scottish virology laboratories covering the years 2012-2015 were genotyped. Viral RNA was extracted from faecal suspensions. VP7 and VP4 gene specific primers were used for multiplex hemi-nested PCRs and sequencing. Mann-Whitney U test and Chi-square test were used for statistical comparison.
  
  
  
  There was a decrease in RV positive samples from the Scottish virology laboratories from 7409 samples in the pre-vaccination years (2009-2013) to 760 in 2014-2015, with an annual reduction of RV infections by 74.4% (RR-3.95; 95%-CI, 3.53-4.42, p<0.001). 362 samples from the pre-vaccination period and 278 samples from the post-vaccination were genotyped. There was a drop in prevalence of G1P[8] strains (72.1%, 95%-CI, 67.42-76.33 to 15%, 95%-CI, 11.38-19.79) after introduction of the vaccine. In the post-vaccination period G2P[4] was the dominant strain in Scotland (21.9%, 95%-CI, 17.48-27.17) with increase in G9P[8] (12.9%, 95%-CI, 9.50-7.41), G12P[8] (12.2%, 95%-CI, 8.89-16.60) and G3P[8] (11.9%, 95%-CI, 8.58-16.20) infections. Phylogenetic analysis of the VP7 and VP4 genes showed no major differences between the pre and post-vaccination G1P[8] strains.
  
  
  
  This laboratory based surveillance study shows significant reduction in reported RV cases and a shift in proportion from G1P[8] to G2P[4] strains after introduction of RV vaccination in Scotland. The genotyping data from a subset of the total reported RV cases will be used to ascertain cross protection against strains and identify vaccine induced RV strain shifts in the years to come.
authors.affiliation: Gastrointestinal Research Group, Institute of Medical Sciences, University of Aberdeen, Aberdeen AB25 2ZD, UK. Electronic address: indrani.mukhopadhya@abdn.ac.uk.
authors.forename: Indrani
authors.initials: I
authors.lastname: Mukhopadhya
authors.affiliation: Vaccine Preventable Diseases, NHS National Services Scotland, Health Protection Scotland, Glasgow G2 6QE, UK.
authors.forename: Heather
authors.initials: H
authors.lastname: Murdoch
authors.affiliation: Gastrointestinal Research Group, Institute of Medical Sciences, University of Aberdeen, Aberdeen AB25 2ZD, UK.
authors.forename: Susan
authors.initials: S
authors.lastname: Berry
authors.affiliation: Virology Laboratory, Department of Medical Microbiology, Aberdeen Royal Infirmary, Aberdeen AB25 2ZD, UK.
authors.forename: Alison
authors.initials: A
authors.lastname: Hunt
authors.affiliation: Institute of Infection and Global Health, University of Liverpool, Liverpool, UK.
authors.forename: Miren
authors.initials: M
authors.lastname: Iturriza-Gomara
authors.affiliation: Vaccine Preventable Diseases, NHS National Services Scotland, Health Protection Scotland, Glasgow G2 6QE, UK.
authors.forename: Alison
authors.initials: A
authors.lastname: Smith-Palmer
authors.affiliation: Vaccine Preventable Diseases, NHS National Services Scotland, Health Protection Scotland, Glasgow G2 6QE, UK.
authors.forename: J Claire
authors.initials: JC
authors.lastname: Cameron
authors.affiliation: Gastrointestinal Research Group, Institute of Medical Sciences, University of Aberdeen, Aberdeen AB25 2ZD, UK.
authors.forename: Georgina L
authors.initials: GL
authors.lastname: Hold
mesh_terms: D000956:Antigens, Viral / Q000235:genetics; D036022:Capsid Proteins / Q000235:genetics; D002675:Child, Preschool; D005243:Feces / Q000821:virology; D005260:Female; D005838:Genotype; D060005:Genotyping Techniques; D006801:Humans; D017589:Immunization Programs; D007223:Infant; D008297:Male; D017720:Molecular Epidemiology; D016133:Polymerase Chain Reaction; D015995:Prevalence; D012401:Rotavirus / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D012400:Rotavirus Infections / Q000453:epidemiology* / Q000517:prevention & control / Q000821:virology*; D022243:Rotavirus Vaccines / Q000008:administration & dosage / Q000276:immunology*; D012606:Scotland / Q000453:epidemiology; D017422:Sequence Analysis, DNA; D014611:Vaccination / Q000706:statistics & numerical data; D014613:Vaccines, Attenuated / Q000008:administration & dosage / Q000276:immunology
chemical_list: D000956:Antigens, Viral; D036022:Capsid Proteins; C492457:RIX4414 vaccine; D022243:Rotavirus Vaccines; C060339:VP4 protein, Rotavirus; C050779:VP7 protein, Rotavirus; D014613:Vaccines, Attenuated
keywords: Genotyping; Rotarix®®; Rotavirus; Rotavirus vaccine; Scotland