Rotavirus genotype and Vesikari score of outpatients in Japan in the vaccine era

Pediatr Int. 2020 May;62(5):569-575. doi: 10.1111/ped.14150. Epub 2020 Apr 17.

Abstract

Background: Group A rotaviruses (RVs) are a major cause of severe gastroenteritis among infants and young children. In Japan, RV vaccines were introduced in 2011, leading to a reduction in severe gastroenteritis cases. Studies are required to assess the effectiveness of the vaccines and their effect on the prevalence of RV genotypes.

Methods: Fecal samples were collected from outpatients with RV gastroenteritis in a pediatric clinic in Sapporo, Japan, from 2010 to 2016. GPI genotypes were determined using reverse-transcription polymerase chain reaction. Clinical information and immunization records were obtained from outpatients after 2013. GPI genotypes and clinical features were compared between patients with and without a RV vaccine history.

Results: In total, 270 cases were genotyped. G1P[8]I1 (Wa-like G1P[8]) strains were dominant from 2010 to 2012. G1P[8]I2 (DS-1-like G1P[8]) strains appeared in 2012 and dominated in 2013 to 2015. G2P[4]I2 and G9P[8]I1 strains increased every 3 years (G2P[4]I2: 2011 and 2014, G9P[8]I1: 2010, 2013 and 2016). After the 2013 season, 137 cases were collected, 24 of which were vaccinated. Cases requiring drip infusion were fewer in the vaccination group than in the non-vaccination group (16.7% vs 52.2%). No patients required hospitalization in the vaccination group compared with 10.6% in the non-vaccination group. A severe Vesikari score was less common in the vaccination group than in the non-vaccination group (33.3% vs 78.8%). There was no significant difference in the GPI genotype distribution between the two groups.

Conclusion: Rotaviruses vaccine effectiveness, regardless of GPI genotype, was confirmed in terms of alleviation of disease severity.

Keywords: GPI genotype; Vesikari score; gastroenteritis; rotavirus; vaccination.

MeSH terms

  • Child, Preschool
  • Feces / virology
  • Female
  • Gastroenteritis / epidemiology*
  • Gastroenteritis / prevention & control
  • Gastroenteritis / virology*
  • Genotype
  • Humans
  • Infant
  • Japan
  • Male
  • Outpatients
  • RNA, Viral / genetics
  • Reverse Transcriptase Polymerase Chain Reaction / methods
  • Rotavirus / genetics*
  • Rotavirus Infections / epidemiology*
  • Rotavirus Infections / prevention & control
  • Rotavirus Infections / virology
  • Rotavirus Vaccines / therapeutic use*
  • Vaccination

Substances

  • RNA, Viral
  • Rotavirus Vaccines