title: Group A rotavirus genotypes circulating prior to implementation of a National Immunization Program in Estonia.
abstract: Group A rotaviruses (RVA) are a major cause of acute gastroenteritis in children ≤ 5 y worldwide which could be prevented with two recently introduced vaccines - monovalent Rotarix (live-attenuated G1P[8] strain) and pentavalent RotaTeq (human-bovine reassortant containing serotypes G1, G2, G3, G4 and P[8]). Prior to implementation of vaccines into national immunization program we aimed to describe RVA genotype distribution in hospitalized children aged < 5 y in Estonia during 2007-2008. A total of 671 children with confirmed RVA gastroenteritis from three major pediatric hospitals were prospectively enrolled. G- and P-genotypes were detected from 124 stool samples by semi-nested reverse transcription-PCR. Severity of disease was assessed using Clark scoring system. The majority of cases (65%) occurred in infants aged 7 to 24 mo and were of moderate severity (mean Clark score 12.1 (SD 3.2)). The prevailing strain was G2P[4] (34.7%), causing significantly more cases than G4P[8] (12.9%), G1P[8] or G9P[8] (both 4.0%), G3P[8] (1.6%). Yearly differences in genotype distribution occurred, as G2P[4] (52.8%) dominated in 2007, but G4P[8] (26.9%) in 2008. One third of strains remained non-typeable. The distribution of RVA genotypes in Estonia differs from that seen in other Central and Eastern European countries, although one should bear in mind the large proportion of P-untypeable strains and natural fluctuations of dominating RVA genotypes. Nevertheless, considering the high genotype-independent efficacy of the vaccines, introduction of national immunization should be considered.
authors.affiliation: Department of Microbiology, University of Tartu, Tartu, Estonia. hiie.soeorg@ut.ee
authors.forename: Hiie
authors.initials: H
authors.lastname: Soeorg
authors.forename: Eda
authors.initials: E
authors.lastname: Tamm
authors.forename: Kristi
authors.initials: K
authors.lastname: Huik
authors.forename: Merit
authors.initials: M
authors.lastname: Pauskar
authors.forename: Dagmar
authors.initials: D
authors.lastname: Mägi
authors.forename: Kristiine
authors.initials: K
authors.lastname: Pruudel
authors.forename: Lehi
authors.initials: L
authors.lastname: Vainomäe
authors.forename: Leelo
authors.initials: L
authors.lastname: Moosar
authors.forename: Kaisa
authors.initials: K
authors.lastname: Kirss
authors.forename: Siiri
authors.initials: S
authors.lastname: Torm
authors.forename: Margit
authors.initials: M
authors.lastname: Närska
authors.forename: Aime
authors.initials: A
authors.lastname: Pütsepp
authors.forename: Helke
authors.initials: H
authors.lastname: Nurm
authors.forename: Kaie
authors.initials: K
authors.lastname: Pruunsild
authors.forename: Ave
authors.initials: A
authors.lastname: Jänes
authors.forename: Kai
authors.initials: K
authors.lastname: Zilmer
authors.forename: Irja
authors.initials: I
authors.lastname: Lutsar
mesh_terms: D002673:Child, Hospitalized; D002675:Child, Preschool; D004957:Estonia / Q000453:epidemiology; D005243:Feces / Q000821:virology; D005260:Female; D005759:Gastroenteritis / Q000453:epidemiology* / Q000473:pathology / Q000821:virology*; D005838:Genotype; D006801:Humans; D007223:Infant; D008297:Male; D017720:Molecular Epidemiology; D016133:Polymerase Chain Reaction / Q000379:methods; D015995:Prevalence; D011446:Prospective Studies; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D012401:Rotavirus / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D012400:Rotavirus Infections / Q000453:epidemiology* / Q000473:pathology / Q000821:virology*; D012720:Severity of Illness Index