Molecular epidemiology of norovirus infections in Stockholm, Sweden, during the years 2000 to 2003: association of the GGIIb genetic cluster with infection in children.
The incidence of norovirus-associated gastroenteritis and the molecular epidemiology of norovirus strains were studied during three seasons (2000-2001, 2001-2002, and 2002-2003) among patients of all ages, mainly from the Stockholm region in Sweden. A total of 3,252 fecal samples were analyzed by reverse transcription-PCR. The incidences of norovirus infection among adults were 23, 26, and 30% during the three seasons studied and 18, 11, and 15% among children 0 to 15 years of age. During the first season, all norovirus strains detected by PCR were typed either by reverse line blot hybridization or nucleotide sequence analysis. During the two successive seasons, a total of 60 norovirus-positive strains from the beginning, peak, and end of the seasons were selected for nucleotide sequence analysis. We identified two dominant norovirus variants over the seasons: a new norovirus variant, recently described as the GGIIb genetic cluster, dominated among children during the first season, and during the following two seasons, a GGII-4 variant dominated. Our data suggest that norovirus infections are common, not only among adults, but also among children, and that some strains may predominantly affect children.
Lindell
Annika Tiveljung
AT
Department of Clinical Microbiology, Karolinska University Hospital, Solna, SE-171 76 Stockholm, Sweden. annika.tiveljung-lindell@karolinska.se
Grillner
Lena
L
Svensson
Lennart
L
Wirgart
Benita Zweygberg
BZ
D000293:Adolescent; D001483:Base Sequence; D017250:Caliciviridae Infections / Q000453:epidemiology*; D002648:Child; D002675:Child, Preschool; D004196:Disease Outbreaks; D005759:Gastroenteritis / Q000453:epidemiology*; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008969:Molecular Sequence Data; D029322:Norovirus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D012621:Seasons; D013548:Sweden / Q000453:epidemiology; D013997:Time Factors