Noroviruses as a major cause of acute gastroenteritis in children in Finland, 2009–2010

Abstract

Noroviruses are, after rotaviruses, the second most common cause of acute gastroenteritis in young children. In a prospective study conducted in 2009-2010 at the Tampere University Hospital, 195 stool specimens were collected from cases of acute gastroenteritis in children and examined for noroviruses, sapoviruses, and rotaviruses, using a reverse transcriptase polymerase chain reaction (RT-PCR). Noroviruses were found in 49 (25%) of the cases and sapoviruses in 12 (6%). The norovirus genotype GII.4 dominated with a 76% share; other genotypes detected were GII.7/GII.6 (16%), GII.g/GII.12, GII.e/GII.4, and GII.7 (2% each). For comparison, 47 (24%) cases of rotavirus gastroenteritis were diagnosed in the same period. In conclusion, after the introduction of rotavirus vaccination in Finland in September 2009, noroviruses have become as common as rotaviruses as the causative agents of acute gastroenteritis in young children, and are likely to become the leading cause. Norovirus GII.4 continues to be the dominant genotype.

Genotype Considerations for Virus-Like Particle-Based Bivalent Norovirus Vaccine Composition

“…4-1999 andGII.4-2010 NO belong to the same genotype, having approximately 95% homology in the VP1 capsid protein amino acid sequences (21,49), there is remarkable difference in the putative protective immune responses they induce. We demonstrated in this study that GII.4-1999 ancestor VLPs induced cross-blocking antibodies against distant and rare but recently reemerging GII NoV genotype GII.12 (23,50), as well as to GII.4 NO and to the most recent GII.4-2012 Sydney VLPs. On the contrary, GII.4 NO VLP immunization induced crossblocking antibodies only to closely related GII.4 Sydney.…”

Norovirus GII.17 Predominates in Selected Surface Water Sources in Kenya

“…The GII.6 strains were the second most predominant strains identified and clustered together with strains from Sweden (JN183165) and Japan (AB818398). After NoV GII.4, NoV GII.6 has been shown to be the second most dominant strain in clinical studies in a number of countries namely, SA, Brazil, Japan, and Finland (Phan et al 2005;Mans et al, 2010;Ferreira et al 2010;Puustinen et al 2011;Chan-it et al 2012). Norovirus GII.6 strains were previously identified in clinical specimens from Kenya (Mans et al 2014), indicating the presence of clinically relevant strains in the water sources.…”

Severe Viral Gastroenteritis in Children After Suboptimal Rotavirus Immunization in Taiwan

“…the g1 predominance (57.5%) in taiwan after rotavirus vaccination is consistent with a postvaccine investigation in Finland, with genotype g1 prevalence of 40%. 5 the reason for such change remains unknown. as to P-genotypes, there is similar distribution of P [4] and P [8] in the 2 periods.…”

“…4 However, in recent studies, norovirus has been increasingly recognized as the leading cause of epidemic gastroenteritis in humans and its importance is accentuated by its complex and rapid accumulation of genetic polymorphisms. 5,6 live-attenuated oral rotavirus vaccines prevent effectively severe rotavirus age but are less efficacious against mild rotavirus infection. 3 Field effectiveness of these vaccines in europe and the united States against severe age has been above 90% and in latin america around 80%.…”