[Molecular-genetic characteristic of astroviruses circulating in Nizhny Novgorod].

AIM

Genotyping ofastroviruses isolated from children with acute enteric infection (AEI) on the territory of Nizhny Novgorod in 2006 - 2011.

MATERIALS AND METHODS

Samples of feces from children hospitalized in intestine infection department of a Nizhny Novgorod infectious diseases hospitals served as study material. Astroviruses were detected by reverse transcription polymerase chain reaction method. Astrovirus genotypes were determined based on phylogenetic analysis of nucleotide sequence of genome fragment coding capsid protein.

RESULTS

During examination of 5759 children with AEI from July 2006 to June 2011 astroviruses were detected in 2.6% of cases, and in 2010 - 2011 the frequency of astrovirus detection (5.19%) was significantly higher than in the previous epidemic seasons and the average based on the whole observation period. Genotyping of the detected astroviruses showed that genotype 1, 2, 3, 4, 5 astroviruses circulated on the territory of Nizhny Novgorod with predomination ofgenotype 1. Genotype 1 astroviruses are presented by genetic lineages 1a, 1b, 1d with predomination of lineage la. From the start of 2010 all the detected isolates from genetic lineage la belonged to a single new sublineage - 1a-2010. The second by quantity of detected isolates were genotype 5 astroviruses identified for the first time in Nizhny Novgorod in July 2010. Genotype 2, 3 and 4 astroviruses were detected in isolated cases.

CONCLUSION

Activation of astrovirus circulation in the population of Nizhny Novgorod that was shown by a significant increase of frequency of their detection in children with AEI in 2010 - 2011 epidemic season with the highest probability was caused by appearance of genotype 5 astroviruses, that had not previously been detected in this territory and other territories of Russian Federation.