ABSTRACT
AIM: Analysis of manifestation of epidemic process of aseptic meningitis and causes of its activation using molecular genetic methods. MATERIALS AND METHODS: Samples of feces and CSF, nasopharyngeal swabs from 296 patients with aseptic meningitis (AM), as well as 240 samples of drinking water and 6 samples of lake water were studied. Epidemiologic analysis, isolation of enteroviruses in Hep-2 and RD cell cultures, RT-PCR, partial sequencing of 5'NTR and genome region coding VP1 were performed. RESULTS: Marked rise of AM caused by enteroviruses in Nizhny Novgorod during 2001 - 2007 was demonstrated. From August to October 2007, enteroviruses were detected in 93.8% of patients with AM (22.5 per thousand). Seasonal rise of incidence was determined by 9 serotypes of enteroviruses: E30 - 26 cases (53.1%), E7 - 7 (14.3%), E18 - 5 (10.3%), E13 - 3 (6.1%), E9 - 2 (4.0%), CB5 - 3 (6.1%),CA1 - 1 (2.0%), CA9 - 1 (2.0%), CA13 - 1 (2.0%). Serotype E30, represented by two subtypes, dominated. Dominating subtype E30-N1 was closely related with E30 strains isolated in 1994 - 2001 in Europe. Subtype E30-N2 was genetically related with Asian strains isolated in 2000 - 2006. RNA of E7, E9, E13, E18, CB5 viruses and dominating subtype E30-N1 were detected in nasopharyngeal swabs from patients with AM, which can explain rapid and wide spread of these viruses in susceptible population by aspiration route of transmission. CONCLUSION: Increased incidence of AM in Nizhny Novgorod in 2007 was caused by variant of E30 virus, which was genetically related with strains isolated in European countries in 1997.
