Phylogenetic and serological characterization of echovirus 11 and echovirus 19 strains causing uveitis.

The strains of echovirus 19 (EV 19) and echovirus 11 (EV11), isolated from infants with similar clinical symptoms of acute enterovirus uveitis (EU) in Russia (Siberia) in 1980-1989, were investigated phylogenetically (nucleotide sequence of a 300 nt fragment in 5' NTR and VP4 junction) and serologically. The result confirmed that viruses belong to the Enterovirus genus, with 58-80% nt sequence homology with previously sequenced enteroviruses, and showed the genetical identity between the strains isolated during each of five outbreaks of the EU. The results also demonstrated that isolates from the last three outbreaks of EU belong to the same phylogenetic group despite the remarkable spatial and temporal distance between the outbreaks. The results confirm the role of these echoviruses in the etiology of the EU. Based on phylogenetic and serological comparisons the studied strains were divided into three distinct groups: group I, EV19/K (Krasnoyarsk, 1980-1981), group II, EV11/A (Krasnoyarsk, 1982), group III, EV11/B (Krasnoyarsk, 1986; Omsk, 1987-1988; Irkutsk, 1989). Minor details of the epidemiology of the outbreaks were also revealed.