Aseptic meningitis in Germany associated with echovirus type 13

Background: Echoviruses are the commonest cause of aseptic meningitis. Echovirus type 13 which has no been isolated in Germany over a long period of time was the predominant enterovirus serotype associated with different local outbreaks of aseptic meningitis in Germany in 2000. Methods: Virus isolation was performed from cerebrospinal fluid and stools. In order to study he genetic relationship of echovirus type 13 isolates, sequence analysis of a part of VPI ( similar to 300 nt) was carried out. Isolates from different geographic regions were compared to each other as well as to elder viruses (prototype strain from 1953, four isolates from 1965-1986). Results: Overall, 55 isolates of echovirus type 13 were obtained from different parts of Germany. It was shown that the new isolated strains have a very high degree of homology on the nucleotide level (> 98%)) but differ significantly from the old strains (76-85%). Conclusions: a) Rare enterovirus sero types can cause serious illness. b) The molecular drift has also been shown for other enterovirus serotypes.