Laboratory investigation and phylogenetic analysis of enteroviruses involved in an aseptic meningitis outbreak in Greece during the summer of 2007.
BACKGROUND
Aseptic meningitis is the most commonly observed CNS infection and is mainly attributed to Non-Polio Enteroviruses (EV).


OBJECTIVE
Identification and genetic analysis of the EV involved in the recent aseptic meningitis outbreak which occurred in Greece, during the summer of 2007.


METHODS
In total, 213 CSF and faecal samples were examined for EV presence by culture, while enteroviral RNA detection was performed by nucleic acid sequence-based amplification assay (NASBA). EV strains were typed by seroneutralization, as well as nested RT-PCR followed by VP1-2A gene partial sequencing. Phylogenetic analysis was carried out for the identification of the genetic relatedness among the isolated EV strains.


RESULTS
EV detection rate in CSF and faecal samples was 43.9% and 70.8%, respectively. EV serotyping and VP1 region analysis revealed the predominance of echovirus 4 (ECV4) serotype and the circulation of ECV6, 9, 14, 25, Coxsackie A6, A15, A24 and Coxsackie B1 serotypes. All ECV4 isolates presented a 98.7% similarity in nucleotide sequence, with a Spanish ECV4 strain, isolated during a meningitis outbreak in 2006.


CONCLUSIONS
It is the first time that ECV4 is associated with an aseptic meningitis outbreak in Greece, during which 9 different EV serotypes were co-circulating. All Greek ECV4 isolates were closely related to the Spanish ECV4 strain. Genetic analysis of the VP1 gene can significantly contribute to the revelation of the endemic EV strains circulation pattern and their phylogenetic relationship with enteroviruses involved in epidemics of distant geographical areas at different time periods.
Logotheti
Maria
M
National Enterovirus/Poliovirus Reference Laboratory, Hellenic Pasteur Institute, Vas. Sofias 127, 11521, Athens, Greece.
Pogka
Vasiliki
V
Horefti
Elina
E
Papadakos
Konstantinos
K
Giannaki
Maria
M
Pangalis
Anastasia
A
Sgouras
Dionyssios
D
Mentis
Andreas
A
D002648:Child; D002675:Child, Preschool; D004196:Disease Outbreaks; D004770:Enterovirus / Q000145:classification / Q000235:genetics*; D004769:Enterovirus Infections / Q000134:cerebrospinal fluid / Q000453:epidemiology / Q000276:immunology / Q000821:virology*; D005243:Feces / Q000821:virology; D005260:Female; D006115:Greece / Q000453:epidemiology; D006801:Humans; D008297:Male; D008582:Meningitis, Aseptic / Q000134:cerebrospinal fluid / Q000453:epidemiology / Q000276:immunology / Q000821:virology*; D010802:Phylogeny; D012367:RNA, Viral / Q000032:analysis / Q000134:cerebrospinal fluid; D020133:Reverse Transcriptase Polymerase Chain Reaction; D021161:Self-Sustained Sequence Replication / Q000379:methods; D012703:Serotyping
D012367:RNA, Viral