RESUMO
The pathogenesis of neurologic complications of Lassa fever is poorly understood. A Nigerian patient had fever, disorientation, seizures, and blood-brain barrier dysfunction, and Lassa virus was found in cerebrospinal fluid (CSF) but not in serum. The concentration of Lassa virus RNA in CSF corresponded to 1 x 10(3) pfu/mL, as determined by a quantitative real-time polymerase chain reaction assay. To characterize the Lassa virus in CSF, the 3.5-kb S RNA was sequenced. In the S RNA coding sequences, the CSF strain differed between 20% and 24.6% from all known prototype strains. These data suggest that Lassa virus or specific Lassa virus strains can persist in the central nervous system and thus contribute to neuropathogenesis. Lassa virus infection should be considered in West African patients or in travelers returning from this area who present only with fever and neurologic signs.
Assuntos
Confusão/etiologia , Febre Lassa/líquido cefalorraquidiano , Febre Lassa/complicações , Vírus Lassa/genética , Vírus Lassa/isolamento & purificação , Convulsões/etiologia , Sequência de Aminoácidos , Confusão/líquido cefalorraquidiano , Confusão/virologia , Febre/etiologia , Humanos , Febre Lassa/sangue , Vírus Lassa/classificação , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Nigéria , Filogenia , Reação em Cadeia da Polimerase/métodos , RNA Viral/química , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Convulsões/líquido cefalorraquidiano , Convulsões/virologia , Alinhamento de Sequência , Homologia de Sequência de AminoácidosRESUMO
We describe the isolation and characterization of a new Lassa virus strain imported into Germany by a traveler who had visited Ghana, Côte D'Ivoire, and Burkina Faso. This strain, designated "AV," originated from a region in West Africa where Lassa fever has not been reported. Viral S RNA isolated from the patient's serum was amplified and sequenced. A long-range reverse transcription polymerase chain reaction allowed amplification of the full-length (3.4 kb) S RNA. The coding sequences of strain AV differed from those of all known Lassa prototype strains (Josiah, Nigeria, and LP) by approximately 20%, mainly at third codon positions. Phylogenetically, strain AV appears to be most closely related to strain Josiah from Sierra Leone. Lassa viruses comprise a group of genetically highly diverse strains, which has implications for vaccine development. The new method for full-length S RNA amplification may facilitate identification and molecular analysis of new arenaviruses or arenavirus strains.
