Low Diversity of Alkhurma Hemorrhagic Fever Virus, Saudi Arabia, 1994–1999

摘要

Alkhurma hemorrhagic fever virus (genus Flavivirus,AHFV) was recently identified as the agent of a viral hem-orrhagic fever in Saudi Arabia and characterized serologi-cally and genetically as a variant genotype of KyasanurForest disease virus (KFDV). Since viral diagnosis and vac-cine development may be hindered by genetic diversity,this study was intended to address AHFV genetic hetero-geneity. Eleven strains isolated from hospitalized patientsfrom 1994 to 1999 in Saudi Arabia were sequenced in theenvelope, NS3, and NS5 genes. Homologous sequenceswere compared and used to look for patterns reflecting spe-cific evolution associated with spatiality, temporality, infec-tion pathway, and disease prognosis. Genetic analysesshowed low diversity, which suggests a slow microevolu-tion. Evaluation of divergence times showed that AHFV andKFDV ancestral lineage diverged 66–177 years ago, andthe diversity observed within the studied AHFV strainsreflected a 4- to 72-year period of evolution