Partial genomic sequence determination of yellow fever virus strain associated with a recent epidemic in Gabon.

A limited epidemic, with important mortality among the initial human cases, occured in a forest region in the north of Gabon by the end of 1994. It was identified as yellow fever according to first serological and reverse transcription/polymerase chain reaction (RT-PCR) results, but no virus was isolated. We received 37 sera from people who lived in the same region and presented symptoms of the disease during the period of concern. In ten of them, we were able to detect and identify yellow fever virus (YFV) RNA by RT-PCR and endonuclease digestion of the RT-PCR products. Nucleotide (nt) sequence of two regions (242 and 161 nt long) of YFV RNA was determined for three sera. As it differed from that of the Asibi strain of YFV, the presence of a new topotype (strain) of YFV is presumed.