Genome Research:
Akabane Virus

Akashi H; Kaku Y; Kong XG; Pang H.
     Sequence determination and phylogenetic analysis of the Akabane bunyavirus
     S RNA genome segment.
   Journal of General Virology, 1997 Nov, 78 ( Pt 11):2847-51.

Abstract: The nucleotide sequence of the small (S) RNA segment of Akabane (AKA)
    bunyavirus was determined. The segment is 858 nucleotides long and contains
    two overlapping open reading frames (ORFs), which encode the nucleocapsid
    (N) and nonstructural (NSs) proteins, consistent with other bunyaviruses.
    Comparisons with the Aino virus S RNA sequence indicated that there is
    73.5% identity in nucleotide sequence. However, the sequence identity of
    the 5' non-coding region of the genomic RNA between these two viruses is
    only 55%. The N ORFs from 20 Japanese and 2 Australian isolates of AKA
    virus were sequenced and subjected to phylogenetic analysis. This suggested
    that AKA virus has evolved in multiple lineages. Twenty-three isolates were
    grouped into three major clusters, and the cluster which includes recent
    isolates was subdivided into two branches. Thus, phylogenetic analysis of
    the AKA virus N protein gene gives a greater insight into bunyavirus

La Crosse Virus

 Huang C; Thompson WH; Karabatsos N; Grady L; Campbell WP.
     Evidence that fatal human infections with La Crosse virus may be
     associated with a narrow range of genotypes.
   Virus Research, 1997 May, 48(2):143-8.

Abstract: La Crosse (LAC) virus belongs to the California (CAL) serogroup of
    the genus Bunyavirus, family Bunyaviridae. It is considered one of the most
    important mosquito-borne pathogens in North America, especially in the
    upper Mid-West, where it is associated with encephalitis during the time of
    year when mosquitoes are active. Infections occur most frequently in
    children and young adults and, while most cases are resolved after a period
    of intense illness, a small fraction (< 1%) are fatal. At present there
    have only been three isolates of LAC virus from humans all made from brain
    tissue postmortem. The cases yielding viruses are separated chronologically
    by 33 years and geographically from Minnesota/Wisconsin (1960, 1978)
    to Missouri (1993). The M RNA sequence of the first two isolates was
    previously reported. The present study extends the observations to the
    isolate from the 1993 case and includes several mosquito isolates as well.
    A comparison of the M RNAs of these viruses shows that for the human
    isolates both nucleotide sequence and the deduced amino-acid sequence of
    the encoded proteins are highly conserved, showing a maximum variation of
    only 0.91% and 0.69%, respectively. This high degree of conservation over
    time and space leads to the hypothesis that human infections with this
    particular genotype of LAC virus are those most likely to have a fatal
    outcome. It is also shown that a virus with this genotype could be found
    circulating in mosquitoes in an area more or less intermediate between the
    locations of the first and second fatal cases.

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