Isolations of Cache Valley virus in Texas, 1981.

Area of Science:

• Virology
• Arthropod-borne viruses
• Bunyaviridae family

Background:

• Bunyamwera serogroup viruses are significant arboviruses.
• Cache Valley virus is a notable member of this serogroup.

Purpose of the Study:

• To characterize two novel Bunyamwera serogroup virus isolates.
• To determine the relationship of these isolates to known viruses.
• To assess the pathogenicity of these isolates in animal models.

Main Methods:

• Virus isolation from cattle and sheep.
• Complement-fixation and neutralization tests for serogroup identification and relationship determination.
• Physicochemical characterization (lipid solvent, heat, pH sensitivity).
• In vitro cell culture studies (cytopathic effects, plaque formation).
• In vivo pathogenicity studies in mice and experimental infection of sheep and goats.

Main Results:

• Two virus isolates (AR 168 and 7856) were identified as Bunyamwera serogroup members.
• Isolates showed close relation to Cache Valley virus.
• Characterization revealed typical Bunyavirus properties (lipid-sensitive, size, heat/pH labile).
• Pathogenicity was observed in suckling mice (intracranial) and experimentally infected sheep/goats, causing central nervous system disturbances.

Conclusions:

• The characterized isolates represent a Bunyamwera serogroup virus closely related to Cache Valley virus.
• Experimental infection demonstrated neurotropic potential in ruminants.
• These findings contribute to understanding Bunyamwera virus diversity and pathogenicity.