title: Comparison of virulence between two strains of Rattus serotype hemorrhagic fever with renal syndrome (HFRS) virus in newborn rats.
abstract: Two strains of hemorrhagic fever with renal syndrome (HFRS) virus from Rattus, SR-11 and KI-262, showed virtually identical antigenicity but differed from prototype strain Hantaan 76-118 (Apodemus origin) in a neutralization test. Wistar newborn rats inoculated intraperitoneally (i.p.) with SR-11, which was isolated from a laboratory rat associated with an outbreak of HFRS, developed clinical signs such as ataxia and limb paralysis and died at about 18 days after inoculation. The LD50 of SR-11 in 1-day-old rats was 10(1.2) focus-forming units (FFU). In contrast, the animals inoculated i.p. or intracerebrally with 10(4) FFU of KI-262, which was from a wild rat in a dumping-ground area--an enzootic focus where no human cases have been recorded--did not show any significant clinical signs. The susceptibility of rats to SR-11 fatal infection was age-dependent. Virus titers in brains, lungs, kidneys, and livers of the rats inoculated with SR-11 were significantly higher than those in the same organs of the animals infected with KI-262. Necrosis of neurons in the brain tissue occurred in the rats infected with SR-11, while it was mild in the animals infected with KI-262.
authors.affiliation: Department of Veterinary Public Health, Faculty of Veterinary Medicine, Hokkaido University.
authors.forename: X K
authors.initials: XK
authors.lastname: Zhang
authors.forename: I
authors.initials: I
authors.lastname: Takashima
authors.forename: F
authors.initials: F
authors.lastname: Mori
authors.forename: N
authors.initials: N
authors.lastname: Hashimoto
mesh_terms: D000375:Aging / Q000276:immunology; D000818:Animals; D000831:Animals, Newborn; D000914:Antibodies, Viral / Q000032:analysis / Q000276:immunology; D000956:Antigens, Viral / Q000276:immunology; D001921:Brain / Q000473:pathology; D004198:Disease Susceptibility; D005260:Female; D005455:Fluorescent Antibody Technique; D006476:Orthohantavirus / Q000145:classification / Q000302:isolation & purification / Q000472:pathogenicity*; D006480:Hemorrhagic Fever with Renal Syndrome / Q000276:immunology / Q000382:microbiology* / Q000401:mortality / Q000473:pathology; D007074:Immunoglobulin G / Q000276:immunology; D009115:Muridae / Q000382:microbiology; D009500:Neutralization Tests; D009928:Organ Specificity; D011247:Pregnancy; D051381:Rats; D011919:Rats, Inbred Strains; D012703:Serotyping; D013045:Species Specificity; D013047:Specific Pathogen-Free Organisms; D014774:Virulence
chemical_list: D000914:Antibodies, Viral; D000956:Antigens, Viral; D007074:Immunoglobulin G