Pathogenicity of Ife virus for Swiss albino mice

Pathogenicity of Ife virus was studied in Swiss albino mice following four inoculation routes. Mice of all ages survived oral infection without seroconversion; subcutaneous (i.c.) and intraperitoneal (i.p.) infections lead to low titre antibody production. Only suckling mice (1-5 days old) succumbed to intracerebral (i.c.) inoculation with infectivity titres which decreased by age and average survival time (AST) increasing with age. Following i.c. inoculation to suckling mice, the brain infectivity titres increased progressively by days post-infection (p.i.). Virus was not recovered from the lungs and kidney but in low titre it was obtained from the liver, spleen, heart and blood at different days p.i. All organs examined showed evidence of complement fixing and immunofluorescent Ife virus antigen. No gross lesions were observed. The histopathological lesions were limited to the brain.