Difference in antibody reactivity between complement fixation and immune adherence hemagglutination tests with virus antigens

Abstract

Complement-fixing (CF) IgM antibody to infantile gastroenteritis virus (a rotavirus) did not show the reactivity of immune adherence hemagglutination (IAHA). Early IgG CF antibody produced in patients and in guinea pigs experimentally infected with Japanese encephalitis virus (a flavivirus) had weak reactivity in IAHA tests. Late antibody showed higher titers by IAHA than by CF. Early antibodies with lower affinity may be inefficient in the IAHA reaction. A low ratio of IAHA/CF antibody titers in a serum may suggest a recent rotavirus infection. The IAHA reaction is evidently more type specific than the CF reaction for identifying the serotype of antigenically cross-reacting viruses with hyperimmune sera.