Antibody responses induced by immunization with a Japanese rabies vaccine determined by neutralization test and enzyme-linked immunosorbent assay.

ABSTRACT

The immunogenicity of a Japanese purified chick embryo cell culture rabies vaccine (PCECV) was examined. Serum samples were obtained from 86 subjects after pre-exposure or post-exposure prophylaxis. Rabies antibody titres were determined by neutralization test and enzyme-linked immunosorbent assay (ELISA). Titres higher than 0.5 international units (IU)/ml were demonstrated by neutralization test in all the 19 subjects after three-time pre-exposure immunization on days 0, 30 and 180. Titres higher than 0.5IU/ml were also demonstrated by neutralization test in all the 23 subjects after four-time post-exposure immunization on days 0, 3, 7 and 14. There was a correlation between neutralization and ELISA antibody titres (r=0.697); however, neutralization titers were higher than ELISA titres for most of the samples. The results suggest that current Japanese rabies vaccine induces recommended levels of neutralizing antibodies after pre- and post-exposure prophylaxes.