Immunogenicity and feasibility of purified chick embryo cell vaccine.

Two hundred seventy-one children reported at the WHO Collaborative Centre for Rabies Epidemiology for South-East Asia at National Institute of Communicable Diseases, Delhi, for advice and antirabies antibody assessment after post-exposure prophylaxis with purified chick embryo cell (PCEC) antirabies vaccine from January 1986 to October 1992. Vaccine was very well tolerated by these children and only 7% complained about mild to moderate side reactions like pain, induration, fever or rash. On an average, every year 50-55 children had reported at this Centre after post-exposure vaccination with PCEC vaccine excepting years 1986 and 1987. One hundred and forty-four children underwent complete course of post-exposure prophylaxis, i.e., 5 or 6 doses on day 0, 3, 7, 14, 30 and 90 (optional) of PCEC vaccine were administered, forty-three (43) children received 4 doses on day 0, 7, 14 and 30 (day 3 dose was omitted) and eighty-four (84) children received 2 to 3 doses as the biting animals were alive for 10 days in these cases. Two hundred and twenty-nine children (84.5%) were bitten by dogs and in 10%, the dog was proven rabid by laboratory examination of dog brain. One hundred and forty-nine (55%) had Class III bite. Serological response, i.e., antirabies antibody titre in all these children were satisfactory (> 0.5 IU/ml) with mean titre of 1.98 IU/ml irrespective of doses of PCEC vaccine administered. No vaccine failure was observed in this study.