Ten year longitudinal study of efficacy and safety of purified chick embryo cell vaccine for pre- and post-exposure prophylaxis of rabies in Indian population.

One thousand three hundred and seventy-five (1375) persons, who were vaccinated against Rabies with Purified Chick Embryo Cell (PCEC) vaccine from 1984 to 1993, were included in this ten-year longitudinal study, conducted to observe the consistency, immunogenicity, inocuity, safety and efficacy of PCEC vaccine under controlled trial and field conditions. The study period was divided into three phases. Phases I and II covered the premarketing controlled trial and Phase III the post-marketing serosurveillance study of the vaccine. During Phase I, fifteen healthy volunteers were given a pre-exposure regime of vaccine on Day 0, 7 and 21, and the rest 15, simulated post-exposure regime on Day 0, 3, 7, 14, 30 and 90. All the subjects had satisfactory antirabies antibody response with mean titres, of 7.08 and 5.72 I.U./ml respectively, and minimal side reactions. In the Phase II, from 1984-85, 56 persons with proven rabid animal bites were given post-exposure vaccination and all had satisfactory antibody titres with mean titre of 4.45 I.U./ml after 6th dose of vaccine and with minimal side reactions. 19 to 36 months follow up after vaccination revealed no vaccine failures. In the Phase III post-marketing field study conducted from 1985 to 1993, 1289 persons reported to our Centre for consulation and antirabies antibody titre estimation following PCEC vaccination. One thousand two hundred and fifty-two (1252) persons took post-exposure vaccination following bites by rabid animals, contact with an hydrophobia patient and 37 high risk personnel took pre-exposure vaccination.(ABSTRACT TRUNCATED AT 250 WORDS)