Revision of the Thai Red Cross intradermal rabies post-exposure regimen by eliminating the 90-day booster injection.

The Thai Red Cross intradermal post-exposure rabies prophylaxis regimen (TRC-ID) is being used in Thailand, the Philippines, Sri Lanka and is making inroads in India. It consists of two injections of 0.1 mL of any World Health Organization recommended tissue culture rabies vaccine intradermally at two sites on days 0, 3, 7, followed by one injection on days 28 and 90. Two decades of experience had shown that approximately 11% of 187,000 possibly rabies exposed subjects who received the TRC-ID schedule, did not return for the 90-day booster. No rabies deaths had, however, been reported from this group. This stimulated two studies to determine whether the 90-day booster can be abolished. They demonstrated that, if the single 28-day 0.1 mL injection is increased to two at two sites, a comparable antibody response can be achieved and the 90-day booster can be omitted. The tissue culture rabies vaccine used in the preliminary study was purified chick embryo vaccine (PCEC Chiron) and for this study it was chromatography purified Vero cell vaccine (CPRV, Aventis-Pasteur). CPRV had been previously shown to be as immunogenic and effective as purified Vero cell rabies vaccine (PVRV).

Common dilemmas in managing rabies exposed subjects.

Health care staff managing rabies exposures in a canine endemic or epidemic environments are often faced with having to make treatment decisions where there are no firm guidelines from WHO or local public health authorities. We have made an attempt to identify several common events that presented to a busy animal bite clinic in a rabies endemic country. Leading experts in this field have been queried about their management opinions in such situtions. They have revealed little uniformity. It appears that there is still much controversy and lack of evidence-based approach from international authorities, and that more research and data collection is needed to resolve some of these issues and provide better guidelines in this field.