Intra-dermal administration of rabies vaccines in developing countries: at an affordable cost.

Rabies is a virtually 100% fatal acute viral encephalitis. Rabies occurs in more than 150 countries and territories. Globally there are 17.4 million animal bite cases and more than 55,000 deaths annually. India's 20,000 deaths accounts for 36% of global and 65% of the Asian (31,000) deaths. The Intradermal Rabies Vaccine (IDRV) was first started in Thailand in 1984. In 1992, World Health Organization approved it for use in developing countries which face a shortage of rabies vaccine due to paucity of funds. Vaccines like Purified Vero cell vaccine (PVRV), Purified chick embryo cell vaccine (PCECV) and Human diploid cell vaccine (HDCV) that can be injected by the intradermal route for Post Exposure Prophylaxis as approved by WHO. The regimen approved by the WHO/DCGI India is the Updated Thai Red Cross Regimen, which involves injection of 0.1 mL of reconstituted vaccine per ID site and on two such ID site per visit on Days 0, 3, 7 and 28 (2-2-2-0-2). All reconstituted vaccine unused at the end of 6-8 h must be discarded. The ID route is ideal in terms of economic benefits, safety and efficacy. This reduces the cost of vaccination by about 68%, which is clearly an attractive option for resource-starved countries like India.