Intradermal vaccination for rabies prophylaxis: conceptualization, evolution, present status and future

Abstract

Rabies is a fatal viral encephalitis which can be effectively prevented by prophylactic measures. The currently available cell culture vaccines used for rabies prophylaxis are expensive for use by the standard intramuscular route of administration. In the last 3 decades, intradermal (ID) routes of vaccination using lesser amounts of vaccine as compared to that used for standard intramuscular vaccination have been used extensively in some Asian countries which has reduced the economic burden of rabies prophylaxis and also contributed in achieving a decline in the incidence of human rabies. ID vaccination is based on sound immunological principles and has been found to be safe and immunogenic. New short duration regimens to further economize the cost and enhance patient compliance, and novel non-invasive devices for ID vaccine delivery are being evaluated. Considering the success of ID rabies vaccination in Asian countries, its implementation in rabies endemic African countries should be encouraged.

Keywords::

• immune response
• intradermal vaccination
• rabies
• rabies prophylaxis
• rabies vaccines

Financial & competing interests disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

No writing assistance was utilized in the production of this manuscript.

Key issues

• Rabies is a fatal disease, but preventable with potent vaccines and immunoglobulins.

• Conventional intramuscular (im.) regimens with modern cell culture vaccines are expensive for use in developing countries.

• Intradermal (ID) rabies vaccination with a fraction of im. dose (∼10–20% of im. dose for pre-exposure prophylaxis and 20–40% of im. does for postexposure prophylaxis) is immunogenic and efficacious in preventing rabies.

• In the last 3 decades, millions of people in Asian countries have been benefited by ID rabies vaccination.

• The two-site ID regimen (updated Thai Red Cross regimen) for postexposure prophylaxis is recommended by WHO and is used in several Asian countries including India, Nepal and Bangladesh.

• ID rabies vaccination is more economical for use in large antirabies clinics and hospitals since reconstituted vaccine cannot be stored beyond 6–8 h.

• Use of ID rabies vaccination, which is scientifically rational, highly immunogenic, economical, safe and practically feasible should be encouraged even in developed countries where rabies vaccination is still administered by conventional im. route.

• ID rabies vaccination can also be used for pre-exposure prophylaxis of children in endemic areas and other populations at a high risk of rabies and travelers to endemic countries.

• Newer ID regimens are being evaluated with a view to reduce the duration of treatment and increase patient compliance.

Notes