Immunogenicity Study of a Reduced (4-dose) Vaccine Schedule and Rabies Immunoglobulins

Immunogenicity Study of a Reduced (4-dose) Vaccine Schedule and Rabies Immunoglobulins for Post-exposure Rabies Treatment

Reduced 4-dose intramuscular rabies vaccination schedule was announced by US-ACIP and WHO to be one of the post-exposure prophylaxis regimens. However, concurrent usage of this regimen with rabies immunoglobulin have never been studied in the aspect that the immunity level would above the protective level required by WHO (0.5 IU/ml) for at least a year period. This study would access this subject.

Controlled trial study All 75 volunteers who had never had rabies immunization would be enrolled and designated into 3 groups. group 1 : 25 Healthy volunteers age 18 - 60 yr who were attacked by mammals, possible exposed to rabies and had WHO category III exposure, all receive standard post - exposure rabies treatment with 5-dose intramuscular rabies vaccine on day 0,3,7,14,28 and 40 IU/kg of equine rabies immune globulin (ERIG). group 2 : 25 Healthy volunteers age 18 - 60 yr receive 4-dose intramuscular rabies vaccine on day 0,3,7,14 and 40 IU/kg of equine rabies immune globulin (ERIG). group 3 : 25 Healthy volunteers age 18 - 60 yr receive 4-dose intramuscular rabies vaccine on day 0,3,7,28 and 40 IU/kg of equine rabies immune globulin (ERIG). 5 cc - Blood would be drawn from all volunteers before vaccination and on day 14, 28, 90 and 360 for rabies neutralizing antibody titers (RNab). The GMTs of RNab among both groups would be analyzed and compared.

Healthy volunteers received rabies vaccination intramuscularly on day 0,3,7 and 28 with equine rabies immunoglobulin 40 IU/Kg on day 0.

Healthy volunteers received rabies vaccination intramuscularly on day 0,3,7 and 14 with equine rabies immunoglobulin 40 IU/Kg on day 0.

Rabies exposed victims receive rabies vaccination intramuscularly on Day 0,3,7,14,28 with equine rabies immunoglobulin 40 IU/Kg on day 0

Group 1: rabies vaccination was given to rabies exposed victims on day 0,3,7,14,28 with ERIG on day 0. Group 2: rabies vaccination was given to healthy volunteers on day 0,3,7,14 with ERIG on day 0. Group 3: rabies vaccination was given to healthy volunteers on day 0,3,7,28 with ERIG on day 0.

Rabies Neutralizing antibody titers in volunteers who receive rabies vaccination on day 0,3,7,14 would be determined on day 0,14, 28, 90 and 360. Rnab titers above 0.5 IU/ml would be considered as protective levels as WHO recommendation.

Rabies Neutralizing antibody titers in volunteers who receive rabies vaccination on day 0,3,7 and 28 would be determined on day 0,14, 28, 90 and 360. Rnab titers above 0.5 IU/ml would be considered as protective levels as WHO recommendation.

Inclusion Criteria: healthy volunteers age 18-60 years. Exclusion Criteria: received prior rabies immunization pregnancy immunocompromised conditions