Abstract:Introduction: Despite the effective pre-and post-exposure treatments, at least 60,000 deaths from rabies occur worldwide every year. Post-exposure treatment is considered as one of the most significant measures for preventing human deaths in exposed individuals. The 2-1-1 rabies post-exposure treatment schedule known as Zagreb regimen is an abbreviated immunization plan in which a tissue culture rabies vaccine is administered intramuscularly at two sites on day 0 and at one site on days 7 and 21. Objectives: In this study the efficacy of rabies vaccine administration under Zagreb regimen in an Iranian group of patients attending Pasteur Institute of Iran was evaluated. Methods: Rabies neutralizing antibody titer was measured in 75 serum samples collected from 25 volunteers receiving post exposure treatment by rapid fluorescent focus inhibition test (RFFIT), and ELISA. Results: All patients were negative for rabies antibody in both ELISA and FRRIT tests on day 0. A satisfactory rabies virus antibody response with the titer of ≥0.5 IU/ml was detected in all patients on day 21 and two weeks after the completion of vaccination (day 35). Conclusions: Rabies immunization with rabies Vero-cell vaccine (PVRV) under the 2-1-1 schedule (Zagreb regimen) could result in an adequate immune response without any adverse effect. However a more comprehensive comparative study is underway to confirm these findings.