A Randomized Trial for Evaluating Prophylactic Effect of Intradermal and Intramuscular Hepatitis B Vaccine

Background: Hepatitis B virus is one of the most common causes of chronic liver diseases. Vaccination is the best way of prophylaxis and is of utmost importance. This study was conducted to compare the prophy-lactic effect of intradermal and intramuscular injection of hepatitis B vaccine. Methods: A blind randomized clinical trial was performed among subjects who presented to the infectious diseases clinics to receive HB vaccine in Mashhad, north east Iran, during 2002- 2004. Eighty men and women who were HBs Ag & HBs Ab negative were randomly received 0.1 ml intradermal (study group) or 1ml intramuscular (control group) vaccine. The vaccine was injected into the deltoid region at months 0, 1, and 6. One month later, the HBsAb level was checked. The levels less than 10IU/L, 10-100 IU/L and more than 100 IU/L were defined as negative, mild positive and strong positive responses, respectively. Results: Intramuscular and Intradermal injections resulted in 95%, 87.5% strong positive, 2.5%, 7.5% mild positive and 2.5%, 5% negative responses respectively. Mann-whitney and Fisher’s Exact Test showed the difference between results was not statistically significant (P > 0.05). Conclusion: Due to small difference in the effectiveness of these two methods and the cost effectiveness of intradermal injection, this route could be substituted for intramuscular injection.