Potency Titration of Oral Polio Vaccine by Estimation of Live Virus Content Using Tissue Culture Technique

Representative vaccines from 34 different batches of oral log10 (6.425) and a minimum titre of polio vaccine (OPV) were tested for potency by tissue culture technique. All 34 samples were found to be potent, a maximum titre of log10 (6.425) and a minimum titre of log10 (5.86) was obtained. In addition, 6 vaccines from the immunisation clinic (left over sample after immunisation) were also subjected to potency titration and their potency was found to be within normal limits. Adequate potency confirmed ideal storage condition of the vaccines in Armed Forces set up.