Abstract
Despite the introduction of mass immunization, diphtheria continues to play a major role as a potentially lethal infectious disease in many countries. Delay in the specific therapy of diphtheria may result in death and, therefore, accurate diagnosis of diphtheria is imperative. This study was carried out at National Centre for Disease Control (NCDC), Delhi, India, on samples of suspected diphtheria cases referred from various government hospitals of Delhi and neighbouring areas during 2012-2014. Primary identification of Corynebacterium diphtheriae was done by standard culture, staining and biochemical tests followed by toxigenicity testing by Elek's test on samples positive for C. diphtheriae. The results showed persistence of toxigenic C. diphtheriae in our community indicating the possibility of inadequate immunization coverage.