Resurgence of Diphtheria in Rural Areas of North Karnataka,India

Background: A diphtheria outbreak was identified from Vijayapura (formerly Bijapur) district in the South Indian state of Karnataka in 2011. There was a surge in the number of throat swab samples received under the Integrated Disease Surveillance Programme (IDSP) in North Karnataka since then. Objectives: A microbiological study was undertaken to generate information on the status of resurgence of the disease in the region. Materials and Methods: Throat swabs from 432 suspected cases of diphtheria during 2012–2015 were obtained from government hospitals and primary health centres of 8 districts in North Karnataka and were processed for the culture and identification of Corynebacterium diphtheriae. Polymerase chain reaction for the presence of toxin gene (toxA and toxB) was carried out on the isolates. Antibiotic sensitivity tests were performed on the isolates with a panel of 14 antibiotics. Results: Thirty-eight (8.79%) out of 432 samples yielded C. diphtheriae on culture. All isolates possessed the diphtheria toxin gene. Out of the 38 confirmed cases, whereas 21 (55.26%) were between 1 and 5 years of age, 14 (36.84%) were aged between 5 and 10 years. Male children were three times more than females in confirmed cases. No information was available on the immunisation status of the cases. Emergence of resistance to penicillin was found with minimum inhibitory concentration reaching up to 6.00 μg/ml. Conclusion and Discussion: Our study identified an upsurge in cases of diphtheria in North Karnataka, particularly in Vijayapura District, and to the best of our knowledge, reports the emergence of penicillin resistance for the first time in India. The study calls for enhanced surveillance for the disease, making antidiphtheritic serum available in key hospitals in the region and serves to provide a baseline for future assessment of the impact of the recently launched ‘Mission Indradhanush’ programme in strengthening Universal Immunisation Programme (UIP).