Why medicines don't work for some has caught the attention of scientists across the world. It is attributed to a variety of factors, ranging from genetic changes to antibiotic resistance. India, one of the largest consumers of antibiotics in the world, has a high prevalence of drug-resistant organisms. “Multi-drug resistant tuberculosis, an emerging health crisis, requires urgent attention,” says Dr. Swati Rajagopal, consultant, infectious diseases and travel medicine at Aster CMI Hospital, Bengaluru.