Sixty years ago, the landmark discovery of penicillin as a weapon against bacterial illnesses ushered in a golden era during which scores of infectious diseases could be controlled―if not entirely wiped out. With the increasingly large arsenal of powerful antibiotics developed in subsequent years, pneumonia, typhoid fever, and other illnesses became curable in much of the world where drugs were readily available.    Now, as a result of the overuse, and misuse of these same antibiotics, drug-resistant forms of these and other disease are staging a come back, presenting a global threat to public health. 　Despite medical advances, infectious diseases remain their world's leading cause of death, according to the World Health Organization, which notes, that in the past two decades alone, more than 30 new strains of infectious diseases have appeared. Ironically, hospitals themselves are the most common incubators of many of these drug-resistant germs. 　When harmful bacteria are not completely killed, they undergo genetic mutations, multiply, and come back even stronger. Recently, even vancomycin―considered the most powerful antibiotic available― could not stop the spread of a strong strain of bacteria found in New York City.   Although resistance varies greatly from region to region, studies have shown that some bacterial strains are now up to 55 % to penicillin and up to 30 % resistant to the more powerful methicillin. Drug-resistant varieties of tuberculosis, an infectious coughing disease, have appeared, with up to 40 % of cases showing an ability to survive the initial antibiotic attack.   How has this come about? The causes are several: unnecessary prescription of antibiotics by doctors for viral illnesses or other maladies not caused by bacteria, patients failing to follow dosage instructions or stopping an antibiotics course too soon, and use of antibiotics in feed supplements for livestock whose meat and milk, enter the human food chain. Four common bacteria have now developed resistant forms after having been transmitted from animals to humans.   With the rise of international travel, many of these drug-resistant strains of bacteria are spreading quickly on a global scale. As a result, developed countries are almost as vulnerable as developing countries to the danger of diseases that cannot be stopped. Despite the common threat, however, there has so far been little coordinated effort to monitor the full extent of the problem across borders or to design a systematic campaign to educate doctors, patients, livestock breeders, and others about ways they can help prevent the spread of the these super bugs.   National and international health organizations should help to focus global resources to educate the medical community about the proper use of antibiotics. Some have already begun to lead the way by sharing data and information about the resistance of specific bacterial strains while promoting the development of new antibiotics.