when a 16-year-old boy was treated for bubonic plague in Madagascar two years ago, the scientific community was unaware of what was in store. Some French researchers have recently published their findings in the New England Journal of Medicine . They say the strain of Yersinia pestis , the bacterium that causes bubonic plague, in the above mentioned case had acquired resistance to a wide range of antibiotics that are commonly administered to treat the disease. The boy survived after one of the three antibiotics prescribed to him worked.
Researchers point out that the strain isolated from the boy has acquired a set of five antibiotic resistance genes at the same time from some other bacterium species. Such transfers of genes are responsible for the spread of drug resistance to other diseases but this is the first time this has happened in the case of a patient suffering from plague. How rare or common is this bacterium is not known. Though the report has no immediate consequences on public health, health experts point out that the incident highlights the growing problem of drug resistance in several diseases.
"Right now, it is just an isolated case," says David Dennis, epidemiologist and plague specialist at the Centers for Disease Control and Prevention, Atlanta, usa . "It is quite interesting. It also serves as a warning that we need to be aware of the emergence of antibiotic resistance diseases, and have the capabilities to detect, characterise, and contain them." Stuart Levy, head of the Center for Adaptation Genetics and Drug Resistance at Tufts University's medical school, Boston, says: "We know that this agent exists, and have to be alert for it in other countries where we know that antibiotic resistance has emerged in so many bacteria."
Plague is transmitted to human beings by the bite of fleas that infest rodents carrying the disease. It is characterised by the formation of tender and swollen lymph nodes known as buboes, hence the name bubonic plague. Sometimes, the disease is transmitted from person to person through microscopic droplets made airborne due to coughing. In such cases, it is called pneumonic plague. In the 14th Century, an epidemic of bubonic and pneumonic plague ravaged through Europe reducing the population by one-third, as described by the French chronicler Jean Froissart. About 25 million people died -- more than the toll of any other epidemic or war up to that time.
Such memories of the disease have caused alarm following the detection of the drug resistant strain in Madagascar. But in recent times, plague has ceased to be the menace it once was. About 2,000 cases of the disease are detected every year, most of them in India and east Africa. If given in time, antibiotic treatment can curtail the death rate to 15 per cent from about 60 per cent. In the us , five cases were reported last year, two of which were fatal. Dennis says that of all the cases reported in the us , none was drug resistant.