document: Tuberculosis has become the world 's deadliest infectious disease , and the toll could soon rise even more dramatically if controls are not initiated quickly , the World Health Organization said Monday . The U.N. agency , in its first comprehensive look at global tuberculosis in a decade , said the disease kills nearly 3 million people a year , most of them between the ages of 15 and 59 , `` the segment of the population that is economically most productive . '' WHO attributed the sharp rise in part to the growing AIDS epidemic . It estimated that about 3 million people worldwide are dually infected with the human immunodeficiency virus -LRB- HIV -RRB- , which causes AIDS , and tuberculosis . `` It is becoming a parallel epidemic , and it is this trend that has public health officials worried , '' Dr. Hiroshi Nakajima , director general of WHO , said in a statement . The agency estimated that between 15 million and 20 million adults will be infected with HIV by the year 2000 , and it predicted that the number of cases and deaths from tuberculosis will rise sharply as a result , especially in sub-Saharan Africa , Latin America and Southeast Asia . `` These new data have been stunning to everyone , because an awful lot of people had thought that tuberculosis had gone away , '' said Dr. Barry Bloom , a professor of microbiology at the Albert Einstein College of Medicine in New York and a consultant to the United Nations . Tuberculosis is a highly communicable disease of the lungs and other organs caused by a bacterium transmitted through the air when infected people cough or sneeze . There are about 8 million new cases of tuberculosis a year , according to the U.N. agency . About half of these are infectious . Also , an estimated 1.7 billion individuals worldwide carry the organism but are not infectious to others . In these individuals , the organism can remain dormant without causing active disease for many years unless the immune system is somehow impaired . AIDS , or acquired immune deficiency syndrome , destroys the body 's immune system . An individual does not have to have a damaged immune system to contract an active case of tuberculosis . But when a case of tuberculosis becomes active , as it can in individuals who carry the organism , that person can also infect numerous others . This is what is happening in developing nations , where the AIDS epidemic is raging . `` In many places , more than half the beds in medical wards are patients with tuberculosis , '' Bloom said . `` Many of these people do , in fact , die of AIDS . But if they 're not treated for tuberculosis , those people will be spreading the disease -LRB- tuberculosis -RRB- in their communities . You do n't have to have a depressed immune system to get tuberculosis . '' In the United States , public health officials began to recognize about five years ago that tuberculosis -- after steadily declining since the 1950s -- was making a surprising comeback as a result of the AIDS epidemic . At that time , they noticed a startling and unexpected drop in the rate of decline of tuberculosis cases . This year , Bloom said , the number of cases of active tuberculosis in the United States is up nearly 5 % over last year , with 23,495 new cases . The overall incidence of tuberculosis in the United States is 9.5 cases per 100,000 population , he said . In New York City , which has the highest number of AIDS cases in the nation , the incidence is 36 per 100,000 , Bloom said . Effective drugs to combat tuberculosis cost about $ 30 to $ 50 per person , given over six months . However , the drugs are not always available in developing countries , and compliance is a major problem . The drugs must be taken for the entire six months to eliminate the infection .
extractive_keyphrases: deadliest infectious disease world health organization global tuberculosis tuberculosis cases aids epidemic human immunodeficiency virus parallel epidemic