Tuberculosis Health Article

TUBERCULOSIS

Tuberculosis (TB), an infectious disease, has been present throughout ancient and modern history. TB rates in the United States are on the decline after a resurgence from 1985 to 1992. However, TB continues to be a major killer in much of the world. The implications of this epidemic are global, as travel and migration are now part of everyday life.

Although the cause, diagnosis, and treatment and prevention of TB are known, paradoxically, the disease continues to increase as a public health challenge. Caused by a bacterium called Mycobacterium tuberculosis, TB spreads via an airborne route from an infectious person coughing, sneezing, laughing, or singing. The bacteria infect mainly other individuals who have frequent and prolonged contact with a contagious TB case.

HISTORY

TB's existence dates back many centuries. There are references to TB in third-century B.C.E. Chinese and second-century B.C.E. Indian texts; Plato and Hippocrates wrote about it around 400 B.C.E. TB was commonly known as consumption in Europe, a cause of death for hundreds of thousands in the late eighteenth and nineteenth centuries. This is when TB in close groups was first observed and assumed to have a genetic cause, since it was commonly seen in families.

In 1882 Robert Koch's discovery of Mycobacterium tuberculosis led to the recognition of TB as an infectious disease. This discovery also led to interventions for interrupting transmission from person-to-person.

Beginning in the late 1880s, TB patients were treated in sanitoria with various modalities, including exposure to fresh air, exercise, and nourishment. About 50 percent of patients recovered or had long-term remission. However, as is known today, their "cure" was not due to the treatments administered but perhaps to self-healing mechanisms.

In the early twentieth century, public health interventions became key in controlling the spread of TB in the cities, where TB was most prevalent. For example, Herman M. Biggs, General Medical Officer of New York City, actively catalogued lists of TB patients and enforced isolation and environmental mechanisms to control TB, including the opening of a TB hospital to quarantine patients. Between 1914 and 1923, the Metropolitan Life Insurance Company conducted the "Framingham Tuberculosis Project" using community nurses to visit the homes of its clients to do assessments, teach health practices, and collect data for research and policy-making purposes. The project was in response to a high rate of TB-related mortality among Metropolitan customers. As a result, mortality rates for TB in the Metropolitan pool declined by 68 percent.

Beginning in 1921, the Bacille Calmette Guerin (BCG) vaccine was used to prevent TB. Still used in many parts of the world but not in the United States, the vaccine is not effective, except perhaps in infants. The discovery of streptomycin in 1943 brought drug treatment for TB. Between 1943 and 1952, two more TB drugs, para-amino-salicylic acid (PAS) and isoniazid (INH), were discovered. Sanitoria began to close in the early 1970s, as TB could be now be treated on an outpatient basis, as evidenced by success in the decrease in TB rates with combined drug treatment and infection-control mechanisms.