What is Tuberculosis
Tuberculosis or TB is an infectious, communicable disease that usually affects the lungs, but can also affect any other part of the body. Robert Koch, a German physician discovered the tuberculosis bacteria (mycobacterium tuberculosis) in 1882. This discovery won him the Nobel prize. In the past, people referred to this disease as "consumption" because those with untreated tuberculosis experienced extreme weight loss.
Tuberculosis is spread when people who have the active disease cough, sneeze, or spit. Once the bacteria is airborne, it is inhaled by those around and it settles in the lungs. From there, it can spread throughout the body.
Many of the tuberculosis infections are "latent" - that is, the patient experiences no symptoms. Approximately one-tenth of those with latent tuberculosis will go on to develop full-blown tuberculosis, which will kill about half of those who do not receive medical attention.
According to the Communicable Disease Management Protocol of the Province of Manitoba, Canada, "more than 90% of cases are symptomatic at the time of primary infection and can be identified...through...the tuberculin skin test...." Many of the patients examined had clear chest X-rays, although fibrotic lesions were visible in some.
"In the past, primary infection occurred almost entirely in childhood, but as the incidence of tuberculosis has declined, primary tuberculosis [that is, first time infections] is also being seen in adults." (www.gov.mb.ca)
It is estimated that over 8 million new cases of tuberculosis happen each year worldwide and about 2 million of those die. In the last 10 years, TB cases have increased by about 20% in Africa, Asia and Latin America. If these trends continue, 36 million deaths will have occurred from TB by the year 2020 - 10 years from now.
About 10-15 million Americans are currently infected with the TB bacteria with 22,000 new cases occurring each year. Tuberculosis is rare in Canada, with approximately 70% of Canadian TB cases originating from exposure outside the country.