Tuberculosis (TB) Support Group

Tuberculosis is one of the most deadly and common major infectious diseases today. As of 2004, 14.6 million people have active TB disease with nine million new cases of the disease and nearly two million deaths, [1] mostly in developing countries. However, developed countries are not spared the burden of tuberculosis. There is a rising number of people in the developed world who contract tuberculosis because they have compromised immune systems, typically as a result of immunosupressive drugs or HIV/AIDS. These people are at particular risk of tuberculosis infection and active tuberculosis disease.

Most of those infected (90%) have asymptomatic latent TB infection (LTBI). There is a 10% lifetime chance that LTBI will progress to TB disease which, if left untreated, will kill more than 50% of its victims. TB is one of the top four infectious killing diseases in the world: TB kills 1.7 million, and malaria kills 2-3 million.

HIV/AIDS, the neglect of TB control programs, and immigration have caused a resurgence of tuberculosis. Multiple drug resistant strains of TB (MDR-TB) and Extreme Drug-Resistance in Tuberculosis (XDR-TB) are emerging. The World Health Organization declared TB a global health emergency in 1993, and the Stop TB Partnership proposed a Global Plan to Stop Tuberculosis which aims to save an additional 14 million lives between 2006 and 2015.

One-third of the world population (2 billion people) have latent TB infection; in 2004, around 14.6 million people have active TB disease with 9 million new cases. The annual incidence rate varies enormously, from 356 per 100,000 in Africa to 41 per 100,000 in the Americas. In the UK, incidence ranges from 90 per 100,000 in the centre of Birmingham to less than 5 per 100,000 in rural Hertfordshire. Approximately 1.7 million people died from TB in 2004.

TB is spread by aerosol droplets expelled by people with active TB disease of the lungs when they cough, sneeze, speak, or spit. Each droplet is 5 ?m in diameter and contains 1 to 3 bacilli. Close contacts (people with prolonged, frequent, or intense contact) are at highest risk of becoming infected (typically a 22% infection rate). A person with untreated, active tuberculosis can infect an estimated 20 other people per year. Others at risk include foreign-born from areas where TB is common, immunocompromised patients (eg. HIV/AIDS), residents and employees of high-risk congregate settings, health care workers who serve high-risk clients, medically underserved, low-income populations, high-risk racial or ethnic minority populations, children exposed to adults in high-risk categories, and people who inject illicit drugs.

TB most commonly affects the lungs (75% or more), where it is called pulmonary TB. Symptoms may include a productive, prolonged cough of more than three weeks duration, chest pain, and hemoptysis. Systemic symptoms include fever, chills, night sweats, appetite loss, weight loss, and easy fatigability. The term consumption arose because sufferers appeared as if they were "consumed" from within by the disease. People from Asian and African descent may have lymph node TB more often than Caucasians.

For all practical purposes, only patients with tuberculosis of the lungs can spread TB to other people. People may become infected with TB but not have active disease: such people are said to have latent TB infection (LTBI) and are not capable of passing the infection on to other people. The reason for treating people with LTBI is to prevent them from progressing to active TB disease later in life (approximately 10% lifetime risk). The distinction is important because treatment options are different for the two groups.