PCP HIV AIDS Toolkit/Biology of HIV AIDS/Handout F: Tuberculosis and HIV AIDS
Handout F: FACT SHEET - Tuberculosis and HIV/AIDS
Tuberculosis (TB) is a chronic bacterial infection. It is spread through the air and usually infects the lungs, although other organs and parts of the body can be involved as well. With an estimated two billion people (one-third of the world‚Äôs population) infected, TB is one of the most common infections among humans, and a leading killer of adults worldwide.
Not everyone infected with TB becomes sick. There are two kinds of TB:
- Latent TB (TB infection) - Most people who are infected with TB have latent TB. They have no symptoms and are not contagious. The immune system isolates the TB bacteria which, protected by a thick waxy coat, can lie dormant for years. The risk of developing active disease is greatest in the first year after infection, but active disease can also occur many years after initial infection. When a person‚Äôs immune system is weakened, the chance of developing TB disease is greater. Five to ten percent of people with latent TB (but who are not infected with HIV) will develop active TB at some time during their lives. Latent TB infection can be treated so it does not become active TB disease.
- Active TB (TB disease) - People with active TB are sick (common symptoms: bad cough, chest pain, fever, weakness). Only people with active TB in their lungs are contagious. The bacteria are put into the air when a person with active TB coughs, sneezes, talks, or spits. People nearby may breathe in the TB bacteria and become infected. An untreated person may infect on average 10 to 15 people per year. Active TB is almost entirely curable. According to World Health Organization (WHO) estimates, each year, eight million people worldwide develop active TB and nearly two million die.
What is the relationship between HIV and tuberculosis?
Many of the world‚Äôs TB cases are latent, but they can become active when a person‚Äôs immune system is depressed as a result of other factors, particularly HIV/AIDS. HIV and TB form a lethal combination, each speeding the other‚Äôs progress. TB is a leading cause of death among people who are HIV-positive; it is estimated to account for greater than 30 percent of AIDS-related deaths worldwide. 
Although HIV has increased the incidence of TB, it is an infectious disease that is not confined to HIV-positive individuals. Because TB is spread through the air, an increase in active TB among people co-infected with TB and HIV results in:
- more transmission of the TB bacteria;
- more people with latent TB; and
- more TB disease in the whole population.
As one of the first opportunistic infections to appear in HIV-infected people, TB may be the earliest sign of HIV infection. For this reason, addressing TB offers the opportunity for early HIV intervention. HIV-positive people can be screened for TB. If they are infected they can be given prophylactic treatment to prevent development of the disease or curative drugs if they already have the disease. TB programs can make a major contribution to identifying eligible candidates for ARV treatment.
What is the impact of TB/HIV on women?
In most of the world, more men than women are diagnosed with active TB and die from it. TB is nevertheless a leading infectious cause of death among women. Annually, about three-quarters of a million women die of TB, and more than three million contract the disease. Since tuberculosis affects women mainly in their economically and reproductively active years, the impact of the disease is also strongly felt by their children and families.
While poverty is the underlying cause of much infection in rural areas, poverty is also aggravated by the impact of TB. In 1996, a study by the World Bank, World Health Organization (WHO), and Harvard University reported TB as a leading cause of "healthy years lost," among women of reproductive age.
What is being done to combat the spread of TB?
The internationally recommended approach to TB control is Directly Observed Therapy (DOT), an inexpensive strategy that could prevent millions of TB cases and deaths over the coming decade. The DOT strategy for TB control consists of five key elements:
- government commitment to sustained TB control;
- detection of TB cases through sputum smear microscopy among people with symptoms;
- regular and uninterrupted supply of high-quality anti-TB drugs;
- six to eight months of regularly supervised treatment (including direct observation of drug-taking for at least the first two months); and
- reporting systems to monitor treatment progress and program performance.
Once patients with active TB have been identified, health and community workers or trained volunteers observe patients swallowing the full course of the correct dosage of anti-TB medicines.
Testing is repeated after two months to check progress, and again at the end of treatment. The recording and reporting system ensures that the patient‚Äôs progress can be followed throughout treatment. It also allows assessment of the proportion of patients who are successfully treated, giving an indication of the quality of the program.
The DOT Strategy:
- produces cure rates of up to 95 percent even in the poorest countries.
- prevents new infections by curing infectious patients.
- prevents the development of drug resistance by ensuring that the full course of treatment is followed.
- is ranked by the World Bank as one of the ‚Äúmost cost-effective of all health interventions.‚Äù
Multiple Drug-Resistant TB (MDR-TB)
Until 50 years ago, there was no medication to cure TB. Now, strains that are resistant to a single drug have been documented in every country surveyed; what is more, strains of TB resistant to all major anti-TB drugs have emerged. Drug-resistant TB is caused by inconsistent or partial treatment, when patients do not take all their medicines regularly for the required period because they start to feel better, because doctors and health workers prescribe the wrong treatment regimens, or because the drug supply is unreliable. A particularly dangerous form of drug-resistant TB is multidrug-resistant TB (MDR-TB), which is defined as the disease caused by TB bacilli resistant to the two most powerful anti-TB drugs. Rates of MDR-TB are high in some countries, and threaten TB control efforts.
While drug-resistant TB is generally treatable, it requires extensive (up to two years) treatment that is often prohibitively expensive (often more than 100 times more expensive than treatment of drug-susceptible TB), and is also more toxic to patients.
What can Peace Corps Volunteers do?
Because Volunteers work at the community level, they are in a key position to spread awareness of TB and of the deadly relationship between TB and HIV. World TB Day, held on March 24 each year, is an occasion for people around the world to raise awareness about the international health threat presented by TB. This is just one of the opportunities Volunteers can use to raise awareness in their communities. People who have been cured of TB are excellent advocates; Volunteers can identify these people in their community and encourage them to come forward to speak of the benefits of treatment. Getting involved in TB-DOT programs to facilitate the control of TB in a village or region is important and is an area where Volunteers can help to train, facilitate, and share information on TB and HIV/AIDS. The co-infection of TB-HIV is an important area to focus HIV/AIDS activities to address the problem.
- World Health Organization. ‚ÄúWhat is TB? How is it spread?‚Äù http://www.who.int/features/qa/08/en/index.html (accessed March 12, 2007).
- National Institute of Allergies and Infectious Diseases. ‚ÄúTuberculosis.‚Äù http://www.niaid.nih.gov/factsheets/tb.htm (accessed March 12, 2007).
- Stine, Gerald J, Ph.D., AIDS Update 2007: An Annual Overview of Acquired Immune Deficiency Syndrome. New Jersey: Prentice Hall, pg. 129.
- Family Health International. ‚ÄúTuberculosis and HIV/AIDS.‚Äù http://www.fhi.org/en/Topics/Tuberculosis+and+HIV-AIDS+topic+page.htm (accessed March 12, 2007).
- World Health Organization. ‚ÄúTuberculosis and Gender.‚Äù http://www.who.int/tb/dots/gender/page_1/en/index.html (accessed March 12, 2007).
- World Health Organization. "Tuberculosis." http://www.who.int/mediacentre/factsheets/fs104/en/index.html (accessed March 12, 2007).