Infectious Disease

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Let's look at each question for Tuberculosis from various sources, which you can draw on for your final report.

Tuberculosis

a. Describe the agent of disease.

Tuberculosis is an infection disease caused by a group of bacteria, the Mycobacterium tuberculosis (MTB) complex, which includes M. tuberculosis, M. bovis, M. africanum and M. microti, of which the first three are important in human infection. Tuberculosis, or TB most commonly affects the lungs (Public Health Organization of Canada, 2003).

b. Describe the factors that make this particular population vulnerable to the disease.

In healthy people, infection with Mycobacterium tuberculosis often causes no symptoms, since the person's immune system acts to "wall off" the bacteria. The symptoms of active TB of the lung are coughing, sometimes with sputum or blood, chest pains, weakness, weight loss, fever and night sweats. Tuberculosis is treatable with a six-month course of antibiotics (World Health Organization, 2007).

People with diseases with compromised immune systems are especially vulnerable, such as people who are tested as HIV-positive. HIV and TB form a lethal combination, each speeding the other's progress. HIV weakens the immune system. Someone who is HIV-positive and infected with TB bacilli is many times more likely to become sick with TB than someone infected with TB bacilli who is HIV-negative. TB is a leading cause of death among people who are HIV-positive. In Africa, HIV is the single most important factor contributing to the increase in incidence of TB since 1990 (World Health Organization, 2007).

c. Describe environmental factors that make the population vulnerable to the disease.

? Some of the risk factors for infection that ar environmental include of spatial proximity to a patient with infectious TB, for example in a household setting, and through the same mechanism homelessness, imprisonment and certain occupations, such as work in a hospital. Also, environments of shared IV drug user who have test positive for HIV-positive.

d. What are the modes for disease transmission?

It is transmitted from person to person via droplets from the throat and lungs of people with the active respiratory disease.
Generally, TB is transmitted through inhalation of TB bacilli (MTB complex) in the air, and rarely through ingestion (of infected milk) or dermal implantation. Patients with pulmonary or laryngeal TB discharge the TB bacilli into the air when they
cough, sneeze, talk and sigh (Public Health Organization of Canada, 2003).

For example, patients with active pulmonary or laryngeal TB can transmit the bacteria to others as long as they are discharging tubercle bacilli in their sputum. Generally, when TB patients start adequate and appropriate treatment, their sputum becomes free of bacilli within a few weeks (Public Health Organization of Canada, 2003).

e. What methods are used to control the spread of the disease?

There are several proposed strategies for TB prevention and control programs, including:

1. Identifying and treating individuals who have active TB.
2. Finding and screening individuals who have had contact with TB patients to determine whether they are infected with M. tuberculosis or have active TB, and providing appropriate treatment.
3. Screening populations at high risk for TB infection and the development of TB disease to detect infected persons and provide therapy to prevent progression to active TB (Public Health Organization of Canada, 2003).
4. Prevention techniques- The tuberculosis vaccine, known as bacille Calmette-Guérin (BCG) may prevent the spread of tuberculosis and tuberculous meningitis in children, but the vaccine does not necessarily protect against pulmonary tuberculosis. It can, however, result in a false-positive tuberculin skin test that in many cases can be differentiated by the use of the QuantiFERON-TB Gold test (E-Medicine ...