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TB Assignment

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What type of organism cause TB? Mycobacterium tuberculosis is the organism that is the causative agent for Tuberculosis (TB). M.tuberculosis organisms are also sometimes called "bacilli". Other atypical mycobacteria exist, such as M.avium, M.intracellularae, M.kansasii, M.xenopi and M.fortuitum. These may appear to produce similar clinical and pathological appearance of the disease, this is because they all belong to the same family of mycobaterial organisms. Most infections with these organisms are believed to arise from the environmental exposure to organisms; infected water, soil, dust or aerosols. Person to person and animal to animal transmissions of atypical mycobacterium is not an important factor in acquisition of infection with the organisms. How is TB transmitted? Tuberculosis is an airborne disease. A person with the infection of TB in their lungs, or larynx, can release droplets when the cough, sneeze, talk or even breathe. The droplets contain the organism mycobacterium tuberculosis, the organism which causes the infection and are called droplet nuclei. If these droplet nuclei are inhaled by an uninfected person, who shares the same airspace as the infected person, he/she will be infected. ...read more.


a person to become infected after being exposed, varies from weeks to years, depending on the individual and whether the infection is primary, progressive or reactivation TB. Primary TB occurs when a person first becomes infected, this is when the body forms Tubercles on the lungs to contain bacteria; there are rarely symptoms with primary TB. Progressive TB is usually associated with Th2 T-cell response whereas a pure Th1 response mediates protection. Whereas in reactivation TB, the primary infection has resolved, but the bacteria are dormant or hibernating. When conditions become favourable for the bacteria, they become active again. * The incubation period for this disease is a setback as this means that the carrier could have the disease for weeks-years and pass it on to many people without knowing that the are doing so. Diagnosis of TB, and how it is treated. * Symptoms of TB include: a persistent cough (usually for more than three weeks, at first may be dry and then is accompanied by sputum that may be blood-streaked, along with night sweats, weight loss, fever and tiredness. ...read more.


What is the annual incidence of TB and where is the disease problematic? * "Incidence" is the frequency of new occurrences of disease within a defined time interval. Incidence rate is the number of new cases of a specified disease divided by the number of people in a population over a specified period of time, usually one year. Therefore the incidence of Tuberculosis refers to the annual diagnosis rate or the number of new cases of Tuberculosis diagnosed each year. These two statistic types can differ; a short lived disease like flu can have a high annual incidence, but a life long disease like diabetes has a low annual incidence. * Problematic countries where the incidence rate is high include India, where it was estimated to have 1, 835, 000 new case of tuberculosis in the year 2000. Also China has a high incidence rate; this was estimated to be at 1, 365, 000 new cases in the year 2000. The disease becomes more problematic in the lesser developed countries where they do not have the sufficient medical equipment and technology to vaccinate against it. ...read more.

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