In order to successfully understand TB, its physiology must be understood. TB is brought on by Mycobacterium tuberculosis, “a strain with limited genetic diversity and no significant animal or environmental reservoir,” (Cook, et al., 2009, p. 41). Even without a known site where the bacteria are most prevalent, the bacteria can still be dangerous in small numbers as the bacteria are distinctly adept at and avoiding the immune systems of its host (p. 41). “M. tuberculosis is also able to adapt to very different intracellular environments including: phagosomes in macrophages and dendritic cells, granulomas and even fat cells,” (p. 41).
Phagosomes are vesicles which form around pathogens and ultimately destroy said pathogens (Tessema, Koets, & Rutten, 2011, p. 157). In order to fully achieve its goal of eliminating the pathogen a phagosome must fuse with a lysosome. Once fused, enzymes contained within the lysosome work at digesting/eliminating the pathogens contained within the phagosome (pp. 157-158). M. tuberculosis is skilled at preventing this fusion allowing the bacteria to successfully avoid detection by the immune system (pp. 159-160).
Granulomas are collections of macrophages used to separate the body from foreign particles (p. 158). Granulomas containing M. tuberculosis have necrosis, meaning that the cell will eat away and degrade the surrounding tissues (p. 158). The TB disease is extremely dangerous and fatal if left untreated, and with the various drug-resistant strains in the world the need for worldwide awareness of TB is vital.
In order to determine if someone has TB one can take a TB skin test or a blood test. These are preliminary tests, so if someone tests positive for TB then a physician can provide other forms of testing to determine if the person infected is latent or has the disease. Treatment of latent TB involves the use of antibiotics such as isoniazid (INH), rifampin (RIF), and rifapentine. When treating the TB disease medications used include INH, RIF, ethambutol (EMB), and pyrazinamide (PZA) (CDC, 2014, p. 1). These drugs seek out and kill the mycobacterium (p. 2). The most effect drugs in combatting TB are isoniazid and rifampicin, “Isoniazid, the most powerful mycobactericidal drug available, ensures early sputum conversion and helps in decreasing the transmission of TB. Rifampicin, by its mycobactercidal and sterilizing activities is crucial for preventing relapses,” (Sharma & Mohan, 2004, p. 355).
There haven’t been any new vaccines to treat TB for almost 80 years and research to create new vaccinations is ongoing (Montañés & Gicquel, 2011, p. 58). Some researchers are looking at improving the bacilli Calmette-Guerin vaccine (BCG). “Numerous subunit vaccines have been developed using different experimental approaches. The justification for these vaccines is that a few antigens can achieve the same protection that comes with the complete bacteria and...