Tuberculosis is both a dangerous and an infectious disease. A bacterium known as mycobacterium tuberculosis causes the illness. The disease attacks lungs but can also affect other organs of the body. The disease has become rare in developed countries but remains a significant epidemic in the middle and low-income countries. An estimated one and a half million people perish from the disease annually globally (Varaine & Rich, 2013). This makes it the highest killer disease in adults second from another infectious disease AIDS, with a majority of the deaths in low-income countries. Treatment remains a constant constraint to patients and a heavy burden for health care systems all across the world. With Tuberculosis being a significant killer disease, it is essential to study the causes, risks, treatment, diagnosis and developments, the health care system has made in an attempt to avert the condition.
Cause of Tuberculosis
Mycobacterium causes the disease, when allowed to grow within the body system. It takes long for the disease to develop after infection because the bacteria multiply slowly (Varaine & Rich, 2013). This bacterium mostly affects the lungs and soon spreads to other body organs. Its effect on the lungs causes pulmonary tuberculosis. The bacteria, which spread to other body organs, are the cause of extra pulmonary tuberculosis (Centres for Disease Control and Prevention, 2000).
Mycobacterium a small rod shaped bacteria about 2 to 4 um in length causes Tuberculosis and other diseases in humans (Varaine & Rich, 2013). Mycobacterium is ‘acid-fast organism’; a name health practitioner derived from the stains scientist and researchers use in the evaluation of tissue specimens. These bacteria are strictly aerobic and thrive in environments with an oxygen supply (Varaine & Rich, 2013). Bacteria may remain latent for years in the secondary stage of infection, sometimes even for months or years. Active tuberculosis may occur weeks or even years after the primary infection (Reichman and Bhavaraju, 2008). The slow rate of occurrence is because of the slow multiplication of mycobacterium. Pulmonary Tuberculosis affects the lungs; it is common in patients with HIV/AIDS because their antibodies are weak to resist disease. This TB spreads to other body organs during a silent phase of the ailment, often in the early stages of infection. Active TB can occur in other the body organs such as lymph nodes, vertebrae, kidney, genital organs and abdominal cavity (Zahrt, 2000).
It is possible to grow tuberculosis bacteria in laboratories. Medical researchers grow the bacteria in laboratories to study it and form analyse the resistant to drugs of the bacteria. This bacterium grows faster in a blood agar than an egg based medium. For this reason, many researchers who grow the bacteria in laboratories use the blood agar (Eichbaum, & Rubin, 2002).
Tuberculosis is an airborne disease, which pass from one person to the other through respiration. The source of infection is a person with pulmonary or laryngeal tuberculosis. These are the only types of Tuberculosis that spread. Extra pulmonary tuberculosis is not a transmittable disease. The reason pulmonary tuberculosis and laryngeal tuberculosis are transmittable is because they are in the lungs and larynx respectively. As a result, bacteria encounter air exhaled during coughing, conversations, sneezing or even normal breathing. During these activities, an infected person produces tiny infectious droplets of bacteria. These droplet nuclei are about one to five microns in diameter. The droplets can remain suspended in the air for several hours, depending on the environment. Transmission occurs when one inhales these droplets. Other causes are rare, such as Mycobacterium Bovi transmitted through cowmilk. Children are less likely to transmit tuberculosis because of the weaker sputum in their coughs and low bacillary load (American Thoracic Society, 1999).
People at Risk
HIV/AIDS patients and children are at a higher risk of acquiring Tuberculosis because their body immune systems are weak to handle the bacteria. HIV/AIDS weakens the body immune system making people vulnerable to this disease. Another vulnerable group to the disease is the women. Worldwide, women bear a heavy burden of poverty, poor health and disease. Females are at a high risk of HIV/AIDS infection because, in most instances their men are not faithful, and have multiple relationships. As a result, young women aged between fifteen years to twenty-four years of age with tuberculosis outnumber young males. Poverty is the main cause of high tuberculosis prevalence among women. (Centres for Disease Control and Prevention, 2000).
Signs and Symptoms
Some people do not show any signs for active tuberculosis. Others develop coughs with blood tinged mucous, fever night and appetite loss. These symptoms arise due to the bacteria using up oxygen in the body. This leads to coughs and shortness of breath. In some people, there are no symptoms because the bacteria have a slow progression process. This lengthens the latency stage of the bacteria. In the latent stage, the bacterium is inactive and does not show any signs (Handa, Mundi & Mohan, 2012).
There are several diagnostic methods for tuberculosis among them sputum smear microscopy, and staining method. Sputum smear method allows rapid and reliable identification of patients with pulmonary tuberculosis if the bacilli sputum concentration exceeds five thousand bacilli per millilitre (American thoracic Society, 2000). Reliability of the sputum depends on the quality of sputum. Taking sputum in the morning yields more reliable results than at any other time because at night one rarely spits sputum since they are asleep. This makes the sputum produced in the morning highly concentrated with bacilli. The reason why health practitioners use sputum spread method to test for pulmonary tuberculosis is that sputum passes through the trachea and is likely to contact bacilli. The staining method is another diagnostic that medical practitioners use. This method uses a technique where mycobacterium retains a primary stain after exposure to decolourising acid-alcohol. The two staining methods that nurses and other health practitioners use most of the times are carbolfulshin procedure and flouro-chrome methods (Partners in Health, 2003). The two methods work best in high load laboratories. The reason why doctors use the red-stain method is that this strategy can detect even other forms of tuberculosis besides pulmonary tuberculosis (World Health Organization, 2011).
The first step towards preventing Tuberculosis is to identify the main cause. An individual contact is the main method of transmission of the epidemic (Maher, 1997). Majority of the people who spread this disease are undiagnosed and do not know that they are ailing. This makes it necessary for governments and health systems to create tuberculosis awareness campaigns to let people know the importance of testing for tuberculosis. This will help identify an individual with the disease and inform them on the transmission methods. Awareness programs offer insight into preventive measure one can take to safeguard him or herself from this disease.
Treatment of tuberculosis involves taking quadruped drugs, isoniazid, rifampicin, and pyrazinamide and Ethambutol, under the supervisions and direction of a qualified medical practitioner for six months (Centres for Disease Control and Prevention, 2003). Mycobacterium tuberculosis has a thick fat coating, which makes it difficult to kill the bacteria. Recent studies have found an antibiotic that can kill the bacteria after destroying it thick cover. Pryidomycin, an antibiotic produced from the bacterium Dacylosporangium fulvum is the antibiotics, which has given many doctors and tuberculosis patients the hope of killing tuberculosis bacteria. In active bacterium, pylidomycin depletes fatty acids and mycolic acids that form the walls of the bacteria. This makes it possible for the antibiotic together with antibodies to kill the bacteria (Hartkoorn, et al., 2012).
About ninety percent of individuals infected do not show any signs of the disease, a situation known as latent infection. If the disease is untreated about a half or third infection cases, will die from the disease while early treatment cures the disease. About ninety-five percent of the deaths are from low-income areas. This is because of lack of resources to treat the disease among this segment of society. This makes it impossible for patients to access medical treatment, which results in many deaths (Varaine & Rich, 2013).
Research and Development in Tuberculosis
The first major breakthrough in combating tuberculosis was identifying the causes and transmission methods. This led to public measures and awareness. The discovery of ways to grow the bacteria in laboratories and development of tuberculin skin test and x-ray imaging were major developments in the nineteenth and twentieth century. Recent studies have elicited how Mycobacterium tuberculosis becomes dormant when its environment becomes hostile (Takenami, et al, 2013). When the bacteria are in a dormant state, they appear to be resistant to common anti-tuberculosis medications. New drug development procedures now test potential agents against both active and inactive forms of the bacilli (Perkins & Cunningham, 2007).
Gene array studies are showing that bacterial molecules and molecular pathways can be targets of potential new drugs. Researchers are currently testing several medicines developed this way (American Academy of Paediatrics, 2012). This is centrally to what was possible in the early years where the health practitioners knew almost nothing about the condition. Treatment was not possible during that time since even the cause of the disease was a mystery to people.
Since research has unearthed more information about the bacteria, newer, faster, and more accurate tuberculosis diagnostic methods are replacing old methods. These new techniques also give clues to how the human immune system deals with infection. Unravelling the genetic sequence of the bacteria has fostered the development of gene amplification tests that can diagnose the disease and detect drug resistance. These techniques can accomplish in hours or a few days what medical practitioners used to take weeks, thus reducing the chances of a person spreading the disease before diagnoses and treatment. This development marks the milestones taken in fighting this disease. In the past, this was not possible since the old methods were slow and inaccurate, which resulted to false diagnosis. This is probably the reason as to why it was extremely difficult to treat and control the spread of tuberculosis in the past. In terms of vaccination, researchers have made remarkable developments ever since the first discovery of the first tuberculosis vaccine, Bacilli Calmettte-Guerin, which French researchers developed in 1921 (Wang, et al, 2002). Contrary to Bacilli Calmette-Guerin Vaccine, modern vaccines work in different places. It is essential to realize one of the weaknesses of Bacilli Calmette-Guerin vaccine is it did not work in all geographical areas (Andersen, et al, 2000; Shelburne, et al, 2002).
In conclusion, tuberculosis is a significant epidemic and killer disease in the world. The disease had greatly reduced to low levels in the past, but with the high prevalence of HIV/AIDS the disease has returned. Developing countries account for about ninety percent of the disease because of poverty, malnutrition, deficiency of health care services and lack of awareness on the disease. Tuberculosis has existed for thousand years; during this time, researchers have made tremendous progress in the fight against the disease.
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