Tuberculosis (TB) is one of the most contagious diseases. According to Kremer, Ballard, Estaquier, Poulain-Godefroy, and Locht, TB kills more people than any other infectious disease (1). An especially disturbing issue is that it has been on the resurgence in the recent past. This problem has been compounded by the emergence of drug-resistant strains. The causative agent of TB is known as Mycobacterium tuberculosis (Mtb) (National Institute of Allergy and Infectious Diseases (NIF).
Although lungs are the most commonly attacked body parts, this deadly disease can attack other organs in our bodies. XDR-TB (Extensively drug-resistant tuberculosis) is a strain of TB that is resistant to most potent drugs. Majority of patients suffering from XDR-TB do not recover. For the lucky ones, treatment follows a strict schedule of drugs that may take six months to two years (NIF). Therefore; it is wise to prevent people from getting into contact with the XDR-TB bacteria. Frequent tests and isolation of victims are some of the most effective ways of keeping people safe. This paper gives a detailed analysis of XDR-TB.
Like any other form of TB, XDR-TB is caused by Mtb. Infected persons introduce these bacteria into the air through coughs and sneezes. A point to note is that TB bacterium is only spread by people with active Tuberculosis. Interestingly, this bacterium can stay in the air for an extended period. Studies have shown that Mtb can survive in the open for seven hours, depending on the weather conditions (Center for Disease Control and Prevention (CDC)).
For one to develop active TB, Mtb must enter the body. This takes place when an individual breathes in air contaminated with it. The bacteria later moves into the lungs and begins its growth. Mtb later multiplies and attacks other body organs. This microorganism acts quickly since it is easily transported through the blood from one body part to the other. It is worth noting that the immune system cannot prevent Mtb from multiplying and spreading after the initial infection (NIF). The success of Mtb is, thus, greatly contributed by its unique characteristics and its ability to move from one part of the body to the other with ease.
Around 1/3 of the global population is infected with the TB bacteria (CDC). Luckily, only a few of the infected people develop full-blown TB. TB of the lungs, pulmonary TB, is the most contagious form of TB. This explains why 75 % of all TB infections are related to the lungs. XDR TB is one of the less common forms of drug-resistance TB. It occurs after Mtb becomes resistant to powerful antibiotics. Isoniazid and rifampin are some of the most potent TB antibiotics (Ruger). XDR TB is spread like any other type of TB (CDC). One of the ways through which it is dispersed involves inhaling the XDR TB bacteria.
Also, failure to follow a treatment regime or unreliable TB treatments leads to an XDR TB infection. The disease is also popular with people who develop TB after overcoming an earlier infection. Ruger adds that individuals suffering from diseases that weaken the immune system are prone to XDR TB, too (6). This explains why this killer disease is most prevalent in patients suffering from HIV and AIDS. Symptoms of active TB include “cough, loss of weight and appetite, fever, chills and, bone pains, and night sweats” (NIF par.7). Other symptoms depend on the part of the body affected.
There has not much success in treating XDR TB. Companies are yet to produce an effective vaccine or drug to contain XDR-TB since the market is not large enough to guarantee any returns (Ruger). This is disheartening as TB is very infectious and can spread globally in a short period. TB control programs show that only around 30% to 50% of infected people are treated and cured. Successes of this treatment depend on the severity of the diseases and the degree to which XDR TB bacteria is resistance to drugs.
Strength of a person’s immune system and his adherence to a treatment schedule can also dictate whether he will recover from XDR TB or not. An experiment by Kremer et al. showed that green fluorescent protein (GFP) is an appropriate reporter gene for mycobacteria (1). GFP can, hence, identify drug-resistant strains of Mycobacterium tuberculosis in our bodies. This is a step in the right direction in as far as the treatment of these strains is concerned. The TB bacteria can be detected in a day or two after infection. However, gauging the susceptibility or resistance of the bacteria to drugs takes longer as it has to be multiplied and verified in a specialized laboratory (CDC). Final diagnosis of XDR TB bacteria may take up to twelve weeks.
Although the authorities cannot compel individuals to undertake XDR-TB tests, it is appropriate for people to take baseline and follow-up skin tests (Ruger). People with a weak immune system and those exposed to the bacteria are highly recommended to undergo these tests regularly. Latent TB patients, people who have the Mtb in their body, but do not develop symptoms must also seek appropriate treatment. Studies indicate that 10% of individuals with latent TB develop active TB (NIF). Isolating infected people is also a sure way of preventing people from coming into contact with XDR-TB bacteria. Also, there are laws directing on how to treat and contain the spread of XDR-TB. The TB, vaccine, Bacille Calmette-Guérin (BCG) can suppress XDR-TB (CDC). However, BCG is effective in preventing TB in children only. Therefore, the vaccine cannot be recommended as an effective way of controlling XDR-TB. Avoiding contact with TB bacteria is the best way to prevent an infection.
XDR TB is one of the most dangerous diseases. Its ability to stand against potent drugs makes it very difficult to treat. Also, TB treatment options are very old due to the failure of pharmaceutical companies to invest in new drugs and vaccines. For that reason, most victims do not survive an XDR TB onslaught. Modern scientific methods such as the use of reporter genes have proved important in identifying drug-resistant strains of TB. For instance, GFP genes are crucial in the fight against this killer-disease. Simple ways of preventing contact with the XDR TB have also helped in its control. The threat posed by infectious agents such as XDR TB virus can cripple global and domestic economies. Furthermore, they utilize resources which could otherwise be utilized in other meaningful things. Controlling them can, hence, make the world an even better place to live in.
Center for Disease Control and Prevention (CDC). Fact Sheet: Extensively Drug-Resistant Tuberculosis (XDR TB).n.d. Web.
Kremer, Laurent, Baulard Alain, Estaquier Jerome, Poulain-Godefroy Odile and Locht Camille. “Green Fluorescent Protein as a New Expression Marker in Mycobacteria”. Molecular Microbiology 17.5 (1995): 913-922. Print.
National Institute of Allergy and Infectious Diseases (NIF). Tuberculosis (TB).n.d. Web.
Ruger, Jennifer Prah. “Control of Extensively Drug-Resistant Tuberculosis (XDRTB): A Root Cause Analysis.” Global Health Governance 3.2. (2010). Web.