Tuberculosis Term Paper

Tuberculosis [...] tuberculosis as an emerging infectious disease. Tuberculosis is not a new disease, and the fact that it still exists in the world illustrates the tenacity of this infectious disease and the difficulties in continually treating and eliminating these types of diseases. Tuberculosis continues to kill millions of people each year and scientists are attempting to find new cures for the disease as it spirals out of control into one of the worst health menaces facing our world today.

History of Tuberculosis

The scientist Robert Koch first discovered the disease tuberculosis (TB) in humans in 1882. There is also a bovine form of the disease that is effectively controlled in areas that thoroughly pasteurize milk and practice more efficient health care in cattle. Birds can also carry a type of tuberculosis that can affect humans. Before its discovery, tuberculosis was known by a variety of names, including the most popular, "consumption," which was thought to be a wasting disease that affected the lungs. Tuberculosis is most known as a lung disorder, but it can also affect the intestines, bones and joints, the skin, and the genitourinary, lymphatic, and nervous systems, though less frequently than the lungs. The disease is caused by mycobacteria or tubercle bacilli in the case of human infection.

The first anti-TB treatments were developed in 1944, and the disease began to abate throughout the world until the mid 1980s, when the disease began to make a reemergence in the world. Between 1984 and 1992, the disease increased by 20% around the world, and today, the disease infects at least one-third of the world's population ("Tuberculosis"). In fact, the World Health Organization (WHO) calls tuberculosis a "global health emergency" (Editors), and is struggling with ways to combat the disease. Tuberculosis, once thought to be a disease of the past, is now again emerging as one of the world's most dangerous and resilient infectious diseases, and new ways to combat the disease must be developed in order to keep it from spreading even farther in the future.

While tuberculosis can affect several different areas of the body, it most often affects the lungs. The bacilli can survive for quite some time in the air or on dust, and TB "is an airborne disease, which can be spread by coughing, sneezing, talking or spitting" ("Airborne Disease" 73). Simply put, another person inhales the diseased droplets, some of the airborne bacilli can infect the new person's lungs, and the disease spreads. Someone infected with the disease can spread it to as many as 10 or 20 people a year, who in turn can spread it to as many others, so it is easy to see how it can spread so quickly. Out of those 10 to 20 a year, two to four will actually develop the disease.

Unfortunately, TB has proved to be quite resistant to treatment drugs, and it continues to develop new drug-resistant strains as drugs are created or improved, so eradicating the disease has proved especially difficult, especially in the third world, where health care is often spotty at best. Even more alarming, "Some believe that unless major new treatment strategies are initiated in source countries, drug-resistant TB will eventually become epidemic even in areas with good control programs, such as Europe and America" ("Tuberculosis"). Tuberculosis is still an extremely deadly disease that kills more people each year than "any other curable disease" (Editors). Clearly, the world must band together to discover an effective way to combat this disease before it creates even more havoc in the health and welfare of the world's population.

Diagnosis of the Disease

In its early stages, tuberculosis is quite difficult to detect, and patients may simply see the symptoms as a cold or other light respiratory infection. A lesion, called a "tubercle" that eventually calcifies, characterizes the disease. Often, the infection stops permanently at this point, and the patient never has another occurrence. In others, the disease can break out much later, often years later, when the body's immune system is weakened by some other infection or problem. Therefore, it is sometimes difficult to diagnose the disease, and it can go untreated as a result. "Untreated, the infection can progress until large areas of the lung and other organs are destroyed. Symptoms of the disease include cough, sputum, bleeding from the lungs, fever, night sweats, loss of weight, and weakness" ("Tuberculosis").

Actual diagnosis of the disease begins with a tuberculin skin test. If the skin test is positive, confirmation from chest x-rays and a sputum examination completes the diagnosis ("Tuberculosis").In addition, about one-third of the 40 million people worldwide who are infected with HIV are also co-infected with TB (Editors). Because of this, many clinics now treat HIV and TB simultaneously. Once the disease has been correctly diagnosed and confirmed, treatment can begin.

Treatment of the Disease

In an ideal situation, treatment for the disease begins after the skin test shows exposure to the disease, but before the actual disease develops. Treatment usually consists of the antimicrobial drug isoniazid (INH), which has been in use against TB since 1956. If the disease is already in progress, INH is often used in concert with other antituberculosis drugs such as rifampin, pyrazinamide, and ethambutol ("Tuberculosis"). Treatment is not difficult, but the major problem with treatment is that it takes time, and many patients stop taking their drugs after they begin to feel better, but for the treatment to fully work, the drugs need to be taken for a long-term, typically six months to a year, and this is often difficult for patients. Similarly, preventative treatment can also be abandoned because of the length of treatment or inconvenience of treatment, and this adds to the spread of the disease. Many researchers believe this abandonment of treatment is one reason why TB is able to build up resistant strains that are immune to certain drugs. It allows the bacilli to build up immunity to a drug or drugs, and then the bacilli are spread to the next victim. As tuberculosis builds up drug immunities, it becomes much more difficult to treat and eradicate.

Unfortunately, these immune strains of TB also lead to higher death rates. Simplifying the dosage can help keep patients on treatment for longer treatments, and "The combination drug rifater (rifampin, isoniazid, and pyrazinamide) has simplified drug administration" ("Tuberculosis"). Sometimes, health care workers monitor the dosages to make sure patients get the dosage each day for the allotted time, but this is not always practical or feasible. Clearly, early diagnosis and treatment of the disease is key to the prevention and spread of the disease. TB can be cured, but the disease must be diagnosed and treated to be cured, and people must be educated about the treatment and prevention of the disease.

Prevention of the Disease

Because TB is such a virulent and contagious disease, WHO has dedicated a large part of its resources to worldwide education and prevention of the disease. TB can be cured, but because of the difficulty of diagnosis and continued treatment, prevention is the best way to cure the disease. However, with TB so prevalent around the world prevention is difficult.

In areas where there are large concentrations of people, many measures that can help prevent the disease, including strictly regulated ventilation systems, air filtration, and "isolation methods in hospitals, medical and dental offices, nursing homes, and prisons" ("Tuberculosis"). Those infected with the disease need to be isolated from others, and if a person has come in contact with someone with TB, preventative antibiotics need to be administered as soon as possible.

The French developed an antituberculosis vaccine called bacille Calmette-Guerin, or BCG, in 1908, but it is not widely used in the United States because there has always been "conflicting evidence as to its efficacy (it appears to be effective in 50% of those vaccinated)" ("Tuberculosis"). This vaccine, however, is administered to over 80% of children in the world, usually in the countries where it is most common, such as Africa and Asia. Scientists and officials agree that it is time for a new vaccine must be developed to combat and prevent TB. "It is hoped that the determination of the complete DNA (genome) sequence of Mycobacterium tuberculosis, achieved in 1998, will hasten the development of an effective vaccine" ("Tuberculosis"). WHO has created a program known as DOTS to help combat the spread of the disease around the world. They are also funding scientific programs to develop drugs that can eliminate the disease faster, and is working to develop new and faster diagnostic tools to identify the disease more quickly and effectively.

Elimination of the Disease

The saddest part of the TB epidemic is that it could have been largely prevented, had we actually eliminated the disease by the mid-60s in the United States, as most people thought it was. Unfortunately, funding for further study and treatment of the disease virtually dried up during this time because most people thought the disease had….....