On this World Tuberculosis Day, we reflect on the impact of this debilitating disease throughout the ages. It was the dawn of the industrial age in the West that brought about a rise in deaths from TB as the unhealthy conditions of poor sanitation, housing and nutrition allowed this disease to flourish. It was the leading cause of death in Europe and the United States from the eighteenth into the twentieth century. It was called “consumption” by the way it seemed to consume the person from within. It has been a subject of tragic operas (Violetta in “La Traviata” and Mimi in “La Bohème”), classic literature, (Fantine in “Les Misérables”, Andy in “A Tree grows in Brooklyn”) and in art, it is represented by a moving portrayal by Edvard Munch of his sister who died of this disease at the age of fifteen (currently here at the Museum of Modern Art in New York). As prosperity – more than modern medicine – developed, the rate of TB deaths became rarer and by the nineteen fifties very few people in the West were dying of the disease.
However, TB continues to be a major global health concern and continues to spread especially in countries where poor, unsanitary conditions still exist. Statistics show that nearly 1 billion people will be infected with TB globally in the world by the year 2020. Just in the United States alone a total of 10,521 new cases of TB were reported in 2011 which shows a marked increase on previous years.
What is Tuberculosis?
TB is an infectious disease that is caused by a bacterium called MYCOBACTERIUM TUBERCULOSIS that primarily affects the lungs. The bacteria in the lungs multiply and cause pneumonia along with chest pain, prolonged coughing and hemoptysis or coughing up of blood.
As TB is an airborne bacterial infection it is commonly spread by droplets of mucus secreted by those infected, such as through coughing, sneezing and even talking. These droplets can be particularly contagious in small, confined spaces as they can remain suspended in the air and inhaled by others.
What are the symptoms?
There are two types of TB, one is latent which means that the patient does not have symptoms and is therefore not contagious, and the other is active. Patients with active TB show symptoms of cough, chest pain, fever, fatigue, night sweats, shortness of breath as well as loss of appetite and weight loss. The cough typically may start as a dry cough but later becomes productive and may be blood-tinged, as made famous in those tragic operatic tales and classic novels and films of the past.
How to test for TB?
The TST is a commonly used tool to screen for tuberculosis and one that we perform at every immigration exam. This involves an injection of 0.1ml. of tuberculin purified protein derivative (PPD) in the forearm. After 48 to 72 hours the skin’s reaction to the test has to be measured and if positive radiology exams and then antibiotic treatment are carried out. Sometimes false positives are read due to cross-reactivity with the bacillus Calmette-Guerin (BCG) vaccine given in some countries. A chest x-ray is then ordered to rule out the infection.
A modern alternative to the TST is the QuantiFERON –TB Gold in-Tube test (QFT). This is a highly-specific controlled blood test for detection of immune responses to TB infection in whole blood. It provides clinicians with an accurate and efficient tool for the diagnosis of both strains of TB. It can be done in the doctors’ office and the results are much faster. This will eventually replace the conventional TB.
What are the Treatment Options?
Today there are several drug therapies that may last many months or even years. An antibiotic called Isoniazid (INH) is prescribed for six to twelve months, as well as drugs such as rifampin, ethambutol and pyrazinamide and streptomycin if the disease is extensive. In severe cases, surgery is performed to remove damaged lung tissue. In December 2012 the FDA approved Sirturo (bedaquiline) as part of a combination therapy for adults with multi-drug resistant TB. This is the first TB drug to be approved in the US in forty years.
How to avoid TB?
The most important thing is to take care of your immune system, eat a healthy diet and if you work or live in a high risk environment or return from an infected region you should get regularly tested for TB.
Dr Albert Levy
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