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TB Infection

Sharhea's picture

Tuberculosis (TB) also known in the medical world as tubercle bacillus, is a deadly infectious disease caused by Mycrobacterium tuberculosis. When I was twelve years old, I had to get a set of shots so I could begin middle school in America. I had no idea what any of these shots were called, I was just aware that they were necessary for me to continue my education. As any normal teenager/adolescent, I was a little scared of needles, and had no idea and/or concern for what these shots may or may not prevent. The medical terminology in those years was of total disinterest to me. One of those shots that I had to take is what I now know as a Tuberculosis or PPD Skin Test.


The Purified Protein Derivative (PPD) Skin Test is also known as the Mantoux test. A small amount of PPD Tuberculin is injected in the skin on the inside forearm. PPD is “an antigen - a substance that stimulates the immune system to eliminate or fight foreign substances in the body. PPD is taken from dead tuberculosis bacteria.”[1] I felt a little prick and the nurse placed two dots with permanent marker, to mark where she injected the PPD. I was told to return within a week, so the doctor can exam the area. I was also told that if the area becomes a rash to return earlier than a week for further testing. I did return to Boston Children Hospital with a rash on the inside forearm. Next came a series of chest X-rays and blood work. My mother and I had to answer a series of questions about our family history, places I have lived etc, for the doctors to find a source of how I got exposed to the bacterium. The tests revealed that I have the TB infection but not active, inactive or latent tuberculosis. I was told that I had to take a pill daily for the next six to nine months.


Through this whole process I was still unaware of how serious this could be if I was actually positive with Tuberculosis. I had no idea that this disease could be deadly. Tuberculosis commonly attacks the lungs but can also attack the nervous system, the circulatory system, the bones, joints, etc… “Over one-third of the world’s population has been exposed to the TB bacterium, and new infections occur at a rate of one per second… one in ten latent infections will progress to active TB disease, which, if left untreated, kills more than half of its victim.”[2] TB, like the common cold, spreads through the air. People diagnosed with active TB in their lungs are very infectious. When infected patients “…cough, sneeze, talk or spit, they propel TB germs, known as bacilli, into the air. A person needs only to inhale a small number of these to be infected.”[3]


It was very crucial for me to follow the doctor’s orders about taking the medication daily. I later found out that the medication that the doctor recommended was INH (TB medication isoniazid). The INH was a preventive drug therapy that destroyed dormant bacteria that may become active in the future. As a teenager, I usually had much difficulty remembering to take the medication daily, but with my mother and grandmother on my back it became easier.


Tuberculosis has risen in the developing world and developed world with the rise in HIV infections. “The rise in HIV infections and the neglect of TB control programs have enabled a resurgence of tuberculosis.”[4] The table below shows the estimated TB incidence, prevalence and mortality in different regions for the year 2005:


Incidencea Prevalencea TB Mortality
  All forms Smear-positiveb        
WHO region number (thousands) per 100 000 pop number (thousands) per 100 000 pop number (thousands) per 100 000 pop number (thousands) per 100 000 pop
(% of global total)
Africa 2 529 (29) 343 1 088 147 3 773 511 544 74
The Americas 352 (4) 39 157 18 448 50 49 5.5
Eastern Mediterranean 565 (6) 104 253 47 881 163 112 21
Europe 445 (5) 50 199 23 525 60 66 7.4
South-East Asia 2 993 (34) 181 1 339 81 4 809 290 512 31
Western Pacific 1 927 (22) 110 866 49 3 616 206 295 17
Global 8 811 (100) 136 3 902 60 14 052 217 1 577 24

The World Health Organization (WHO) estimated that 1.6 million deaths resulted from TB in 2005. The highest number of deaths and mortality per capita occur in the African Region.


There are different treatment approaches for TB, whether it is isoniazid, rifampin and/or other drugs; the process takes months to years to completely kill the bacterium. It is very important for anyone who has been diagnosed to fully complete any treatment the doctor recommend. If anyone needs further information about the symptoms, treatment, risk factors etc…you should visit: or any of the links in my footnotes. They have a full description of the disease, getting tested and lots more information.   

[1] diseases;

[2] Tuberculosis;

[3] World Health Organization;

[4] Tuberculosis