Why it is more common is developing countries?
Based on these rates and estimates of the number of cases that remain undetected and untreated and the number that are detected and treated with standard chemotherapy regimens (World Health Organization (WHO), unpublished data), the estimated annual number of deaths from TB in the developing world is greater than 2,500,000 (Table 3), or approximately 6.7% of all deaths and, among persons 15-59 years of age, 18.5% of deaths and 26% of preventable deaths. Prevention and Control
Three major strategies for controlling TB are BCG vaccination of children, chemoprophylaxis, and case-finding/treatment.
Total coverage with BCG can prevent 40%-70% of deaths from TB among children and reduce total TB mortality by approximately 6% (1). However, because the effect of BCG on TB mortality is limited in older age groups, expanded BCG coverage cannot be the sole means employed to control TB.
Although clinical TB can be secondarily prevented by treating persons with latent tuberculosis infection, mass chemoprophylaxis of all such persons cannot be efficiently or economically accomplished. However, selective treatment of high-risk groups (e.g., close family contacts of smear-positive sources) may be feasible. If proven effective in clinical trials, chemoprophylaxis might also play an important role in preventing clinical TB in persons with dual human immunodeficiency virus (HIV) and tuberculosis infections. Treatment
The most effective means of reducing transmission of tuberculosis infection, and thus the number of TB cases, is to treat and cure patients with smear-positive TB. Each person with undiagnosed and untreated smear-positive TB will cause 10-14 infections per year. Of these, 0.6-1.2 eventually will become new cases of TB (1).
Despite the availability of anti-TB drugs, TB treatment programs in most developing countries have not succeeded because of poor patient compliance with therapy, emergence of drug-resistant organisms, and failure to carefully control drug supplies and therapy. Cure rates in developing countries are frequently less than 50%; however, cure rates of greater than 90% can be achieved when short-course chemotherapy regimens are given under supervision (7).
Why is it important to take all medication?
The recommended treatment and cure for TB is a strategy called DOTS (directly observed treatment, short course). DOTS cure TB up to 95% of the time, even in very poor countries.
People with TB disease need to take anti-TB drugs every day for at least six to eight months. Because it can be very hard to remember to take the right amount of medication every day for a long time, the DOTS method recommends that people go to a health centre for treatment every day to make sure that the person with TB swallows the correct dose of the right anti-TB medicines.
Usually, a person with TB will be given a combination of more than one of the following anti-TB drugs:
- ethambutol;
- isoniazid;
- pyrazinamide;
- rifampicin;
- Streptomycin.
Often, the drugs are conveniently combined into a single tablet, such as RMZ, which makes them easier to take.
After two months of treatment, another saliva sample is analyzed to make sure the drugs are working. At the end of treatment, a final saliva sample is analyzed to make sure the germs are gone.
Even if DOTS is not available in your area to give you medical support to follow the treatment schedule, remember that taking the correct dosage of the anti-TB drugs every day for the whole prescription period is very important if you want to be cured.
What are the symptoms for TB?
You may or may not have any symptoms depending on how your body reacts to the tuberculosis infection. Once you have been infected with the tuberculosis bacteria, one of three things could happen.
- You won’t have any symptoms because your immune system kills the bacteria and clears the infection.
- You will have symptoms because your immune system can’t clear the infection and the bacteria begin to grow in your lungs or other organs.
- You will get symptoms only if the infection is reactivated, which may be many years later. This is because your immune system builds a defensive wall around the bacteria, which is known as a latent infection.
If you have any symptoms of tuberculosis in your lungs, these can include:
- a persistent cough, which may produce phlegm with or without blood in it
- loss of appetite
- weight loss
- fever (high temperature)
- night sweats
- tiredness
- chest pain when you breathe in, caused by inflammation of the membranes lining your lungs (pleurisy)
You may have tuberculosis infection in a part of your body other than your lungs. Your symptoms will depend on where the infection is. You may have:
- swollen neck glands
- bone pain, joint pain and swelling, or back pain
- abdominal (tummy) pain
- confusion, problems with your vision or a persistent headache
- skin sores
- breathlessness and chest pain
- ankle swelling
These symptoms aren’t always caused by tuberculosis, but if you have them, see your GP
How do doctors know?
The most commonly used test for TB is a skin test called Mantoux test. In this test, a hypodermic needle is used to inject a small amount of purified TB protein called PPD tuberculin into the skin of the mid-forearm. Patients are asked to return to the doctor’s 48 to 72 hours later to have the result read. If the skin becomes a hard, raised bump at the injection site, this is a positive response and it indicates past exposure to TB. If there is no reaction, the result is negative, indicating that you have not been exposed to TB.
