The drugs must also be of quality. This is often not the case, as substandard anti-tuberculosis drugs are widely available on the market in man countries.
The World Health Organization is at this time assessing the quality of drugs produced by different manufacturers, an important exercise which should make possible developing countries to acquire pre-qualified drugs of guaranteed quality. Today, however, there are no pre-qualified sources of anti-tuberculosis drugs in formulations suitable for children, nor are there any pre-qualified sources of streptomycin, one of the drugs used against TB. TB disease can be treated by taking several drugs for 6 to 12 months. It is very important that people who have TB disease finish the medicine, and take the drugs exactly as prescribed. If they stop taking the drugs too soon, they can become sick again; if they do not take the drugs correctly, the germs that are still alive may become resistant to those drugs. TB that is resistant to drugs is harder and more expensive to treat. In some situations, staff of the local health department meets regularly with patients who have TB to watch them take their medications. This is called directly observed therapy (DOT). DOT helps the patient complete treatment in the least amount of time.
Strategies to Control TB
The cost-effectiveness of short-course drug therapy for TB has been central to the global promotion of directly observed treatment short course (DOTS) by the World Health Organization. However, the DOTS approach alone may not be sufficient to bring TB under control, and interest is growing in other methods, such as developing a more effective vaccine, treating latent TB infection, testing for TB drug resistance, treating HIV co-infection, and active case finding. It is not clear how money can be best allocated for TB control; although DOTS programs are a good value, their full cost may be greater in countries where a broader investment in the health sector is needed (Tuberculosis, Perspectives in Health, 2009).
Impact of Tuberculosis
TB is a disease of young people. This is due to the fact that the greatest predictor of disease due to TB is the amount of time that has passed since infection with TB, this risk being greatest within 5 years of first becoming infected with TB. Even in countries where TB is uncommon and most disease arises from remote infection, most individuals who will be infected become infected by the age of 20 years. The association of TB with youth makes this disease an important factor in the economy of many countries, which simultaneously experience a low gross national product and a high incidence of TB, because the disease affects the most economically productive sector of the economy.
As a result, an organized TB control program, unlike many other health-related activities, is a net contributor to economic development (Kaufmann and Hahn, 2003). Once infected with TB, women of reproductive age are more susceptible to developing active TB than men of the same age. As a result, in certain regions, young women ages 15 to 24 with TB outnumber young men of the same age with the disease.
Strategies to Prevent TB
Preventive measures BCG vaccination has limited application in developed countries where the incidence of TB is low. It is an effective vaccine in reducing TB meningitis and death in babies and children less than five years in countries of high TB prevalence. It is not recommended for general use in the Australian community but should be considered for specific high risk groups such as infants and young children traveling for extended periods to countries with a high incidence of TB (Communicable Diseases Section, Victorian Government Department of Human Services, 2005).
Bacille Calmette-Guerin (BCG) vaccine, a live attenuated preparation derived from Mycobacterium bovis, is given to approximately 75% of infants worldwide. It is estimated that the number of tuberculous meningitis and miliary TB cases prevented by BCG vaccination and calculated the cost of vaccination per TB case or death prevented and the cost per disability-adjusted life-year (DALY) gained. They used estimates of prevalence of smear-positive pulmonary TB, contact rate, and annual risk for infection by country to extrapolate numbers of cases and deaths prevented in children in the 5 years after vaccination. They calculated illness and deaths prevented by geographic region using estimates of BCG efficacy (73% against tuberculous meningitis and 77% against miliary TB) from the published literature and a cost estimate of $2-$3 per BCG dose (Journal Watch Infectious Diseases, 2006).
Communicable Diseases Section, Victorian Government Department of Human Services, 2005. The Blue Book: Guidelines for Control and Infectious Diseases. Victoria, Melbourne: Communicable Diseases Section, Public Health Group.
Kaufmann, S.HE., & Helmut, H. (2003). Mycobacteria and TB. Basel, Switzerland: S. Karger AG.
Palomino, J.C., Leao, S.C., & Ritacco, V. (Eds.). (2007). Tuberculosis 2007: From Basic Science to Patient Care. BourcillierKamps.