M.
tuberculosis infects
about one third of world population and kills about three Million patients each
year. Therefore it is the single most important infectious cause of death (D.R.
Arora 2004 P. 85).
Tuberculosis is a world wide disease. The problem
of tuberculosis is acute in the developing countries which accounts for about
95% of tuberculosis cases with South East Asia Region, Western pacific and Africa worst affected region (K. Park 2009).
|
Africa 20%
|
|
Europe10%
|
|
East meditariarian
4%
South East Asia Region 38%
Western pacific 22%
America 6%
|
Estimated
new tuberculosis cases by region (WHO 2000).
With alleviation of
overcrowding and introduction of effective antibiotics in the 1950s, the rate
of m. tuberculosis infections and
deaths declined in the developing countries. But since mid 1980s, tuberculosis
has been increasing in these countries especially in Africa. This is partly
because m. tuberculosis infects
persons with AIDs who have a diminished T. cell mediated resistance to m. tuberculosis. According to WHO
estimate, about 1, 000 million individuals are infected annually, 10-20 million
develop overt disease, 4-5 million become open or infectious cases and around 3
million die.
Nigeria is 4th amongst 22 countries with high tuberculosis
burden. Estimated new cases of tuberculosis of all forms per year is
290/100,000 with estimated prevalence of 531/100,000, The mortality ratio is
82/100,000 per year
(Dr. Girdado M. 2003).