Davies (1998) opined that many things affect the way our bodies fight the tubercle bacillus. These include;
- Age and Sex: There are little differences between boys and girls up to puberty. Infants and young children of both sexes have weak defences. Up to age.
- Infection is particularly liable to result in the most fatal forms, miliary tuberculosis and tuberculosis meningitis, due to blood stream spread.
In Europe and North America, when tuberculosis was common, the peak incidence of pulmonary tuberculosis was usually in young adults. The male rate of infection continued fairly high at all ages but the female rate tends to drop rapidly after the child bearing years. Women often develop pulmonary tuberculosis following childbirth. Limited infection from Africa and India seems indicate some different pattern. The prevalence of pulmonary tuberculosis seems to increase with age in both sexes. In women the overall prevalence is lower and the rise with the ageless steep in men. In women it reaches a maximum at age 40-50 and then falls. In men it goes on rising at least to age 60.
- Nutrition: There is very good evidence that starvation or malnutrition reduces resistance to the disease. This is an important factor in poorer communities, both in adults and children.
- Toxic Factors: Tobacco, smoking and high alcohol intakes are important in reducing body defence so are corticosteroid drugs and other immunosuppressant used for treating certain disease.
- Poverty: This leads to bad and overcrowded housing or poor work condition; these may lower defences as well as making infection more likely. People living in this condition are also badly nourished. The whole complex of poverty makes it easier for the TB to cause disease.
- Race: It is difficult to separate the possible effect of race from other factors such as poverty. However there is good evidence that isolated populations, for instance Eskimos or native Americans, when they met the disease for the first time had poor defences. The disease spread rapidly and caused high mortality.
- HIV/AIDS: Reduces body defences to infection and diseases.
References
Davis, P. (1998). Clinical Tuberculosis (2nd ed.). London; Chapman and Hall Medical.
