Can smoking cause infection?

Smoking increases the risk of infection and the epidemiology of smoking related infection, and delineated implications of this increased risk of infection among cigarette smokers. Cigarette smoking is a substantial risk factor for important bacterial and viral infections. For example, smokers incur a 2 to 4 fold increased risk of invasive pneumatically disease. Influenza risk is several fold higher and is much more severe in smokers than nonsmokers. Perhaps the greatest public health impact of smoking on infection is the increased risk of tuberculosis, a particular problem in underdeveloped countries where smoking rates are increasing rapidly.