Cigarette smoke can influence infection and inflammation is several ways: (1) enhanced susceptibility to respiratory virus infection and subsequent enhanced colonization by potential bacterial pathogens; (2) increase in the numbers and species of respiratory bacteria due to enhanced “stickiness” of epithelial cells coated with smoke components (66); (3) enhanced pro-inflammatory responses to bacterial antigens (50); (4) reduction in anti-inflammatory IL-10 responses (37). Here, IL10 is linked to infection.