Several lines of evidence suggest that alcohol consumption exerts a dose-dependent impact on the host response to infection. Chronic alcohol abuse leads to increased susceptibility to bacterial and viral infections, most notably a 3 to 7-fold increase in susceptibility (Schmidt and De Lint 1972) and severity (Saitz, Ghali et al. 1997) of bacterial pneumonia compared with control subjects. Similarly, the incidence of Mycobacterium tuberculosis infection among alcoholics is increased (Sabot and Vendrame 1969, Hudolin 1975, Kline, Hedemark et al. 1995, Panic and Panic 2001). Alcohol use has also been shown to drive disease progression in chronic viral infections such as human immunodeficiency virus (HIV) (Baum, Rafie et al. 2010) and Hepatitis C (Bhattacharya and Shuhart 2003). In addition, the magnitude of antibody response following vaccination with Hepatitis B is lower in alcoholics compared to controls (Nalpas, Thepot et al. 1993).
