Ethanol Consumption and the Susceptibility of Mice to Listeria monocytogenes Infection

Abstract

It is well known that excessive alcohol consumption correlates with increased infectious disease. However, the molecular microbiological and immunological bases for ethanol-induced alterations in host defense are largely unknown. To study the effect of alcohol consumption on the pathogenesis of intracellular bacteria, we examined the relative susceptibility of alcohol-fed mice to a virulent strain of Listeria monocytogenes. Based on lethal dose 50% determinations, survival curve analysis, and bacterial burden, alcohol consumption did not increase the susceptibility of C57BL/6, BALB/c, or A/J mice to systemic infection by strain EGD. Mice fed an ethanol-containing liquid diet showed slightly reduced susceptibility to Listeria. Alcohol consumption modestly decreased bacterial numbers in the spleen but not the liver. We also found that mice fed a typical solid diet were more sensitive to EGD infection than were animals fed a control liquid-containing diet. This study indicates that alcohol consumption may not always increase infectious disease progression.