Selenium deficiency increases the pathology of an influenza virus infection

Selenium (Se) deficiency has previously been shown to induce myocarditis in mice infected with a benign strain of coxsackievirus. To determine if Se deficiency would also intensify an infection with influenza virus, Se-deficient and Se-adequate mice were infected with a mild strain of influenza, influenza A/Bangkok/1/79 (H3N2). Infected Se-deficient mice developed much more severe interstitial pneumonitis than did Se-adequate mice. This increase in pathology was associated with significant alterations in mRNA levels for cytokines and chemokines involved in pro-inflammatory responses. These results demonstrate that adequate nutrition is required for protection against viral infection and suggest that nutritional deprivation may be one of many factors that increase the susceptibility of individuals to influenza infection.