Ganciclovir/Valganciclovir for Prevention of CMV Reactivation in Acute Injury of the Lung and Respiratory Failure

To evaluate whether administration of ganciclovir reduces serum IL-6 levels (i.e. reduction between baseline and 14 days post-randomization) in immunocompetent adults with severe sepsis or trauma associated respiratory failure. Primary Hypotheses: \- In CMV seropositive adults with severe sepsis or trauma , pulmonary and systemic CMV reactivation amplifies and perpetuates both lung and systemic inflammation mediated through specific cytokines, and contributes to pulmonary injury and multiorgan system failure, AND \- Prevention of CMV reactivation with ganciclovir decreases pulmonary and systemic inflammatory cytokines that are important in the pathogenesis of sepsis and trauma related complications.