CRP and Salmonella Infections: Old data have revealed CRP’s protective role toward fatal Salmonella enterica serovar typhimurium infection in transgenic mice, and another study reported CRP ≥ 20 mg/L in most children with Salmonella infection and in about 17% of those with viral infection, concluding that the very good negative predictive of CRP < 20 mg/L may allow clinicians to reliably rule out Salmonella as an etiology of gastroenteritis.