CRP and viral infectious disease: Moreover, when CRP was applied in a rule-in/rule-out strategy, whereby below 20mg/l classifies as viral infection and above 80mg/l classifies as bacterial infection, the sensitivity was the same as BV (100.0%), but CRP's specificity was lower (74.5% vs. 89.5%, respectively) and the equivocal rate was 2.7-fold higher.