PTGS2 and infection: The nonselective COX-1/2 inhibitor indomethacin and the selective COX-2 inhibitor NS-398 both inhibited PSaV-mediated PGE2 production in a dose-dependent manner when added either immediately after the removal of the virus inoculum (posttreatment) or during the entire course of the infection (pre/posttreatment) (Fig. 2A and B).