While COX-2 expression can be directly induced by pore-forming toxins via, e.g., calcium signalling [28], induction of mPGES might be delayed due to lower induction of pro-inflammatory mediators required for its upregulation in case of infection with the serotype 9 strain 8067 and, therefore, leading to lower PGE2 levels. The gene discussed is PTGS2; the disease is infection.