In the present study, 41.7% of cases were early-onset VAP, which is similar to other studies reporting early-onset VAP in almost half of all VAP episodes [3,22]. It was observed that majority of the VAP episodes occurred within the first two weeks of MV. The interaction of several risk factors during the initial days of MV put the patient at higher risk and also the exhaustion of most vulnerable patients during the first few weeks leads to the decline in the occurrence of VAP in later days [23].