The Impact on the Hospital's Microbial Ecology Follow the Introduction of Ertapenem and Other Newly Introduced Antibiotic, Using Antibiotic Utilization and Hospital Susceptibility Data Over Time

This is a retrospective, multicentre, observational study to assess the trends in antibiotic utilization and hospital ecology with respect to susceptibility patterns of selected bacterial isolates to the utilized antibiotics.

There will be two sets of data collected: Hospital acquired infection (only the first pathogen cultured of each episode) and All infection (the whole hospital susceptibility data)

Primary Objectives:

1. To study the impact of the introduction of ertapenem on the susceptibility pattern of various pathogens to imipenem/meropenem.
2. To study the impact of the introduction of ertapenem on the susceptibility of all Gram negative bacilli to antimicrobial agents commonly used in the participated study sites.
3. To explore the trend in antimicrobial utilization before and after the introduction of new antimicrobial agents to the hospital formulary during the index period.

Secondary Objectives: