Bacterial resistance to antimicrobials is an increasing problem. Doctors occasionally face genuine therapeutic dead-ends, when attempting to cure nosocomial infections and, more and more frequently, community-acquired infections. Mastering antimicrobial resistance diffusion is nowadays a major Public Health issue.

Struggling against bacterial resistance to antimicrobials lays on three main measures:

• individual and collective hygiene.
• proper antibiotics practices, which could help reduce antibiotic selective pressure.
• better understanding of bacterial resistance mechanisms and resistance gene transfer between bacteria.

Integrons, gene capture and expression systems, are recognised as major players in resistance gene transfer, which accounts for the greater part of resistance emergence and dissemination. Integrons are typically described in Gram negative bacteria, isolated in man, environmental settings and animals. They encode resistances to nearly every class of antimicrobials. A strong link between integrons and resistance to multiple antibiotic compounds has been described and integron detection is a relevant indicator of resistance to multiple antibiotics.

The investigators project offers to study the impact of antibiotics on the frequency of integron intestinal carriage in the Limousin region and the genetic communities between the two groups.

This study will use an innovative real-time PCR technique to detect integrons directly in the sample without using traditional culture-based techniques. The investigators hope to detect new integron-carriers, notably patients for whom integrons are borne by non or poorly cultivable bacteria. Stool samples will be taken from two groups of subjects : 246 intensive-care unit patients under high antibiotic selective pressure, compared with 246 healthy individuals representative of the community, under a more usual selective pressure. In both groups, antibiotic consumption will be fully documented.

Inclusion Criteria:

• adults > 18 years
• patients Hospitalized in intensive care unit for at least 48 hours, including one antibiotic was found at least in the background (<3 months).
• patients followed by the Department for Work and Health for bacteriological examination of stool
• possible information about antibiotic therapy provided

people working in the hospital kitchen