Antibiotic resistance is selected primarily in our patients.

The potential for bacterial resistance probably existed prior to the arrival of humans on earth and bacterial populations isolated before the antibiotic era surely contained antibiotic-resistant organisms. Antibiotic resistance has undergone an explosive development following the introduction of antibiotics in medical practice and in agriculture, and there is no doubt that the higher prevalence of bacterial resistance is closely related to human activities. Strict infection control policies limit the risk of patient-to-patient transmission of resistant as well as susceptible bacteria.