A review on antibiotic resistance: Origin and mechanisms of bacterial resistance as biological phenomenon

Antimicrobial resistance is a natural biological phenomenon in their struggle for existence and represents a major health care issue, associated with high mortality and morbidity. The first cases of mass emergence of resistant strains were observed in the middle of the 20th century, and since then cases of resistance have been reported all over the world, and in the last two decades even more frequently are reported multiple bacterial resistance. Factors that contribute to the development of bacteria resistance are abuse in the use of antibacterial agents, in humans or livestock, and releases of antibacterial agents into the environment. Moreover, the development of new effective antibiotics is decreasing, contrary to increasing the overall effort for the synthesis of new ones. Identification and reporting of bacterial resistance, as well as monitoring of the use of antibiotics in the outpatient and inpatient setting, today is the obligation of all countries.