Microbial resistance to antibiotics

Antibiotics have selective toxicity against bacteria. This is pos­sible because these drugs bind to certain protein and inhibit their activity, proteins that exist only at the level of bacteria and not at the level of the macroorganism, and on the other hand, these structures are of vital importance for the bacteria. Being of protein nature, these structures are genetically de­ter­mined. This makes an antibiotic effective only against bac­te­ria that have such genes, the other bacteria being re­sis­tant to the antibiotic. This type of bacterial resistance to antibiotics is called natural resistance. But there is also an acquired resistance of bacteria to antibiotic that refers to the fact that some bacteria were initially sensitive or even very sensitive to a particular antibiotic, but later developed re­sis­tant strains. The acquired resistance is also genetically co­ded and occurs through genetic mutations. When the re­sis­tance-encoding gene is located at the chromosome level, we talk about chro­mo­so­mal resistance, and when it is located out­side the chromosomes, extracromosomal resistance is discussed. Chromosomal resistance is transmitted only within the same bacterial strain and disappears with the dis­ap­pea­rance of that strain. Extracromosomial resistance can also be transmitted between bacteria belonging to different strains or species. Microbial resistance to antibiotics is more com­mon when the antibiotic is older and more commonly used. This makes the antibiotic resistance of microbes vary from one geographic area to another. Generally, in rural areas there are fewer strains of resistant microbes to antibiotic than in urban environments. Most resistant strains are found in the hospital environment where many antibiotics are used. There are also antibiotic resistance differences between different countries depending on how antibiotics were used in each country. The most effective way to preserve the efficacy of antibiotics in the treatment of infectious diseases is a national policy of rational use of antibiotics.