An overview of antimicrobial resistance and its mechanisms

Antimicrobial agents are key components in the treatment of bacterial and viral infections, as antimicrobial resistance (AMR) has been a challenge since antibiotics were discovered. It was previously known that bacteria could develop resistance against certain drugs, and it soon became apparent that pathogenic microorganisms develop resistance to various types of antimicrobial drugs. Today, resistance to antimicrobials is a leading source of morbidity and mortality globally. Antimicrobial agents fight against bacteria by preventing their growth and spread and can be classified as either bactericidal or bacteriostatic agents. Antibiotics are also categorized into different classes and can be used to treat different targets. AMR is a type of drug resistance that occurs due to various factors such as drug modifications and active efflux. Understanding the various mechanisms involved in the development of AMR can help in developing effective treatments for different diseases caused by microbes. This chapter will focus on the mechanisms by which microbes develop resistance to antimicrobial agents and the methods of acquiring resistance in microorganisms. It will also examine current challenges in measuring the burden and prevalence of AMR.