Antimicrobial resistance - Impact on humans

Microbes are microscopic organisms that include bacteria, viruses, fungi, protozoa, and helminths. Microbes can have positive or negative effects on human health and well-being. Bacteria normally maintain gut health which is essential for mucosal immunity and health in other organs, although they can cause a myriad of diseases ranging from bloody diarrhea to meningitis. Fungal infections, while rarer relative to bacteria, are common in immunocompromised patients. Fungal infections can be topical or systemic, ranging from rashes to more severe conditions like pneumonia and meningitis. Viruses, which are submicroscopic entities, can cause various diseases, from the common cold to influenza to rabies. These microbes cause significant morbidity and mortality around the globe; for example, the recent COVID-19 pandemic. While antibiotics, antifungals, and antivirals are used to combat these microbes, increasing reliance on these drugs leads to drug resistance. Antimicrobial resistance is one of the more serious public health concerns today and poses a threat to human wellness on a global scale. If left uncontrolled, antimicrobial resistance could be a significant healthcare problem. Additionally, antimicrobial resistance increases treatment complexity and is a growing issue in clinical settings, which presents a significant challenge to the current recommendations for managing antibiotic resistance. Medicinal chemists and pharmaceutical industries need to focus on developing new drugs that will be efficacious while minimizing drug-drug toxicity and adverse drug reactions. Physicians and other health care providers need to stay on alert for indiscriminate overuse of antimicrobials that can give rise to drug resistance; therefore, need to innovate ways of treating infections. A thorough understanding of the mechanism of evolution of antimicrobial resistance is important because it helps healthcare professionals to prevent the spread of antibiotic-resistant bacteria. By understanding the mechanisms of antimicrobial resistance, strategies can be developed to prevent the spread of resistant organisms. New antibiotics can also be synthesized or developed to treat resistant microbes. Additionally, understanding the mechanisms of antimicrobial resistance helps us identify associated risk factors, which can help develop targeted interventions to reduce the risk of antibiotic-resistant infections. This chapter will discuss various antimicrobial classes and the mechanism of drug resistance that impacts human health.