Introduction to the themed collection on antimicrobial resistance

The battle between humankind and invading infections/pathogenic microorganisms has been an ever-growing and constant one. Infections by bacteria, fungi, viruses, and parasites have shaped human history through millennia. In this backdrop, the discovery of antimicrobial agents was a game-changer event. Antibiotics, antivirals, antifungals, and antiparasitic agents are examples of antimicrobials, which are drugs used to prevent and treat infections. This watershed therapy, however, seems to be on the verge of being completely undone by the emergence of antimicrobial resistance (AMR) that has been becoming increasingly prevalent in recent years. AMR is not a new or recent concept. Rather, it succeeded the discovery of antibiotics by a few years. However, its devastating effects started showing around a few decades ago, when clinics were faced with infections caused by microbial superbugs, which were resistant to a variety of antimicrobial agents. The term “superbugs” is occasionally used to describe microorganisms that develop AMR. Today, AMR has emerged as one of the most pressing global health challenges of our time. The World Health Organization (WHO) has declared AMR a global health emergency, warning that if left unchecked, it could lead to millions of deaths annually by 2050.

The current scenario of AMR deserves a thorough relook, with a view to understanding and overcoming this healthcare crisis. Higher resistance towards commonly used antibiotics, particularly for infections such as urinary tract infections, sexually transmitted infections, sepsis, and some types of digestive system infections, have been reported globally, indicating that we are soon facing an eminent lack of effective antibiotics. The sustainable development goals (SDG) monitoring framework now includes a new AMR indicator for 2019. Methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli resistant to third generation cephalosporins are the two specific drug-resistant bacteria that this indicator tracks. The global tuberculosis epidemic is being threatened by new antimicrobial resistant Mycobacterium tuberculosis strains. According to WHO estimates, there were over 500 000 new cases of rifampicin-resistant tuberculosis (RR-TB) reported globally in 2018. Many of these cases were multidrug-resistant tuberculosis (MDR-TB), a type of the disease that is resistant to the two most potent anti-TB medications.

Antiviral drug resistance is a growing concern in populations of immunocompromised patients because persistent viral replication and extended drug exposure select resistant types of viruses. The majority of antivirals, including antiretroviral (ARV) medications, have developed resistance. Due to the advent of HIVDR, all ARV medications, even newer classes, run the risk of losing some or all of their effectiveness. One of the biggest dangers to controlling malaria is the evolution of drug-resistant parasites, which increases malaria morbidity and mortality. The tested artemisinin-based combination therapies (ACTs) continue to be quite effective. However, increased resistance to artemisinin and the ACT companion medications could endanger significant advancements in malaria control and could present a serious public health concern.

Drug-resistant fungal infections are becoming more common, which makes the already challenging treatment environment worse. There are now problems with treating many fungi, such as toxicity, especially in people with additional underlying illnesses (such as HIV). One of the most prevalent invasive fungal diseases, drug-resistant Candida auris, is already pervasive, with rising reports of resistance to antifungal azoles, polyenes, as well as elevation in echinocandin resistance. This results in fungal infections that are more challenging to treat, treatment failures, lengthier hospital stays, and significantly more expensive treatment alternatives.

Antimicrobial resistance is a complex problem that requires a multifaceted approach. While the development of new antimicrobial agents is essential, it is not enough on its own. Strategies to prevent the spread of drug-resistant infections, such as infection control measures and antimicrobial stewardship programs, are also critical. In addition, research on AMR mitigation should involve scientists from multiple disciplines, such as chemistry, microbiology, pharmacology, biomaterial science, immunology, etc. Researchers must work together to identify new antibiotics, alternative therapies, and vaccines. Along with researchers, contribution from other segments of society, such as clinicians, pharmacists, and other healthcare professionals, policymakers, policy experts, and analysts, and the end-users (i.e., patients), is equally important. Such an interdisciplinary and united approach is the only way to tackle the never-ending challenge of AMR.

We hope that the readers gain important perspectives about emerging research in the field of AMR and therapy through this themed collection. The collection includes reviews and research articles. A wide readership will benefit from the multifaceted reviews and articles, covering areas such as siderophores in antibiotic design, ribosomal RNA methylation, antibiotic adjuvants to overcome antibiotic modification, among others. The collection is growing, and new articles are being added to it. We invite curious readers to visit and revisit the collection regularly and enjoy the plethora of articles and reviews. We also hope that this collection will serve as a melting pot of various themes covered under AMR and antimicrobial therapy.

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