Why you can't take antibiotics without prescription: a microbiologist's opinion

The number of infections caused by antibiotic-resistant bacteria is skyrocketing. According to the U.S. Centers for Disease Control and Prevention (CDC), cases of infections with the NDM-CRE strain - so-called "nightmare bacteria" - have increased by 70% from 2019 to 2023. These microorganisms are nearly untreatable and often fatal.

Brenda Wilson, Professor of Microbiology at the University of Illinois at Urbana-Bampaign and author of Revenge of the Microbes: How Bacterial Resistance is Destroying the Miracle of Antibiotics, explained how resistance forms and why the world is facing a new "antibiotic resistance epidemic".

How bacteria become invulnerable

Antibiotics kill most bacteria, but in every population there is initially a part of microorganisms that have innate or acquired resistance. After a course of treatment, it is they who survive, multiply and form a new generation, no longer insensitive to the drugs.

"The trouble is that resistance genes can be transferred between different species of bacteria. One species can 'share' them with another - and eventually a common infection becomes untreatable," Wilson explains.

These genes are often passed on through plasmids - fragments of DNA that act as information carriers. Therefore, a single bacterium can quickly become resistant to several types of antibiotics at once.

The Institute for Health Metrics Evaluation (IHME) estimates that more than 1 million people will die from infections caused by antibiotic-resistant bacteria in 2021. By 2050, the number of deaths is projected to rise to 8-10 million per year, and economic losses could reach $100 trillion.

The CDC identifies 18 of the most dangerous antibiotic-resistant pathogens. Six of them cost the U.S. health care system about $5 billion annually.

Treating these infections requires the use of "second" or "third line" drugs - they are less effective, toxic and expensive. Patients with resistant infections are more likely to end up in the ICU, stay in the hospital longer, and often die from complications.

What are "nightmare bacteria"

NDM-CRE strains belong to the Enterobacterales family and contain the New Delhi metallo-β-lactamase (NDM) gene that makes them resistant to carbapenems, the "last hope" antibiotics.

"These bacteria are already resistant to many drugs, and having the NDM gene makes them virtually invulnerable to all known antibiotics," says Wilson.

The mortality rate for these infections is as high as 40-50 per cent because doctors often fail to find effective treatment in time. The CDC is urging healthcare providers to increase surveillance, limit antibiotic prescribing, and expand patient testing.

In addition to NDM-CRE, experts are tracking strains of Klebsiella and E. coli resistant to carbapenems, as well as Mycobacterium tuberculosis and Acinetobacter baumannii, which are already virtually unresponsive to therapy.

Of particular concern is the fungus Candida auris - more than 1,000 cases of infection with this resistant pathogen have been reported in Illinois in recent years.

What to do to stop the rise of antibiotic resistance

Fighting antibiotic resistance requires not only new drugs, but also the smart use of existing ones, Wilson says. Among the main measures:

• avoiding uncontrolled prescribing of antibiotics;

• reducing their use in agriculture;

• control of water and soil contamination with antibiotic waste;

• improving hygiene, vaccination and sanitation standards.

"Antibiotics are not a panacea, but a tool that must be used responsibly. Otherwise we risk returning to an era when a simple infection could be fatal," warns Professor Wilson.