Steven W Kerrigan
Antibiotics are one of the greatest breakthroughs in medical history. They turned once-deadly infections into treatable illnesses and made modern healthcare possible. But bacteria are changing, and some of the drugs we have depended on for decades are becoming less effective.
Around the world, infections are becoming harder to treat. This problem is known as antimicrobial resistance. It happens when bacteria evolve ways to survive medicines designed to kill them. It is estimated that drug-resistant infections already cause about 1.27 million deaths every year worldwide.
The World Health Organization has warned that we may be moving towards a “post-antibiotic era” in which common infections once again become dangerous, and even routine injuries or procedures carry serious risk.
A century ago, that was normal. A cut from gardening, a sore throat or childbirth could turn into a life-threatening infection. Doctors had few effective treatments, and infectious diseases such as pneumonia, tuberculosis and diarrhoea disease were among the leading causes of death. The arrival of antibiotics changed that dramatically.
Penicillin, discovered by Alexander Fleming in 1928, marked the beginning of one of the most important revolutions in medicine. Before antibiotics, tuberculosis was one of the world’s deadliest infectious diseases. In 1882, it killed one in seven people living in the US and Europe. Once antibiotics became available, many bacterial infections that had once been deadly could be treated effectively.
Antibiotics not only cured infections, but also made modern medicine far safer. Many procedures rely on them to prevent or treat infection, including caesarean sections, organ transplants, joint replacements and cancer chemotherapy.
Without effective antibiotics, these treatments would become much more dangerous. Fleming himself recognised that risk. When he accepted the Nobel Prize in 1945, he warned that misuse of penicillin could lead to resistance.
Living in a microbial world : The human body contains about 30 trillion human cells, but it also carries tens of trillions of bacteria on the skin and inside the body. Together, these communities form the microbiome, the vast collection of microbes that live in and on us. Many of them are not harmful. In fact, they help digest food, produce vitamins and support the immune system, the body’s defence system against disease.
So life is a finely balanced relationship between humans and the microbial world. But bacteria are ancient and extraordinarily adaptable. They have existed on earth for more than 3.5 billion years and survive in some of the harshest places imaginable, from deep-sea vents to polar ice.
Bacteria multiply very quickly and can also swap genetic material, meaning they can share useful survival traits with one another. Some produce substances that break down antibiotics before the drugs can do any damage. Others alter the parts of their cells that antibiotics are designed to attack. (Courtesy: DTE)