GNV News, April 19, 2026

Bacteria cause infectious diseases, and humans cure them by administering antibiotics that kill the bacteria. However, bacteria evolve quickly, and sometimes drug-resistant strains (so-called “superbugs”) that are resistant to antibiotics emerge and multiply. The number of such antibiotic-resistant infections has been confirmed to be increasing worldwide, becoming a serious public health problem. Traditionally, it was thought that drug-resistant bacteria were increasing due to factors such as excessive prescription of antibiotics, but a study published on March 23, 2026 pointed to a new factor: drought.

There are many soil microorganisms living in the soil, competing for the water and nutrients they need to survive. Some soil microorganisms synthesize and secrete natural antibiotics in order to eliminate other bacteria under competitive conditions. At the same time, among soil microorganisms there are also bacteria that possess resistance genes needed to survive attacks from those antibiotics. When drought reduces the amount of moisture in the soil, soil microorganisms become densely packed into the limited wet spaces, nutrients become scarce, and competition intensifies. As a result, bacteria produce more antibiotics to attack one another, and new resistance genes may emerge, or bacteria that already possess resistance genes may find it easier to survive, leading to an accumulation of resistance genes.

Why, then, do the resistance genes that increase in the soil lead to infectious diseases in humans? The key is a process called “horizontal transfer,” in which bacteria exchange genes with each other. Resistance genes that increase under the intense competition brought about by drought can potentially be taken up by bacteria that infect humans above ground. In fact, there are reports that common resistance genes have been found in both soil bacteria and pathogenic bacteria.

It has been pointed out that antibiotic resistance is not only a medical issue, but also an ecological problem that cannot be separated from climate change.

Learn more about the recent increase in drug-resistant bacteria, especially in middle- and low-income countries → “Infections with antibiotic resistance are rapidly increasing”

Learn more about antibiotics → “Is the era when antibiotics no longer work just around the corner?”

Lithia Springs, Georgia, USA, struck by drought (Photo: Global Water Partnership – a water secure world / Flickr [CC BY-NC-SA 2.0])