Hedgehogs Reveal Nature’s Ability to Develop Drug-Resistant Bacteria

By Mark Miller

Methicillin-resistant Staphylococcus aureus (MRSA) is an antibiotic-resistant bacteria that causes infections responsible for thousands of deaths each year. Scientists and medical professionals have long attributed such infections’ drug resistance to their ability to adapt to and “outsmart” antibiotic treatments that were first mass produced in the 1940s.

Their thinking, in other words, is that these drug-resistant strains only came about after humans introduced antibiotics. But the recent discovery of MRSA in hedgehogs may be changing that thinking.

According to a report in Science News, Sophie Rasmussen, a researcher at the University of Oxford, examined a group of hedgehogs and found that 61 percent of the animals carried MRSA.

This discovery led to further investigation and the finding that MRSA was present in hedgehogs in the United Kingdom, Scandinavia, and the Czech Republic. Researchers then analyzed the genomes, or genetic instruction manuals, of the MRSA strains and determined that their lineages appeared between 130 and 200 years ago — meaning that long before antibiotics, hedgehogs had evolved a natural way to resist the bacteria. But how?

Part of the answer was found in Trichophyton erinacei, a fungus that causes “hedgehog ringworm” in humans. A study from the 1960s revealed that this fungus found on hedgehog skin was able to kill some S. aureus, and researchers identified two penicillin-like antibiotics produced by the fungi.

The fungi “live in a bad neighborhood,” said Gerry Wright, a biochemist involved in the research. He went on to explain that they compete with other microbes such as S. aureus to colonize the host hedgehogs. "They have to work out this arrangement where they can protect themselves.”

Wright believes that antibiotic resistance comes about gradually as it is influenced by natural selection. In fact, it’s reported that his work shows that resistance has ancient origins in places that have not been influenced by humans.

In this way, the hedgehogs may show a different path forward for antibiotic-resistance research. There has been a lot of work done in the soil microbial community as well as with human microbiomes. Animal microbiomes may now provide another source to help scientists create effective treatments for drug-resistant bacteria infections like MRSA.