MRSA Superbug first developed antibiotic resistance to methicillin in hedgehogs 200 years ago

Antibiotics have saved countless lives over the past century. But they also put us in an evolutionary arms race with harmful bacteria. As more and more antibiotics are used to treat bacterial infections, the bacteria themselves face more pressure to mutate into strains that can become resistant to these antibiotics. Humans went back to the drawing board and developed stronger antibiotics, bacteria developed resistance to those antibiotics, etc.

At least, that’s the common understanding of how antibiotic resistance develops. But one New research published in nature on Wednesday painted a more complex picture, showing that methicillin resistance Staphylococcus aureus (also known as transcendental MRSA) developed naturally 200 years ago — long before methicillin was introduced as a clinical antibiotic.

And the MRSA culprit might surprise you: hedgehogs. Behind those adorable faces and beneath that spiky exterior, hedgehogs are essentially MRSA factories.

Methicillin was the first discovered as an antibiotic in 1959. The first reports of MRSA appeared in 1961 in the UK. It normally takes bacteria decades to become resistant to a common antibiotic, so scientists have always wondered why it took less than two years for MRSA to emerge after methicillin was first introduced. introduced. general population.

Meanwhile, people have known about the hedgehog body for some time susceptible to fungal diseases. Over the past decade, there has been a flurry of new research (led by Danish researcher Sophie Rasmussen) which shows that Nordic porcupines carry both Staphylococcus aureus and a fungus called Trichophyton erinacei on their body. Fungi make their own antibiotics to kill bacteria, but some S. aureus strains were able to develop a natural resistance to those antifungal antibiotics.

Jesper Larsen, a researcher at the State Serum Institute in Copenhagen and lead author of the new study, told The Daily Beast: “This has completely changed my perspective on how MRSA and resistance are viewed. antibiotic. “It means that there must be some selective pressure in porcupines that causes them to carry MRSA.”

Through nose and skin swabs from hundreds of hedgehogs sourced from wildlife shelters, the new study found that hedgehos across Europe and New Zealand carry a high strain of MRSA. Is called mecC– MRSA. Larsen and his team specifically found that up to 60% of wild hedgehogs in Denmark and Sweden carry mecC.

Furthermore, using gene sequencing techniques that can help with the dating of MRSA-specific mutations, the team was able to determine that mecC first appeared on porcupines two centuries ago — before methicillin was first used to treat humans and livestock.

Ultimately, the authors believe that hedgehogs started out as the first reservoir of MRSA, and this explains why MRSA spread so quickly to livestock and later humans even when methicillin was just introduced.

To be clear, the authors do not underestimate the role of clinical antibiotics in promoting MRSA growth, leading to more 80,000 cases and 11,000 deaths in the US each year. While the World Health Organization classify MRSA is one of 12 “priority pathogens that threaten human health”), only 1 in 200 cases of MRSA infections in humans causes mecC stress, overload. It must have evolved further to be better adapted to humans, although porcupine lines are a fertile starting point.

Larsen cautions that there should be no fear that hedgehogs – domestic or wild – will suddenly infect all of us with MRSA. “Clearly, we’ve been living with this problem in porcupines for 200 years, even before we had antibiotics,” he said. “So no, it’s not a big deal.”

But what the study does, Larsen says, is provide new insight into understanding the current antibiotic crisis. Random mutations can appear all the time, but they only last when there is pressure to hold them. In this case, porcupines appear to be the source of the MRSA genes, but these antibiotics in humans have helped maintain those genes in some areas. S. aureus strains.

Larsen and his team wanted to know if other interactions between antibiotic-producing fungi and bacteria were occurring in other host animals. There is little hope that these studies could lead to a breakthrough in the development of a silver bullet solution for MRSA and other superbugs — the solution to permanently ending the evolutionary arms race.