Studies suggest a superbug MRSA that evolved in hedgehogs long before clinical use of antibiotics

An international team of scientists, led by researchers at the University of Cambridge, have found evidence of a type of methicillin resistance, a superbug of antibiotic resistance. Staphylococcus aureus (MRSA) occurred in nature 200 years ago, long before antibiotics were used in humans and livestock. It has traditionally been criticized for its appearance. A newly reported study based on hedgehog findings tracked the genetic history of the bacterium.Researchers say that antibiotic resistance Staphylococcus aureus Lives in the skin of a hedgehog that also carried fungi Trichophyton erinacei, Produces its own antibiotics. In effect, hedgehogs carry fungi and bacteria to their skin, and the two are trapped in a battle for survival.

Dr. Mark Holmes, a researcher at the University of Cambridge Veterinary School, said: “There is a very large wildlife” reservoir “where antibiotic-resistant bacteria can survive. From there, it’s a short step to be picked up by livestock and infect humans. “

Holmes is the co-lead author of a paper published by the team. Nature,title,”The emergence of methicillin resistance precedes clinical use of antibiotics“These results take a broader view of One Health on the role of natural selection in wildlife and antibiotic resistance, which recognizes the connectivity of nature, agriculture, and human ecosystems in evolution and spread. It emphasizes the importance of this. Of antibiotic-resistant pathogens. ”This study was conducted by a large international collaboration involving researchers from the University of Cambridge, the Welcome Sanger Institute, the Serum State Institute in Denmark, and the Royal Botanical Gardens of Kew. it was done.

The authors write that the discovery of antibiotics over 80 years ago has significantly improved the health of both humans and animals. “Although antibiotic resistance to environmental bacteria has been around for a long time, resistance to human pathogens is believed to be a modern phenomenon caused by clinical use of antibiotics.” Antibiotic misuse is now accelerating the process. Antibiotic resistance has risen to dangerously high levels in all parts of the world. “MRSA is one of the most common antibiotic-resistant bacterial pathogens, causing about 171,000 invasive infections each year in Europe alone,” the team added. “MRSA was first identified in 1960, shortly after the introduction of methicillin (cerbenin) as a treatment option for penicillin resistance. Staphylococcus aureus Although it is a clone, it may have been selected by clinical use of penicillin over the last 20 years. “

Methicillin resistance is now found in many people Staphylococcus aureus All over the world, hospitals, communities, livestock clones. “This has serious implications for the treatment of severe infections, and the World Health Organization now considers MRSA to be a significant threat to human health,” the researchers further commented.

Methicillin resistance Staphylococcus aureuss is mediated by the antibiotic resistance gene (ARG) mecA When mecC.. The work led by Holmes was first identified in 2011 mecC-MRSA in human and dairy cow populations. At that time, it was thought that the strains developed in cattle because large amounts of antibiotics were routinely administered to these livestock.Causes about 1/200 of all MRSA infections mecC-MRSA. MRSA is much more difficult to treat than other bacterial infections because it is resistant to antibiotics. MRSA is not only a major threat to human health, but also a major challenge in livestock.

Holmes and colleagues supported a newly reported study to investigate the surprising findings of up to 60% of hedgehogs from the Danish and Swedish hedgehog surveys. mecC-MRSA. “A Danish and Swedish hedgehog survey showed a surprisingly high prevalence of MRSA infections. mecC ((((mecC-MRSA), in contrast to the clinical use of antibiotics, increases the likelihood that the evolution of these bacteria was caused by natural selection of wildlife. ” A new study also found that swabs taken from hedgehogs throughout Europe and New Zealand contained high levels of MRSA.

Researchers say that antibiotic resistance Staphylococcus aureus As an adaptation to the fact that it must be present alongside fungi on the skin of hedgehogs Trichophyton erinacei.. “Our hypothesis is mecC-MRSA is driven by natural selection and is supported by studies in Northwestern Europe and New Zealand showing that hedgehogs frequently colonize dermatophytes. T. hedgehog, Produces a penicillin-like substance that is unstable to penicillinase, recently identified as penicillin G, “they said.

To test their hypothesis, researchers mecC-MRSA and others Staphylococcus aureus Hedgehog isolates from 10 European countries and New Zealand. “Sequenced 244 Staphylococcus aureus Isolate 913 Staphylococcus aureus from hedgehogs and other sources to speculate on major evolutionary history, host dynamics, geographical dispersal patterns, and zoonotic diseases. mecC-European MRSA clones, “they explained.

“Using sequencing technology, mecC-MRSA’s antibiotic resistance dates back to its first appearance and was found to have existed around the 19th century, “said Dr. Ewan Harrison, a researcher and lead author at the Welcome Sanger Institute and the University of Cambridge. I am saying. ..

He added: “Our study suggests that it was not the use of penicillin that promoted the first appearance of MRSA, but a natural biological process. MRSA for survival in the skin of Hari rats. We believe that it evolved in battle and then spread to livestock and humans through direct contact. “

Researchers say that resistance to them is likely to already exist in nature, as almost all of the antibiotics we use today originate in nature. Overuse of antibiotics in humans and livestock will benefit resistant insects. Therefore, it is only a matter of time before antibiotics begin to lose their effectiveness. As the author commented mecC-MRSA isolates are probably from a local hedgehog reservoir, mecC-MRSA was probably the cause of sporadic human infections in the last 200 years, more than a century before MRSA was first identified in patients in 1960 … probably due to host interactions leading to zunotic infections. Includes direct contact with hedgehogs or contact with secondary infections As previously shown, animal hosts such as dairy cows T. erinacei (Cause of human “ringworm”). “

Researchers believe that findings are not a reason to fear hedgehogs, as humans are rarely infected. mecC-MRSA has been in hedgehogs for over 200 years. “Hedgehog isn’t the only place where antibiotic-resistant bacteria live. All wildlife has different types of bacteria, not just parasites, fungi, and viruses,” Holmes said. increase. “Wildlife, livestock, and humans are all interrelated. We all share one ecosystem. We cannot understand the evolution of antibiotic resistance without looking at the entire system.”

As the researchers further commented, “It is reasonable to assume that wildlife microbiota are more exposed to environmental resistomes than human microbiota and are therefore more likely to acquire environmental ARG. It seems. Therefore, wildlife may represent previously unrecognized conduits that can transfer environmental ARGs to clinical pathogens. “

Recognizing some restrictions on the reported studies, the authors conclude: Staphylococcus aureus For colonization of hedgehogs infected with dermatophytes. The evolution of clinically relevant antibiotic resistance genes in wildlife and the connectivity of natural, agricultural, and human ecosystems makes the use of a “one health” approach important for understanding and managing maximum antibiotic resistance. Shows that it is a threat to global health, food security and development. “