Insights into Editorial: Enter the superbug?
30 May 2016
Researchers have found a person in the United States carrying bacteria resistant to antibiotics of last resort. This has caused alarm among public health and infectious disease experts.
- The person was carrying coli bearing a new gene, mcr-1, which is resistant to even colistin, the last available antibiotic that works against strains that have acquired protection against all other medication.
What’s the main concern now?
Over the long term, experts are very worried that colistin resistance, which can spread easily to other bacteria, could lead to superbugs that could cause untreatable infections. Also, mcr-1 poses a threat of an entirely different order. In this case a small piece of DNA (plasmid) found outside the chromosome carries a gene responsible for antibiotic resistance. Since the gene is found outside the chromosome, it can spread easily among different types of bacteria, as well as among patients. The mcr-1 gene has been reported in other countries, including the United Kingdom in 2008.
The mcr-1 gene was first identified in China in November 2015, following which there were similar reports from Europe and Canada. The unchecked use of antibiotics in livestock is a major reason for the development of drug resistance. Indeed, given the widespread use of colistin in animals, the connection to the drug-resistant mcr-1 gene appears quite clear.
Also, according to a report, a significantly higher proportion of mcr-1 positive samples was found in animals compared with humans, suggesting that the mcr-1 gene had emerged in animals before spreading to humans. Besides being administered for veterinary purposes, colistin is used in agriculture.
What is a superbug?
A superbug, also called multiresistant, is a bacterium that carries several resistance genes. These are resistant to multiple antibiotics and are able to survive even after exposure to one or more antibiotics.
What causes them to mutate like that?
Like any living organism, bacteria can mutate as they multiply. Also like any living organism, bacteria have a strong evolutionary drive to survive. So, over time, a select few will mutate in particular ways that make them resistant to antibiotics. Then, when antibiotics are introduced, only the bacteria that can resist that treatment can survive to multiply further, proliferating the line of drug-resistant bugs.
Why is Antibiotic Resistance a Big Deal?
The discovery of antibiotics less than a century ago was a turning point in public health that has saved countless lives. Although antibiotic resistance develops naturally with normal bacterial mutation, humans are speeding it up by using antibiotics improperly. According to a research, now, 2 million people a year in the US develop antibiotic-resistant infections, and 23,000 of them die of those infections.
Why is the medical community worried?
Basically, superbugs are becoming more powerful and widespread than ever. Medical experts are afraid that we’re one step away from deadly, untreatable infections, since the mcr-1 E.coli is resistant to that last-resort antibiotic Colistin. Antibiotic-resistance is passed relatively easily from one bacteria to the next, since it is transmitted by way of loose genetic material that most bacteria have in common.
The World Health Organization (WHO) is afraid of a post-antibiotic world, where loads of bacteria are superbugs. Already, infections like tuberculosis, gonorrhea, and pneumonia are becoming harder to treat with typical antibiotics.
What Can We Do?
First step would be to limit antibiotic use. If a patient has a virus, for instance, an antibiotic won’t work, so doctors shouldn’t prescribe antibiotics even if the patient insists. And when patients do need antibiotics, it’s important to make sure they take the full course to kill off every last infection-causing germ. Otherwise the strong survive, mutate, and spread. As a society, curbing antibiotic use in healthy animals used in human food production is another important step.
According to few recent studies, nanotechnology holds the key to stopping antibiotic-resistant bacteria and the deadly infections they cause. Scientists have developed light-activated nanoparticles — each roughly 20,000 times smaller than the thickness of a single human hair and have shown in lab tests that these “quantum dots” are more than 90% effective at wiping out antibiotic-resistant germs like Salmonella, E. coli and Staphylococcus. With the emergence of this Colistin-resistant E.coli, the medical community is going to be working harder and faster to contain superbugs and develop new treatments for infections.
The global community needs to urgently address the indiscriminate use of antibiotics in an actionable manner, and fast-track research on the next generation of drugs.