Discovery of MRSA-busting antibiotic gives hope against resistant superbugs
Discovery gives hope against resistant superbugs
Last year, England’s chief medical officer, Dame Sally Davies, warned that antibiotic resistance could spell “the end of modern medicine”, with routine operations becoming impossible because doctors run out of antibiotics to keep common infections at bay.
The discovery of a new class of antibiotics that can wipe out persistent infections of the hospital superbug MRSA has raised fresh hopes for progress in the fight against antimicrobial resistance.
In the latest research, US scientists focused on a small but important group of recurrent infections, which are driven by bacteria that evade antibiotics by lying dormant in the body.
The lead scientist on the study, Eleftherios Mylonakis, whose mother died from a drug-resistant hospital infection, said the drug was some years away from human trials, but added: “The hope is that we are a step closer to finding a treatment for the most difficult bacteria.
The MRSA persisters are resistant to antibiotics and MRSA is both common and very virulent.” The rise of drug-resistant infections is a direct consequence of evolution.
To combat the spread of antibiotic resistance, doctors and farmers have been urged to use antibiotics far more sparingly than in the past, but this week a separate research team revealed that antibiotic use worldwide has increased by more than 65% since 2000.
When people or animals are given antibiotics, some of the bacteria the drugs are meant to kill may survive because they have chance mutations that protect them.
Health officials around the world have seen a steady rise in bacterial infections that no longer respond to routine antibiotics.
The drugs were not effective against an entire group of harmful bacteria for which new antibiotics are badly needed.
However, the drugs still hold promise for treating persistent MRSA infections that can be lethal for patients affected.
Responsible for urinary tract infections, stomach bugs, gonorrhoea, pneumonia and the plague, among other diseases, these include Escherichia coli, Pseudomonas aeruginosa, Neisseria gonorrhoeae, Klebsiella pneumoniae and Yersinia pestis.
Over many microbial generations, these mutations become more dominant and the bacteria more resistant, meaning new drugs are needed to wipe them out.
With resistance emerging faster than new drugs can be developed, the World Health Organisation (WHO) has called for urgent action to combat the problem.
Led by a team at Rhode Island Hospital in Providence, the scientists tested the effects of 82,000 lab-made molecules on roundworms infected with MRSA, or methicillin-resistant Staphylococcus aureus.
Writing in the journal Nature, the scientists describe how they tweaked one of the retinoid compounds to make it less toxic, and then injected it into a mouse with what would generally be considered to be a treatment-resistant MRSA infection.
Tests on the two retinoids, combined with computer modelling, showed that the compounds killed not only normal MRSA cells, but dormant, or “persister”, cells too.