India restricts antibiotic use in light of NDM-1

The Indian Union Health Ministry announced this week that it is planning to tighten control of antibiotic use. Certain antibiotics, such as carbapenem, imipenem, and meropenem, will be put under more stringent restrictions if the new rule is passed. Other ideas under consideration are mandatory “drug control” and “infection control” committees in hospitals, where the drug control committee will oversee the use of controlled antibiotics and the infection control committee will monitor and analyze infection rates.

The proposed changes are aimed to combat the spread of NDM-1 superbug and to slow the evolution of other drug resistance bugs in the future. NDM-1 superbugs are resistant to most antibiotics; in fact, the prevalent use of antibiotics in India partially contributed to the emergence of the superbug. NDM-1 first appeared in India in August of this year and has quickly spread to other countries, including the U.S. (See our previous blog post).

Link to Article

NDM-1 found in Massachusetts

Back in August, NDM-1 bacteria made national news when it was discovered in Europe and many predicted that it will spread to the rest of the world. Yesterday, I read on Boston Globe's online portal that a case of NDM-1 had been found in Massachusetts General Hospital (MGH).

NDM-1 is a gene that makes bacteria highly resistant to many classes of antibiotics. The bacteria originated in India, where unregulated use of antibiotics is common. The MGH patient had recently traveled to India, had spent time in a hospital there, and was undergoing cancer treatment at MGH when the bug was discovered. Two other cases have also been identified in California and in Illinois.

The most worrisome aspect of this bug is the lack of antibiotics to treat it. Currently, only two antibiotics are some what effective against NDM-1 bacteria: colistin and tigecycline, and doctors don't foresee any new antibiotics being developed in the near future. To quote the author of the article, "The paucity of drugs reflects not only the strength of the superbug but also the long-neglected development of new antibiotics."

Full text of the Boston Globe article

New Technologies

We’re seeing all sorts of advances in fighting MRSA lately! AdvanSource Biomaterials Corporation recently received a patent for antimicrobial polyurethane resins, which can be used structurally or as coatings in different kinds of catheters, and are intended to help combat methicilin-resistant staphylococcus aureus (MRSA) infections.

Press release here: http://phx.corporate-ir.net/phoenix.zhtml?c=68271&p=irol-newsArticle&ID=1463328

Also, on the heels of the emergence of the NDM-1 gene, BioScience Laboratories announced that they’ve obtained seven clinical isolates of Carbapenem-Resistant (CR) Klebsiella pneumonia and Escherichia coli. BioScience Laboratories intends to use these isolates to test products for their predicted efficacy against bacteria containing the NDM-1 gene.

Press release here: http://www.24-7pressrelease.com/press-release-rss/bioscience-laboratories-announces-testing-capabilities-for-ndm1-165887.php

MRSA infections down, but new threat on the horizon

A study just published in The Journal of the American Medical Association (JAMA) shows that the incidence of hospital-onset methicillin-resistant staphylococcus aureus (MRSA) infection decreased by 28% from 2005 to 2008.  The measurements, taken from 9 major metropolitan areas across the country, also show that MRSA rates for healthcare-associated community-onset infections decreased 17% over the same time period. 

The study’s authors, Kallen et al., are unable to say why the rates decreased, but mention a couple possible factors.  The first possibility is the widespread implementation of MRSA prevention practices.  Kallen et al. note that “the fact that the observed reductions were greater among hospital-onset infections than healthcare–associated community-onset infections suggests that prevention practices in acute care settings contributed” to the decrease in MRSA infection rates.  Another potential factor is a change in the strains associated with MRSA infections, but the authors state that there weren’t changes in MRSA strain composition during that time period, so this is unlikely to be a valid explanation. 

Immediately on the heels of this good news comes a study published in The Lancet Infectious Diseases today, which details how a new bacterial gene might cause worldwide health problems.

NDM-1, which stands for New Dheli metallo-β-lactamase 1, makes bacteria highly resistant to many classes of antibiotics, including the carbapenems.  Unfortunately, the gene has been determined to be readily transmitted and also highly adaptable.  As bacteria that contains NDM-1 encounters bacteria that doesn’t, NDM-1 could insinuate itself into the new bacteria, thus creating a larger resistant population.  The problem is particularly worrying because there is not a single antibiotic in the discovery and production process that is effective against NDM-1-containing bacteria – and because NDM-1 is highly adaptable, it could potentially change itself to resist any drugs that are developed. 

In addition to this already grim news, most of the isolates taken from India were from community-acquired infections, which implies that bacteria with the NDM-1 gene are already pervasive.  The NDM-1 gene has also already spread to the UK and Sweden – and some of the UK patients had recently traveled to India for medical treatments. 

We’re left with a good news/bad news scenario: just as we are starting to see MRSA infection rates fall, we learn that NDM-1-containing bacteria is expected to spread around the globe.

JAMA article: http://jama.ama-assn.org/cgi/content/full/304/6/641
Lancet article: http://www.thelancet.com/journals/laninf/article/PIIS1473-3099%2810%2970143-2/fulltext