Is increased international travel responsible for rising antibiotic resistance in New Zealand? Or is agriculture to blame? Or maybe doctors?
With antibiotic resistance now causing great concern in the medical fraternity, the Australasian Society for Infectious Diseases (ASID) has organised a session at their conference, currently underway in Surfers Paradise, Australia, to investigate the major causes of this growing issue.
Airlines, doctors, farming, drug companies and nursing homes all come under scrutiny from a series of experts exploring who is to blame for the mess we’re in and where to look to for solutions.
Addressing the role of airlines, conference speaker Dr Joshua Freeman, of the Auckland District Health Board, comments:
“Over the last 15 years, international air travel has increased to the point where in 2010 alone, a total of 940 million international tourist arrivals were recorded globally. This phenomenon, along with a concurrent increase in the international movement of migrant workers has provided an unprecedented opportunity for the transfer of antimicrobial resistant organisms across international borders, usually from countries with a high prevalence to those with a low prevalence of antibiotic resistance.”
“Over this time, one of the most well documented examples of this phenomenon has been the dissemination of extended-spectrum Beta-lactamase gene blaCTX-M-15 from its likely origin and epicenter in the Indian Subcontinent.
“A more recent and even more troubling example, also centered on the Indian subcontinent, has been the emergence of a carbapenemase gene known as blaNDM [ New Delhi metallo-beta-lactamase 1]. Since its first description as recently as 2009 in a returned traveller from India to Sweden, numerous case reports have described the dissemination of NDM to low prevalence countries worldwide including the USA, Canada, Australia, New Zealand, and the UK, mostly among patients with a previous history of hospitalization somewhere in the Indian Subcontinent.
“For NDM, unlike CTX-M-15, even the last line carbapenem antibiotics cannot be used effectively, which in many cases leaves virtually no treatment options.”
“These examples demonstrate that at the individual patient level, international travel to high prevalence countries, and in particular hospitalisation within those countries, should be viewed as an important risk factor for colonisation and subsequent infection with highly resistant gram negative organisms. Recognising the importance of this risk factor in the hospital setting is critical, because it has direct practical implications – both for the infection control measures that ought to be used and for the choice of appropriate empiric antibiotic therapy in critically ill patients.”
Further commentary collected by the Australian Science Media Centre:
Professor Lyn Gilbert, Clinical Lead of Infection Prevention & Control, Western Sydney Local Health Network, comments:
“It is not difficult to show that: inappropriate prescribing; use of antibiotic for growth promotion; importation of highly resistant bacteria; and transmission of multiresistant organisms (MROs) between hospital patients and nursing home residents all contribute to antibiotic resistance. Drug companies see no incentive in developing new drugs at great expense only to have their use restricted as much as possible. None of these drivers can be eliminated but there are proven, cost-effective strategies to mitigate them that are used inconsistently, if at all, in Australia
1. We can’t control what we can’t measure. We need consistent, comprehensive national surveillance of MROs and antibiotic use. The technology is available to capture existing data in (almost) real time from laboratory and pharmacy information systems. It would cost a bit to set it up properly, but the data would provide the basis for targeted control strategies and research.
2. Antibiotic stewardship and infection control can improve antibiotic use and prevent transmission of MROs; health administrators now acknowledge their importance as core business, but are unwilling or unable to invest in personnel and data management systems required to implement them properly.
3. Easily accessible, relevant surveillance data and expert advice can change health professionals’ behaviour, improve antibiotic use and patient outcomes and rapidly reduce emergence and spread of MROs.
4. More rapid laboratory diagnosis and new models for funding development of new antibiotics will be needed in future.”
Distinguished Professor Ian Charles, Director of the ithree institute at the University of Technology Sydney, comments:
“The battle against infectious disease will never be won – it’s an ongoing war. Bugs are everywhere, they have been with us since the early origins of life on the planet and they are very smart at adapting. So the question isn’t ‘is the rise of superbugs resistant to antibiotics a major issue’: that is now a given. The question is ‘what can we do about it to avoid a return to the pre-antibiotic era’.
“Fortunately recent major progress in high-throughput genomics and next generation sequencing have advanced to a stage that they offer a very promising route to help with detection and surveillance and, more importantly, enable research aimed at discovering new and innovative therapeutics for the treatment of infectious disease. In this endeavour we are entering an age of ‘big data’ where bioinformatics will provide the ability to make sense of the wealth of new information we uncover.”
Professor Steve Djordjevic, from the three institute at the University of Technology Sydney, and research leader on a new biosecurity collaboration with the NSW DPI, comments:
“The heaviest use of antibiotics is not in humans, but is in animal production and agriculture more broadly. This practice is leading to a build-up of antimicrobial residues as environmental pollutants. Whilst reducing the use of antibiotics in food production is of course essential, what we need right now is better detection and surveillance so that we can get a handle on where the reservoirs of Multi Drug Resistance (MDR) genes are ‘hiding’ in the environment, to help us understand how to better manage healthcare and animal husbandry in order to curtail the problem of antibiotic resistance.
“Advancing the fundamental understanding about how reservoirs of genes responsible for antibiotic resistance move between ‘good’ and ‘bad’ (disease-causing) bacteria, and the link between animals, the environment and humans is now providing a vital route to better tracking – and hence control – of drug resistant infections.”