Infection Prevention 2015, the annual conference of IPS, was held in Liverpool this year. I’m delighted to say that the abstracts from the submitted science are published Open Access in the Journal of Infection Prevention. This first instalment of my report will be “bug-focussed”, followed by another two on different themes:
Part I: Beating the bugs
The conference kicked off with fellow ‘Reflections’ blogger Prof Andreas Voss. By Andreas’ own admission, he was given a curve-ball of a title: ‘CRE, VRE, C. difficle or MRSA: what should be the priority of infection prevention?’ [No idea where that could have come from…] Andreas developed a framework for grading the priority of our microbial threats, accounting for transmissibility, virulence, antibiotic resistance, at-risk patients, feasibility of decolonisation, cost, and impact of uncontrolled spread. And the result? Any and all microbes that cause HCAI should be a priority of infection prevention. Even those that seem to have less clinical impact (such as VRE) are good indicators of system failure. If we focus too much on one threat, we risk losing sight of the bigger picture.
Next, Dr Jennifer Gardy (Canadian CDC) told the story of an outbreak using whole genome sequencing (WGS). I was struck by how far DNA sequencing has come in such a short time frame: to think that you can now sequence a genome in a USB drive on your laptop! The roadblock to its useful application is now not the sequencing per se, but the bioinformatics and useful clinical application. But, if that can be solved, WGS offers the potential to turn a ‘plate of spaghetti’ epidemiological picture into a clear transmission network, and allow you to ‘read outbreaks like a book.’ Jennifer used the now infamous NIH CPE outbreak as an example, which, in highlight was really rather small; perhaps that is the point! But the potential applications of WGS go far beyond simple outbreak investigation, encompassing epidemic tracking and metagenomics, and possibly even routine use in clinical microbiology. It was telling that only 8% of the audience had participated in a WGS study; I suspect this will be 98% in 5 years’ time.
Carole Fry’s guest lecture offered some historical perspective, tracking the introduction of first standard and then transmission based precautions from the early 1990s. Although standard precautions are a great idea in principle, they (ironically) lack standardisation! The CDC family of precautions make sense to me, and I remain disturbed by the movement away from contact precautions in some parts of the US. The reduction in MRSA bacteraemia in the UK has been nothing short of spectacular – but what has effected this miracle? And finally, what of developments in surveillance and public reporting? There’s good, there’s bad and there’s ugly – but, on balance, public scrutiny has been a driver for positive change. And the reduction of MRSA bacteraemia is case in point.
Update on resistant Gram-negatives
Prof Peter Hawkey (Birmingham), Prof Ed Septimus (Texas), and fellow ‘Reflections’ blogger Martin Kiernan provided different aspects of the evolving Gram-negative resistance crisis. Prof Hawkey began with an overview of the epidemiology of multidrug-resistant Gram-negatives (MDR-GNR), highlighting the gulf in epidemiology between the Enterobacteriaceae and non-fermenters. The naughty sexual promiscuity of Gram-negative bacteria was a theme throughout the conference, resulting in inter and intra-species horizontal gene transfer. Prof Hawkey highlight disturbing trends of ESBL in India and China (>60%), CPE in a Pakistani PICU (>70%), rapid emergence of CPE (overlaid with colistin resistance) in Italy, and Israel (perhaps seeded with KPC by New Yorkers), and frequent colonisation of returning travellers from SE Asia with ESBLs. Another threat is contamination of water sources, including effluents from sewage works, which may enrich antibiotic resistant bacteria. The risk to our hospitals is silent transmission of CPE, which will be halted by solid admission screening, accurate surveillance, and careful isolation – learning from outbreaks of antibiotic-resistant Klebs decades earlier.
Prof Septimus was given the tricky task of explaining how to keep CPE at the hospital door. Put simply, carbapenems are the “big guns” and carbapenemases are “bigger guns”. The rise of CPE in the USA has been nothing short of meteoric; we are on the road to a crisis – and need to change course to succeed in bringing CPE under control. Challenges include medical tourism, queries over how best to detect CPE, regional spread, and uncertainty around which interventions are effective. Given this uncertainty, a bundle of interventions is called for – and a bundled approach has been shown to be effective in some parts of the US. But we need to work closely together to halt the spread of CPE. “Sibling rivalry” in each region needs to be suspended if this approach is to be effective.
Martin Kiernan delved into the depths of the hospital environment to explore the potential role of surfaces in the transmission of Gram-negative rods. Martin conjured a picture of complex transmission networks, involving multiple contacts with contaminated hands and surfaces, rather than linear transmission pathways. But since Gram-negative bacteria can survive on dry surfaces for longer than you may expect (aided in part by biofilms), are not reliably removed by conventional methods, and admission to a room previously occupied by a patient with resistant A. baumannii and P. aeruginosa increases the risk of acquisition, we discount the role of contaminated surfaces in the transmission of Gram-negative bacteria at our peril!
My old team at GSTT and new team at Imperial presented some oral presentations and posters during the conference. (You can download the slides and poster pdfs here.) Probably the most important work presented from my colleagues was the large screening study at GSTT, identifying an extremely low carriage rate of CPE (0.1% of >4500 admissions screened). I can’t see how routine admission screening will ever be cost effective at this extremely low carriage prevalence.
Pandemic viruses: MERS & Ebola
Prof Ziad Memish (Saudi Arabia) provided an update on MERS, focussing on the infection prevention and control implications. The ECDC provides a useful epidemiological summary, including the 26 countries that have handled a case of MERS. Outbreaks in Jeddah, Saudi Arabia, and South Korea are most likely explained by simple break-downs in basic infection control. As to where the virus originated, camels carry the can, but this should be shared with bats, and probably other animal reservoirs. Oh, and we can expect to see more MERS-like viruses emerging in future as wild animals ‘urbanise’.
Ronald Kremer (MSF) provided a unique insight into the MSF response to Ebola in West Africa. Challenges were almost innumerable but included patient transport; lack of transparency & fear in contact tracing; clinical challenges; “Ebola deniers”; and safe burial practices. Ronald alluded to a day in the life of a front line local Ebola fighter: you care for a sick colleague (blood everywhere); your wife won’t sleep with you; and your land lord evicts you. I felt a keen sense of contrast between the conditions faced in West Africa and the preparedness plans laid in the UK: the high-tech Royal Free High Level Isolation Unit (which I was involved in decontaminating after the repatriated cases in the UK) is a far cry from West Africa.
Group Captain Andy Green (MoD) added further unique insight from the perspective of the UK response. As Ebola raged out of control in West Africa, the UK were busy building treatment facilities, and preparing for worst-case scenarios in the UK. The Ebola response required unprecedented civilian, military, government and NGO collaboration, which led to some jolly impressive treatment centres! Captain Green reflected that Ebola was nothing like the 1995 film ‘Outbreak’ – but conceded the odd similarity (not least the “fearbola” that ensued)! Captain Green concluded in the words of Churchill: ‘Never in the field of human conflict was so much owed by so many to so few.’ So it seems fitting that the military IPC team won the team of the year award at IPS, and Ebola Fighters were made Time’s Person of the Year.
From a personal point of view, I am especially sad that Infection Prevention 2015 is over, because it is the last year of my involvement on the organising committee. I have enjoyed helping to develop the programme for the conference over recent years, and particularly seeing an increase in the quality and quantity of submitted abstracts (from around 30 five years ago to more than 150 at this conference). I am sure that this conference will continue to go from strength to strength, and look forward to attending Infection Prevention 2016 as a delegate!