PHE have just launched an interactive database for HCAI and AMR data from England using their ‘Fingertips’ platform. The HCAI data in the module has been available for years, but was buried in pretty dense Excel spreadsheets so tricky to visualise. The Fingertips platform makes data extraction and visualisation so easy even I can do it (example below).
As you can probably tell from the title, this post comes with a warning: it presents some rather “un-PC” data, but I’ll do my best to deliver it calmly and dispassionately! My old research team from KCL have just published a paper in PLOS Medicine on the association between social and material deprivation, and MRSA.
I’ve been interested in the dynamic between hospital-associated (HA) and community-associated (CA) MRSA for years (not least because it was the subject of my PhD thesis). I wrote a review several years ago on how community MRSA should be seen as a genotypic phenomenon with epidemiological implications. Using this framework, it is possible to get your head around CA strains of MRSA beginning to cause hospital-acquired infections. The aim of this study was to use a large collection of MRSA from across several regions of London to explore the transmission dynamics and epidemiological associations of HA and CA types of MRSA.
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.
Jon posted a blog last week on mupirocin resistance in MRSA. This week, guest blogger Dr Gwen Knight (bio below) writes about a companion paper also published in the Journal of Antimicrobial Chemotherapy, which models mupirocin resistance…
It is a truth universally acknowledged, that acquiring most mechanisms of drug resistance incurs a fitness cost to the host bacterium. Determining the size of this cost and the impact that this cost will have on the spread of drug resistance is difficult. Is a 10% reduction in growth rate in the laboratory enough to stop resistance spreading in a hospital?
I’ve blogged before that mupirocin resistance is an inevitable consequence of mupirocin use. Whilst I still think that this is true, my old colleagues from GSTT / KCL have just published an article suggesting that mupirocin resistance in MRSA has more to do with clonal variation than with mupirocin use.
The study is part of an ambitious project to sequence the genome of around 1000 MRSA isolates from across Central and South-East London (Guy’s and St. Thomas’, King’s, and Lewisham). Each isolate was then tested for phenotypic high (HMR) and low (LMR) mupirocin resistance, the genome was scoured for the genetic determinants known to be associated with mupirocin resistance, and clone was derived from the genome sequence. Risk factors for both HMR and LMR were then explored.
Sometimes waiting for research highlighting an issue that you know is a problem is like waiting for a bus.. Following on from my colleague @jonotter who last week posted about MRSA spread in nursing home settings, I was interested to read this new paper from the USA, published in the Journal of the American Geriatric Society. The study notes the high prevalence of Multi-Drug Resistant Organism (MDRO) carriage in nursing homes that was in excess of that in hospital settings and sought to determine any associations. The findings are interesting, if not surprising.
There is an emerging feeling that we need to start spreading the focus of infection prevention and control beyond acute hospitals. There has always been a sense that standards of infection control outside of acute settings are, shall we say, “different” to acute hospitals (aka non-existent) so it’s great to see a study of an infection control intervention in nursing homes.
The study was a cluster randomised controlled trial of MRSA screening, decolonisation and enhanced environmental disinfection vs. standard precautions in 104 of 157 nursing homes in a Swiss region. The authors chose a rather unusual, pragmatic endpoint of the prevalence of MRSA colonisation after 12 months.
(from Statens Serum Institut, EPI-News, N023-2015)
‘The number of hospital-acquired cases observed in 2014 increased to 95 from 52 cases in 2013, but still comprise only a limited share of the total number of cases (3%). The number of MRSA cases of the CC398 type, which is closely associated with pigs, increased substantially from 643 cases in 2013 to 1,276 cases in 2014 and comprised 43% of the total number of cases. Community-acquired MRSA, i.e. in persons with no known contact to pigs, hospitals or nursing homes, comprised 946 cases in 2014, compared with 821 cases in 2013. In 478 of these cases (51%), there was known exposure to a person with MRSA, most frequently a member of the household (92%). In 56 cases, MRSA was isolated from blood, corresponding to 2.9% of all S. aureus bacteraemia cases, which is a substantial increase with respect to recent years, but the figure remains low compared with other European countries.’
And here I stop citing the report. For those interested in the complete report, please follow the link: MRSA Denmark.
If, in 2004, I’d told an MRSA expert that there would be around only 200 MRSA bloodstream infections (BSI) per quarter in England throughout 2014 they’d have laughed out loud. This is because, back in 2004, there were sometimes more than 100 MRSA BSI per month in some London hospitals (and around 2000 per quarter nationally), combined with a general perception that only around 30% of MRSA BSI are preventable. How wrong we were.
The reduction of MRSA BSI in England has been dramatic, with a reduction in the region of 90% achieved over a 5 year period. I was asked to speak on “The English MRSA Miracle” at a conference in Portugal today, so thought I’d share my thoughts. You can download my slides here.
It’s difficult to pin down exactly what is behind the ‘MRSA Miracle’ since quite a number of interventions occurred at more or less the same time (Figure 1):
Some have postulated that the national cleanyourhands campaign is responsible for the dramatic success. Indeed, there is a BMJ study that makes this case, showing that the national significant increase in the use of soap and water and alcohol gel correlated with the reduction in MRSA BSI. However, I contend that this can’t be the case because what has happened to the rate of MSSA and E. coli BSI over the same period? Nothing – no reduction whatsoever. If increases in hand hygiene compliance really do explain the reduction in MRSA BSI, then they should also reduce the rate of MSSA BSI (unless the increase in hand hygiene compliance only occurred after caring for MRSA patients, which seems unlikely).
There’s a more important epidemiological point here though. High-school tells us to change one variable at a time in science experiments. And yet in this case multiple variables were modified, so it’s not good science to try to pin the reduction to a single intervention, no matter how strong the correlation. (I should add that the authors of the BMJ study do qualify their findings to a degree: ‘National interventions for infection control undertaken in the context of a high profile political drive can reduce selected healthcare associated infections.’)
There has been much discussion about whether we should be investing in a universal or targeted approach to infection control. The failure of improved hand hygiene to make any impact on MSSA BSI suggests that targeted interventions are behind the reduction in MRSA. So what targeted interventions were implemented that may have contributed to the decline? MRSA reduction targets were introduced in 2004, a series of ‘high-impact interventions’ focused mainly on good line care in 2006 and revised national guidelines in 2006 (including targeted screening, isolation and decolonization) all contributed to a surge of interested infection control. Infection control teams doubled in size. Infection control training became part of mandatory induction programmes. And hospital chief executives began personally telephoning infection control to check “how many MRSA BSIs” they had left.
The ‘English MRSA Miracle’ has not been matched in most parts of Europe, except in France, which has had a rather more steady ‘MRSA Miracle’ of its own (Figure 2).
What is behind the failure of most European countries in controlling MRSA? The barriers are multifactorial, but include high levels of antibiotic use, a lack of single rooms for isolating patients, infection control staffing, and, of course, crippling national debt (Figure 3).
If the English MRSA Miracle is to be replicated across Europe, it will take concerted national initiatives to raise the profile of infection control, combined with considerable investment, which is challenging in these times of austerity.
The ECDC recently released their 2013 report, which includes 2013 data. The data are on the whole fairly depressing for more parts of Europe, with high and increasing rates of resistance to important antibiotics in common bacteria. So it was not surprising to see ECDC issue a corresponding press release focusing on worrying resistance to last-line antibiotics.
I’ve chosen a few illustrative countries from this useful interactive database. Carbapenem resistance in Enterobacteriaceae (i.e. CRE) is one of the most concerning challenges facing us right now. So it’s not good to see continued high rates of carbapenem resistance in K. pneumoniae in Greece, and the seemingly inexorable increase in Italy (Figure 1). It’s worth noting that these are invasive isolates, the majority of which would be bloodstream infections. And the mortality rate for a CRE bloodstream infection is around 50%…
In some ways, the steady increase in multidrug-resistant K. pneumoniae from many parts of Europe, illustrated in Figure 2, is even more concerning than the sharp increases in CRE in some parts of Europe. If you draw a mental trend line for Italy and Portugal, it doesn’t look good.
The picture for P. aeruginosa (and I suspect the other non-fermenters like A. baumannii, which isn’t included in EARS-Net) in terms of carbapenem resistance is different to the Enterobacteriaceae (Figure 3). Rates are high in Greece, intermediate in Italy and Portugal, and low in the UK. But the trend is stable.
And let’s not forget about MRSA (Figure 4). The UK and some other European countries have done a tremendous job in reducing the transmission of MRSA. This has had an interesting and somewhat unexpected effect on the rate of methicillin-resistance in S. aureus, which has also reduced considerably. I suspect this is a consequence of interrupting the transmission of MRSA, but failing to prevent the spread of MSSA. Put another way, if MRSA and MSSA fell in tandem, the rate of methicillin-resistance in S. aureus would remain constant. The impressive reductions of MRSA reported in the UK have not been replicated everywhere in Europe. Portugal in particular increased from less than the UK in the early 2000s to more than the UK today. There is some evidence that the national campaign in Portugal to reduce healthcare-associated MRSA is making some impact, with a notable reduction in MRSA rate in 2013.
In summary, it’s not all doom and gloom. The reductions in MRSA in the UK and elsewhere show that reducing the transmission of these antibiotic resistant bacteria can be done. But it takes considerable investment and national focus. Without this, it’s difficult to see the trends in antibiotic resistance, including to last-line agents, continuing to increase in some parts of Europe.