Have you ever wondered how on earth vegetative bacteria can survive on dry surfaces for years? Or why when you have an outbreak and you swab the environment you don’t find the outbreak strain even though you’re pretty sure it’s there? Or why a disinfectant that gets a 4-log reduction in the lab can’t eliminate a couple of hundred cfu of bacteria from a dry surface? Dry surface biofilms could be the answer to all these questions! I was involved in a multicentre survey of dry biofilms from across the UK, and we identified dry surface biofilms on 95% of the 61 samples there were tested. Worryingly, viable MRSA was identified on 58% of the surfaces! We need to think carefully about how much of a risk dry surface biofilms present, and whether we need to do more to tackle them.
This one is for lovers of the brown stuff (no, the other brown stuff). I was taken by a large impressive epi study published in AIM showing that coffee consumption is associated with reduced all-cause mortality. Part of this seems to be tied up in a modified inflammatory response. Whilst the study didn’t mention infection specifically, clearly infection and inflammation are closely linked. So, this got me to asking whether anybody has looked at coffee consumption and infection / AMR outcomes?
by Andreas Voss and Eli Perencevich,
During the recent ICPIC 2017 and a pre-meeting think tank, the sense and non-sense of RCTs looking at various infection control measures was a major point of discussion during many sessions. Data from well-designed quasi-experimental studies, epidemiological evidence, and logic seems to vanish, whenever a new RCT is published, even if the results are not applicable to situations that are non-endemic, have higher or lower compliance with the preventive measures in question, or whether the intended measures were actually applied within the intended patient group. Some studies seem to assume that the transmission during the first days of admission are of no consequence. Others assume that given endemicity and a high patient load, the intended measures such as single-room isolation can’t be applied, even if a patient was randomized to receive those measures.
I’m not a dog lover. Far from it in fact, however a new paper in the Journal of Hospital Infection caught my eye today. Yesterday I was sitting in the Longitude Prize Advisory Committee meeting bemoaning the lack of ‘left field’ ideas coming forward. Harrison himself, winner of the original prize was such a person. He came at the problem of solving the longitude issue from a completely different direction when all of the respected science at the time was convinced that astrology was the answer. Problem: cloud, and not much of a silver lining. So we are looking for a new way to diagnose infection rapidly, distinguishing between those caused by viruses and bacteria in the hope of turning the increasing tide of resistance. So what does Fido (or Nimbus in this case) have to do with this?
I posted a blog a couple of years ago (was it really that long!) on a fascinating study suggesting that only 1/5 of S. aureus in hospital patients is hospital-acquired. My key conclusion from that study was that the number of potential sources for S. aureus that the team investigated was inadequate to draw any firm conclusions (they didn’t include staff, surfaces, or visitors). I concluded that ‘the next frontier of transmission mapping must be a more comprehensive evaluation of other potential sources…’. The authors must have been reading, because this study from the same group was published recently in Lancet ID, which is a more comprehensive evaluation of other potential sources.
It is great to see the long-awaited ‘Benefits of Terminal Room Disinfection’ (BETR-D) randomised controlled trial of a UVC automated room decon (ARD) system published, in the Lancet, no less! This study firms up the importance of environmental contamination in transmission, and demonstrates additional benefit of UVC over and above enhanced conventional methods for VRE, maybe for MRSA, but not for C. difficile.
Eurosurveillance have recently published a study from the TIMER group evaluating the impact of antimicrobial resistance on hospital mortality, excess length of stay (LOS), and cost of BSI in European hospitals. The study highlights the high cost of BSIs, especially when antimicrobial resistant.
Over the last years, we have been getting used to the fact, that commercial pig, veal, and chicken farms, as well as horse breeding, is associated with a risk of animal to human transmission of livestock-associated Methicillin-resistant Staphylococcus aureus (LA-MRSA). In the line of suspects, chicken were the last to be conformed as true source of LA-MRSA. Van Duijkeren et al (J Antimicrob Chemother 2016;71:58-62) investigated addition feathered suspects, namely dugs and turkeys.
First of all lets get Donald & friends of the list of suspects. In only one of 10 duck farms that were investigated, MRSA was found in the samples from the animals and duck houses. None of the humans living or working on duck farms, nor any part of their residence, was MRSA-positive. It therefore seems save to conclude that ducks pose no danger for transmission of LA-MRSA.
Unfortunately, the story about turkeys seems to be different. Overall, 3 of the 10 turkey farms harbored MRSA. In addition, MRSA was found in 16% of the humans and 31% of the farmhouse samples. The highest risk was seen among the turkey farmers themselves (45.5% MRSA-positive), but employees and family members (6.3%) weren’t free of risk, either. Significant risk factors found by the investigators were: having physical contact with the animals and visiting poultry houses.
In 2 out of 3 frams in which MRSA was found among the animals and the humans, whole genome mapping showed >95% homology, corroborating the strong evidence for animal-to-human transmission of MRSA on turkey farms.
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).