Thursday, December 29, 2011

What do sinks & contact lenses have in common?


Every infectious diseases doctor hates Fusarium, as therapeutic options are limited and relatively ineffective. I suspect the ophthalmologists do too, since Fusarium can cause severe keratitis in contact lens wearers.

This month's issue of Journal of Clinical Microbiology has an interesting study, funded in part by Bausch and Lomb (the maker of a particular contact lens cleaning solution that appeared to be associated with cases of Fusarium keratitis), on detecting the environmental source of the organism. Like many of the pathogens that infect profoundly immunosuppressed patients, Fusarium is also found in the environment, but unlike many other opportunistic fungal pathogens, it doesn't enter the body via the respiratory tract.

Investigators in this study sampled nearly 500 drains, primarily of bathroom sinks in 7 eastern states as far north as Pennsylvania, as far south as Florida, as well as California. They found that 66% of sink drains harbored Fusarium. Moreover, the most common strains detected are the most common strains that cause clinical infections. Importantly, this organism produces and lives in biofilm, which not only coats your sink drain, but can coat your contact lenses when they are inappropriately cleaned.

Photo: Fusarium macroconidia

Tuesday, December 27, 2011

Two papers linking XMRV and chronic fatigue syndrome retracted

Mike posted on a paper refuting the possible link between XMRV and chronic fatigue syndrome over a year ago.  Now it appears that both the 2009 Science paper and  2010 PNAS paper supporting such a link have been retracted.  The reasons for retraction of each paper appear to be very different.  For example, the story of the Science paper authors' possible image manipulation described by blogger Abbie Smith is pretty fascinating.  A great description of both retractions and related media reports can be found for both the Science and PNAS paper at Retraction Watch.  All of this is very unfortunate for the scientific community and especially the affected patients.

Sources:

Retraction of Lombardi et al., Science 326 (5952) 585-589 in Science 23 December 2011: Vol. 334 no. 6063 p. 1636 

NY Times, David Tuller 12/26/2011

h/t Ivan Oransky at Retraction Watch Blog 12/26/2011

Wednesday, December 21, 2011

Scientific inquiry, biosafety, and censorship

Investigators at the University of Wisconsin and at Erasmus University in the Netherlands have modified the H5N1 avian influenza strain so that it is not only highly virulent but also can be efficiently transmitted (at least among ferrets). Since the release of such a strain (high lethality, high transmissibility) would set the stage for a real-life version of the movie Contagion, there has been some high level angst about the wisdom of publishing the details of these experiments. This is kind of a big deal now, with a U.S. government panel appealing to two high-profile scientific journals (Nature and Science) to keep the experimental details out of the published reports of these experiments.

It appears that the scientists and institutions involved will comply with the recommendations of the National Science Advisory Board for Biosecurity. However, this work has already been presented at open scientific meetings, and detailed articles have been sent for peer review. And as Ron Fouchier, the lead investigator at Erasmus, says in today’s NY Times, “as soon as you share information with more than 10 people, the information will be on the street.” Finally, one purpose of the work was to identify those mutations that lead to greater transmissibility, so that they can be quickly detected during surveillance to help guide prevention efforts. I don’t think this can be done while simultaneously keeping those mutations a secret.

Monday, December 19, 2011

Contact precautions, and why I hate them, holiday edition

Investigators at the University of Maryland (and one or two who used to be there) are among few who are carefully examining the unintentional adverse consequences of contact precautions. Their latest publication comes out in January’s ICHE. In this paper, they report an association between starting contact precautions during hospitalization and delirium.

After adjusting for comorbid conditions, age, sex, ICU status, and length of stay, Day and colleagues found that patients newly placed under contact precautions during hospitalization were more likely to experience delirium (odds ratio 1.75, 95% CI 1.6-1.9). Delirium was defined by ICD-9 code, supplemented by use of restraints and anti-psychotic meds (this measure was validated by randomly-selected chart review). Curiously, this association did not hold for patients admitted to the hospital under contact precautions. As the authors point out, those admitted under contact precautions weren’t nearly as sick as those newly placed under precautions during hospitalization, which may account for this difference.

I’ll be the first to point out that this study doesn’t prove causation—however, the study does support our previous recommendations that patients placed under contact precautions should be carefully monitored for adverse psychiatric consequences.

Friday, December 16, 2011

Congratulations, Mike!

On being selected by HealthLeaders magazine as one of their 2011 “HealthLeaders 20”, twenty individuals they consider to be “changing healthcare for the better”. Mike’s profile can be found here. And yes, I found a photo of him wearing a tie.

No White Coats in Miami!!

I know it never gets cold in Miami, so they have one less excuse to hear from clinicians, but we wanted to share with you a new practice at Jackson Memorial Hospital in Miami, Florida.  Silvia Munoz-Price, Medical Director for Infection Control, shared that this past month they have found that white coats and scrubs were contaminated with the same pathogens as found on the hands of providers wearing the coats/scrubs. Thus, for the past 2 weeks they have been doing ID rounds wearing scrubs or bare below the elbow and without white coats. They report receiving "no negative feedback from the staff nor patients." Way to go Team Miami!

Thursday, December 15, 2011

Failure of Freakonomics

Andrew Gelman (Columbia) and Kaiser Fung (NYU) have an interesting article in the Jan/Feb 2012 issue of American Scientist that is worth a read. They review the popular Freakonomics franchise of Steven Levitt and Stephen Dubner. Freakonomics and SuperFreakonomics have set the standard for the popular statistics/economics genre, from which Gelman and Fung have both benefited. (click on their names to see their books)

However, Gelman and Fung have identified a "tendency in the Freakonomics body of work to present speculative or even erroneous claims with an air of certainty."  Overall, I'm not so worried about the small errors they outline, but the reasons for the errors are concerning and the solutions are important ones to consider in any scientific discipline, including healthcare epidemiology.

One major problem they identify is Levitt and Dubner's reliance on linear informal social networks. For example, in the original Freakonomics, the network was "Levitt did the research, Dubner trusted Levitt, the Times trusted Dubner." However, as time pressures built and the need for more unique stories increased in SuperFreakonomics the network devolved into "Levitt trusts brilliant stars such as Myhrvold or Oster, Dubner trusts Levitt, and we the readers trust the Freakonomics brand."

The solution offered was that they should "leave friendship at the door."  I think this is something all scientific disciplines could benefit from.  It is clear that editorial boards, grant review committees and annual meeting planning committees are all at risk from reliance on a "linear" closed social network (in the past called "old boys' network"). They suggest that building more "non-linearity" into their research and evaluation would protect the process from what I might call a "friendship" bias.  Excellent advice, perhaps difficult to put into practice, but worth the effort.

link: American Scientist Jan/Feb 2012

The iPatient and patient safety

Last December Mike published a piece in the Annals of Internal Medicine about how care delivery has changed on medical teaching services, including the reduction in physician interaction that now occurs as a result of residency hour limits and of the computerization of health care delivery. Residents and fellows now spend hours per day sitting in front of computer terminals, from which they must complete nearly every task (except, you know, actually seeing a patient, when telemedicine is not an option).

The NY Times has an article today on another unintended consequence of our increased reliance on computers and handheld devices—distracted doctoring. Distractions come not just from our obsession with what Abe Verghese calls the “iPatient” (that wealth of digital data each patient accumulates during even a short hospital stay), but also when we use devices for non-patient related activities during rounds, in the operating room, etc. Read the piece for yourself, and decide if this anecdotal problem is a real issue for patient safety (and if so, how to measure it, and how to implement change, when computers have become so essential for patient care). My favorite quote in the piece:

“The iPatient is getting wonderful care across America,” Dr. Verghese said. “The real patient wonders, ‘Where is everybody?’ ”

If Air Travel Worked like the US Healthcare System

Somehow, this makes me like air travel for the first time in 10 years...



h/t @IrfanDhalla via @picardonhealth

Tuesday, December 13, 2011

Patient Zero - Typhoid Mary through HIV

WNYC's Radiolab typically covers scientific and philosophical topics.  I just listened to their recent show/podcast titled "Patient Zero", which was fantastic. They start off discussing Typhoid Mary - the iconic Patient Zero. They tell 'the rest of the story', which I would guess that most of us haven't heard before. They then trace the molecular epidemiology of HIV back to a mystic first transmission to humans in Africa. They finish up with a discussion of the first ever High Five. It seems that high fives are even more infectious than infectious diseases. High fives all around.

Source: November 14, 2011 Radiolab podcast: "Patient Zero"

Monday, December 12, 2011

IDWeek Rejected Session

Dan and I are in DC today for the IDWeek Program Planning Committee meeting. Of course, we can't discuss actual sessions, so I thought of a fake session to get you excited for the 2012 joint meeting.

Session Title: Infectious Disease Issues on Sesame Street

Stop Blaming the Birds: From West Nile to Avian Flu - speaker: Big Bird

Risk factors for "Red Man Syndrome" - speaker: Elmo

Salmonella Typhimurium and Water Frogs - speaker: Kermit the Frog

Y. pestis or Francisella tularensis in Prairie Dogs - speaker: Prairie Dawn

Saturday, December 10, 2011

S. aureus decolonization: Review of the benefits

In the December 2011 Lancet ID, Andrew Simor from the University of Toronto reviewed articles listed in PubMed from 1989-2010 assessing the benefits of S. aureus decolonization. There were no surprising results. In fact, most of the conclusions were hedged.  For example he says that "some data support the use of decolonisation in surgical patients colonised with S aureus, particularly in those undergoing cardiothoracic procedures" and  "patients undergoing chronic haemodialysis or peritoneal dialysis might benefit from decolonisation, although repeated courses of treatment are needed, and the effects are modest." The hedging is not a criticism of the author, but rather due to the lack of funding for proper infection prevention studies.  What is surprising is that this is a single-author paper.  Any systematic review should be completed by more than one author, in my opinion. Another limitation is the lack of summary odds ratios. However, this is a very good literature review and a wonderful resource.

Source:  Simor AE, Lancet ID December 2011

Some norovirus with your entree?

We've blogged before about the problem of presenteeism in healthcare workers. We've all seen coworkers come to work sick and maybe have even done that ourselves. But from a public health perspective, presenteeism isn't just a problem for doctors and nurses. Those who work in the food service industry can spread gastrointestinal and other infections when they come to work sick. And they are very likely to work while sick. An article in the latest issue of The Progressive points out that 80% of food servers in the US lack paid sick leave. The Restaurant Opportunities Center United (ROC) in a survey (below) of 4,300 food service workers found that nearly 2/3 of these workers prepared or served food while sick.



ROC has also published a diners' guide (full text here), which includes information on which restaurants do and do not provide paid sick leave for their employees.

Friday, December 9, 2011

More on fecal transplants

Maryn McKenna has two new pieces on fecal transplants on her blog and in the latest issue of Scientific American (full text here). These are very well written. I plan to use these for patient education when I see patients with recurrent Clostridium difficile infection for whom fecal transplantation may be an option.

Addendum (2/1/12):  Click here to listen to an interview with Maryn McKenna on the topic of fecal transplants.

Thursday, December 8, 2011

Best news ever! A Norovirus vaccine that works!

As a parent or two young kids, I dread the slightest hint of nausea. Now, perhaps, I might have one less pathogen to fear and perhaps in old age, I can even take a cruise.

In the recent NEJM there is a report of an RCT assessing the safety, immunogenicity, and efficacy of an intranasal norovirus viruslike particle (VLP) vaccine. The study was conducted in adults aged 18 to 50. They received two doses of either vaccine or placebo and were subsequently inoculated with Norwalk virus during an inpatient challenge with 10 times the infectious dose and monitored for infection and gastroenteritis symptoms for a minimum of 4 days. (No way I'd ever volunteer for this study)

The study included 98 patients with 90 completing both injections. A Norwalk virus–specific IgA seroresponse was found in 70% of vaccine recipients. This level of response is  similar to my old Maryland colleague Samer El Kamary's 2010 JID paper that showed a 79% response rate. Vaccination significantly reduced the frequencies of Norwalk virus gastroenteritis (occurring in 69% of placebo and 37% of vaccine recipients, P=0.006) and Norwalk virus infection (82% of placebo and 61% of vaccine recipients, P=0.05). Not perfect, but still a great result.

Note: These data were also presented at earlier IDSA (2010) and ICAAC (2011) meetings.

Source: RL Atmar et al. NEJM Dec 8, 2011

Update: This news is pretty good too. (Massive drop in in-hospital deaths...in Canada)

Wednesday, December 7, 2011

Deus ex machina (Part 4): Flavonoid-like Molecules

Flavo-Noid?
When I started the Deus ex machina "meme" three weeks ago, I had no idea that so many potential novel antimicrobials would just suddenly appear.  First we had tiny magnets, then we had DNA or RNA gold nanoparticles and now word comes that there is a newly synthesized family of flavonoid-like molecules with antibacterial and antifungal activity.

Fowler et al. in PLoS ONE examined flavonoids, which are abundant plant metabolites with anti-infective activity. They used a natural flavonoid scaffold to create novel flavanones and tested their efficacy versus E coli, B subtilis, Cryptococcus neoformans and Aspergillus fumigatus. They screened eight molecules and found that 4-chloro-flavanone was the most potent antimicrobial compound.  What did Ralph Waldo Emerson say? I think it's that "We judge of man's wisdom by his hope."  Keep hope alive.

Source: Fowler et al. PLoS ONE 2011

Via:  Hampton T, JAMA 2011

Monday, December 5, 2011

Close the lid before you flush?

Photo:  Eljer Toilet Seats
A new study in the Journal of Hospital Infection evaluates what happens when a toilet that contains Clostridium difficile is flushed. Using air sampling and settle plates placed around the toilet, the investigators determined that the organism is aerosolized by the flush and could be found on most of the settle plates. Interestingly, if the toilet lid were closed prior to flushing, C. difficile could not be recovered from any of the settle plates. Unfortunately, hospital toilets typically don't have lids, and the investigators recommend that hospital toilets should be fitted with lids. However, this would mean that the undersurface of the lids would quickly become contaminated, which could also cause problems.

There's an old pearl bantered about by infectious diseases doctors that the world is covered with a thin veneer of stool. This study and the one I blogged about a few weeks ago surely provide proof of that.

Saturday, December 3, 2011

Deus ex machina (Part 3): DNA Gold Nanoparticles

Dr. Chad Mirkin
Yesterday, NPR's Science Friday had a discussion of a novel antimicrobial based a platform of spherical nucleic acids that have been developed at Northwestern. Dr. Chad Mirkin, director of the International Institute for Nanotechnology at Northwestern University, discussed the possibility that DNA or RNA gold nanoparticles could be designed to invade bacterial cells and "either turn off resistance so that a conventional antibiotic will work or, better yet, stop replication and ultimately cause bacterial cell death." Sounds pretty exciting and human trials are expected soon.

The most important thing mentioned was that DARPA, the research arm of the Defense Department, has called for development of new, next-generation antibiotics.  You can see by the host Ira Flatow's comments (quotes below) that he is perplexed as to why the Defense Department is leading the charge.

FLATOW: "And why is it that DARPA has to jump in here? What's wrong with our own medical system?"

FLATOW: "So what you're saying is that the people are willing to spend money on the military to do this where they might not in the civilian case."

Transcript: Hitting The 'Off' Switch On Antibiotic Resistance

Listen to the program (NPR 12/2/2011)

Friday, December 2, 2011

Ethical Issues in Cluster-randomized Trials

*Ottawa is in Canada
Infection prevention studies, particular ones that aim to prevent transmission of resistant pathogens (or influenza) are typically carried out at the population (e.g. ICU) level.  Thus, the study design of choice is the cluster-randomized trial.  The Ottawa Hospital Research Institute has recently held a conference and developed a set of documents highlighting the key ethical issues in these trials.

These papers cover topics such as: (1) Who is the research subject in cluster randomized trials in health research? (2) When, and from whom, is informed consent required in cluster randomized trials? (3) Does clinical equipoise apply to cluster randomized trials in health research? (4) Assessing benefits and harms in cluster randomized trials and (5) Cluster randomized trials in vulnerable populations.  These papers have or will soon be published in the open-source journal Trials.


Source: OHRI CRT Ethics page