Persistent Pathogens

 

Credit CDC PHIL

 

# 6757

 

 

While exotic emerging viruses tend to garner the greatest headlines, old school bacterial nemeses like C. diff, S. aureus, and A. baumannii exact an impressive toll each year, killing tens of thousands of hospitalized patients and adding billions of dollars in health care costs.

 

This oft quoted assessment from the CDC on the burden of Hospital Acquired Infections in the United States is from 2010.

 

A new report from CDC updates previous estimates of healthcare-associated infections. In American hospitals alone, healthcare-associated infections account for an estimated 1.7 million infections and 99,000 associated deaths each year. Of these infections:

• 32 percent of all healthcare-associated infection are urinary tract infections
• 22 percent are surgical site infections
• 15 percent are pneumonia (lung infections)
• 14 percent are bloodstream infections

 

Hospitals are engaged in a perpetual warfare against the spread of infection - and while progress is being made - many pathogens continue to slip past the infection control safeguards.

 

The American Journal of Infection Control - the official publication of APIC – provides a sobering overview of this daily battle, and while infection control techniques are improving, bacteria can be masters at evading even the most stringent measures.

 

One of the toughest bacteria that hospitals must deal with is multidrug-resistant (MDR) Acinetobacter baumannii, which in recent years has made headlines as the cause of difficult to treat wound infections among our troops serving in the Middle East.

 

Acinetobacter (of which there are many varieties, but A. baumannii is most often linked to human infection ) are ubiquitous in nature, and can be found in  soil, water, animals and humans. A very hardy species, they can survive for extended period of time on inanimate surfaces, making them difficult to control in a health care setting.

 

Yesterday the AJIC carried an article on just how tough eradicating this bacteria really is.

 

The effect of terminal cleaning on environmental contamination rates of multidrug-resistant Acinetobacter baumannii

Paula Strassle, BS, Kerri A. Thom, MD, J. Kristie Johnsonm, PhD(ABMM), Surbhi Leekha, MBBS, MPH, Matthew Lissauer, MD, FACS, Jingkun Zhu, MS, Anthony D. Harris, MD, MPH

We evaluated the prevalence of multidrug-resistant Acinetobacter baumannii environmental contamination before and after discharge cleaning in rooms of infected/colonized patients. 46.9% of rooms and 15.3% of sites were found contaminated precleaning, and 25% of rooms and 5.5% of sites were found contaminated postcleaning. Cleaning significantly decreased environmental contamination of A baumannii; however, persistent contamination represents a significant risk factor for transmission. Further studies on this and more effective cleaning methods are needed.

 

The full text to this study are available on the AJIC website, but we’ve also a brief summary via a press release.

 

Hospital cleaning protocol ineffective against A. baumannii

Washington, November 30, 2012 -- Current hospital cleaning protocol may be inadequate to rid patient rooms of multidrug-resistant (MDR) Acinetobacter baumannii, according to a study in the December issue of the American Journal of Infection Control, the official publication of the Association for Professionals in Infection Control and Epidemiology (APIC).

 

A team of researchers from the University of Maryland collected 487 cultures from 32 hospital rooms occupied by just-discharged patients with a known history of MDR A. baumannii both before and after terminal cleaning of the rooms. Over half of the rooms positive for the A. baumannii bacteria prior to cleaning remained contaminated after terminal cleaning had occurred.

 

Fifteen rooms (46.9 percent) and 41 sites (n=268, 15.3 percent) tested positive for MDR A. baumannii before cleaning. Post-cleaning, eight rooms (25 percent) and 12 sites (n=219, 5.5 percent) still tested positive for the pathogen. Sites with post-cleaning contamination included the floor (12.5 percent), call button (10 percent), door handle (9.4 percent) bedside table (7.4 percent), and supply cart (3.8 percent).

 

"Persistent room contamination serves as a potential reservoir for transmission and colonization of future room occupants," state the authors in the article. "Current cleaning techniques in terms of products used or thoroughness of cleaning may not be adequate in the decontamination of this pathogen."

 

Acinetobacter baumannii is a type of bacteria that has become increasingly prevalent in healthcare facilities and is resistant to most antibiotics. Infections from this pathogen primarily occur in very ill, wounded, or immunocompromised patients. The germ can remain on wet or dry surfaces for longer than most other organisms, making it harder to eradicate.

 

"This study shows how difficult it is to ensure removal of particularly resistant organisms from the environment even upon thorough discharge cleaning," said Anthony D. Harris, MD, MPH, lead study author and professor of epidemiology and public health at the University of Maryland School of Medicine. "With new, innovative means of monitoring cleaning processes that we have incorporated since the study was done, coupled with other infection control efforts, we are seeing lower rates of A. baumannii at our hospital."

 

 

The good news is that while difficult, control of these organisms is possible with the right measures. We’ve looked at the problem of controlling HAIs frequently in the past.  A few examples include:

 

• Last month in The Flight Of The Bacterial Intruder at how bacteria, including C. diff and MRSA, can ride air currents and contaminate surfaces more than 3 meters from a patient.

 

• In 2010, we saw a study published in the AJIC: American Journal of Infection Control that found that the more roommates you have during a hospital stay, the greater chance you will have of contracting an HAIs (Hospital Acquired Infections)  like MRSA or C. Diff.

• • Exposure to hospital roommates as a risk factor for health care–associated infection

  • Meghan Hamel, MSc, Dick Zoutman, MD, FRCPC, Chris O'Callaghan, DVM, MSc, PhD

 

• A Barrier To Good Hand Hygiene
• Study: Hospital Uniforms And Bacteria
• Study: HAIs, Universal Surveillance, & MRSA

 

 

That said, the subjects of HAIs and resistant bacteria are most consistently (and frankly, better) addressed by Maryn McKenna on her excellent Superbug Blog, and was a major focus of her book SUPERBUG: The Fatal Menace Of MRSA.

Both of which are highly recommended.

Hand Hygiene Among Doctors Exposed

 

 

# 4831

 

 

There is an old joke that says that half of all people don’t wash their hands with soap and water after using the toilet.

 

Those people are called men.

 

 

While not completely true, men do have a reputation for being less than fastidious in such matters.  

 

But you’d think that doctors . . .  particularly infectious disease doctors . . . would all faithfully wash their hands vigorously with soap and water before leaving the restroom.

 

But if you did, of course, you’d be wrong.  

 

Today we’ve an observational study conducted at two scientific conferences on the hand washing habits of doctors. 

 

The first was the 26th Meeting of the Scandinavian Society on Antimicrobial Chemotherapy (SSAC) in Tromsø, Norway, and second took place at the International Congress on Antimicrobial Agents and Chemotherapy (ICAAC) in San Francisco, CA.

 

Both took place last September, during the pandemic.

 

Observers stationed in the men’s and women’s restrooms kept track of the hand washing compliance among the men and women (mostly infectious disease specialists) attending these conferences.

 

The results, while better than others we’ve seen among the general public, were still less than comforting.

 

The study appears in the latest edition of The AJIC (American Journal of Infection Control) and is called:

 

Do as I say, not as I do: Handwashing compliance of infectious diseases experts during influenza pandemic

Anu Kantele, MD, PhD, Mari Kanerva, MD, PhD, Mikko Seppänen, MD, PhD, Jussi Sutinen, MD, PhD, Kirsi Skogberg, MD, PhD, Laura Pakarinen, MD, Iiro H.S. Jääskeläinen, MD, Inko Aho, MD, Asko Järvinen, MD, PhD, Taru Finnilä, MD Jukka Ollgren, PhD

 

 

It is a relatively short article, with just one chart displaying the HWWS (Hand Washing With Soap) compliance among men and women at these two conferences.

 

The bottom line was that in San Francisco only 69% of the men were observed to wash with soap and water, and 86% of the women.

 

In fairness, I should mention that many of the non-compliant restroom visitors did rinse their hands with water before exiting. 

 

Feel better?  I thought not. 

 

 

Hand hygiene at the Tromsø, Norway conference was even less comforting, with just 38% of the men, and 84% of the women using soap and water.

 

Last year, in a blog titled Doing The Hand Jive I wrote about a market research study conducted in 2007 by HarrisInteractive that looked at hand washing habits in 6 public venues around the United States.

 

While nine in ten (92%) adults surveyed claimed they always washed their hands after using public restrooms; just over three in four (77%) were observed doing so (down from 83% in 2005).

 

Men were less likely to wash their hands than women, with only 66% stopping to wash, as opposed to 88% of women.

 

And since I’ve never missed an opportunity to beat a dead horse, I’ve one more study to share, this time from BMC Infectious Diseases, which pretty clearly demonstrates the efficacy of hand hygiene.

 

I’ve excerpted from the abstract (and have reformatted for readability), but follow the link to read the entire (open access) study.

 

Effectiveness of alcohol-based hand disinfectants in a public administration: Impact on health and work performance related to acute respiratory symptoms and diarrhoea

 

Nils-Olaf Hubner , Claudia Hubner , Michael Wodny , Gunter Kampf  and Axel Kramer

Methods

Our study involved a prospective, controlled, intervention-control group design to assess the epidemiological and economical impact of alcohol-based hand disinfectants use at work place. Volunteers in public administrations in the municipality of the city of Greifswald were randomized in two groups. Participants in the intervention group were provided with alcoholic hand disinfection, the control group was unchanged. Respiratory and gastrointestinal symptoms and days of work were recorded based on a monthly questionnaire over one year. On the whole, 1230 person months were evaluated.

Results

Hand disinfection reduced the number of episodes of illness for the majority of the registered symptoms.

This effect became statistically significant for common cold (OR = 0.35 [0.17 - 0.71], p = 0.003), fever (OR = 0.38 [0.14-0.99], p = 0.035) and coughing (OR = 0.45 [0.22 - 0.91], p = 0.02).

 

Participants in the intervention group reported less days ill for most symptoms assessed, e.g. colds (2.07 vs. 2.78 %, p = 0.008), fever (0.25 vs. 0.31 %, p = 0.037) and cough (1.85 vs. 2.00 %, p = 0.024). For diarrhoea, the odds ratio for being absent became statistically significant too (0.11 (CI 0.01 - 0.93).