Vomiting Larry And His Aerosolized Norovirus

Credit UK’s Health & Safety Laboratory

 

# 6812

 

Sounding vaguely like an invention lifted from one the Tom Swift books of my youth (e.g. Tom Swift and His Atomic Earth Blaster, Tom Swift and His Electric Rifle), Vomiting Larry is a dummy that . . . well, vomits.

 
All in the name of science, of course.

 

In order to test how well (and how far) Norovirus (aka `The Winter Vomiting Bug’) can spread through the air, scientists have created a dummy that spews. A move, I suspect, prompted primarily by a lack of willing  human volunteers for this study.

  

By adding a florescent dye marker to Larry’s `vomitus’, researchers at the UK’s Health & Safety Laboratory have determined that droplets – too small to be readily seen – can end up as far as 3 meters away from the source.

 

Vomiting Larry featured on the BBC website

Winter Vomiting bug has been very much in the news of late due to the recent major outbreaks of norovirus, which causes this illness. A recent article on the BBC news website has highlighted the work that the Health and Safety Laboratory has done to establish the extent with which the surrounding environment becomes contaminated when an individual vomits.

 

This is an important consideration for infection control during outbreaks of norovirus where the key symptom is projectile (forced) vomiting. Catherine Makison of HSL's Occupational Hygiene Unit has developed a humanoid simulated vomiting system affectionately known as "Vomiting Larry".

 

"Larry" was primed with a vomitus substitute (to which a fluorescent marker was added so as to identify even small splashes post vomiting), and simulated vomiting was carried out. As the BBC video shows graphically, these tests demonstrated the full extent of room contamination post vomiting and that small droplets can spread over three metres from the "Larry" system, which are not easily visible under standard white hospital lighting.

 

HSL studies have shown that Norovirus can be isolated from these small droplets at concentrations capable of causing an infection. This information might highlight why this robust and highly infectious virus is transmitted between people so readily.

 

The outcomes of these studies have contributed to reviews of healthcare guidance in hospitals and are due to be published in relevant journals in the near future.

 

The role of direct aerosolized human-to-human transmission of norovirus remains less than clear, although there are numerous anecdotal reports that suggest that it happens.

 

The CDC – in a an MMWR report from 2011 called Updated Norovirus Outbreak Management and Disease Prevention Guidelines describes transmission thusly:

 

Transmission

Norovirus is extremely contagious, with an estimated infectious dose as low as 18 viral particles (41), suggesting that approximately 5 billion infectious doses might be contained in each gram of feces during peak shedding. Humans are the only known reservoir for human norovirus infections, and transmission occurs by three general routes: person-to-person, foodborne, and waterborne.

 

Person-to-person transmission might occur directly through the fecal-oral route, by ingestion of aerosolized vomitus, or by indirect exposure via fomites or contaminated environmental surfaces.

 

 

And last May, in Norovirus: The Gift That Keeps On Giving, we looked at an incident involving a girl’s soccer team where 17 girls were exposed via a reusable grocery bag, likely contaminated from an airborne route.

 

 

While one of the keys to prevention is good hand hygiene, unlike with many other bacteria and viruses, alcohol gel doesn’t do a particularly good job of killing the virus (see CMAJ: Hand Sanitizers May Be `Suboptimal’ For Preventing Norovirus).

 

Which makes a good old fashion hand scrubbing with soap and water the best preventative.

 

As new studies that show the aerosolized spread of noroviruses are published, hospital infection control policies may need to revisit the use of facemasks for HCWs caring for infected patients.

»» Read More

Study: Weighing The Risks Of MRSA Colonization

MRSA - Photo Credit CDC

# 6807

 

The CDC tells us, in their Definition of MRSA page, that:

 

While 25% to 30% of people are colonized* in the nose with staph, less than 2% are colonized with MRSA (Gorwitz RJ et al. Journal of Infectious Diseases. 2008:197:1226-34.).

*Colonized:
When a person carries the organism/bacteria but shows no clinical signs or symptoms of infection. For Staph aureus the most common body site colonized is the nose.

 

 

Although 2% doesn’t sound like a lot, there are signs that number may be increasing. Once considered primarily a hospital acquired infection, CA-MRSA (community acquired) is growing in incidence.

 

As an example, in Firefighters & Paramedics At Greater Risk Of MRSA and Firefighters & MRSA Revisited we looked at research showing a 10x’s greater incidence of MRSA colonization (20%) among a sampling of firefighters tested in Washington State.

 

Since one person’s colonization can become another person’s infection, topics of debate have included:

 

1. What risks are there to the individual from long-term colonization?
2. What risks are there to others In the Community or a household?
3. What risks are there to others in a hospital or long-term care environment?
4. What (if any) steps should be taken to decolonize carriers, and in what setting (hospital admission? Outpatient?) is decolonization desirable and effective?

 

There are, it seems, few easy answers. 

 

Mary McKenna, editor of the terrific Superbug Blog, took a look at the problems inherent with the decolonization of MRSA carriers in 2009 with:

 

Decolonization: disappointing news 

The upshot was that while studies have shown that decolonization procedures on hospitalized patients about to undergo surgery can reduce infections, the value to other patients is far less clear.

 

And as Maryn points out, overuse of mupirocin – the primary antibiotic used to decolonize patients –can lead to increased resistance over time.

 

And Mary also tells of a paper published in Infection Control and Hospital Epidemiology, that evaluated the success of decolonization protocols in 3 major Illinois hospitals, that less than reassuring results: a temporary reduction in patients’ being colonized with MRSA, but no success in preventing infection.

 

In 2011, the Infectious Diseases Society of America published their clinical practice guidelines for treating MRSA in adults and children, where they endorse `decolonization’, but only under select scenarios (note SSTI = Skin & Soft Tissue Infection):

 

14. Decolonization may be considered in selected cases if:

• i. A patient develops a recurrent SSTI despite optimizing wound care and hygiene measures (C-III).

• ii. Ongoing transmission is occurring among household members or other close contacts despite optimizing wound care and hygiene measures (C-III).

 

• ii. Contacts should be evaluated for evidence of S. aureus infection:
• a. Symptomatic contacts should be evaluated and treated (A-III); nasal and topical body decolonization strategies may be considered following treatment of active infection (C-III).
• b. Nasal and topical body decolonization of asymptomatic household contacts may be considered (C-III)

 

But what, if anything, to do about asymptomatic carriers who are colonized, but not infected with MRSA remains up in the air.

 

Hospital strategies to contain and control MRSA range from passive surveillance to aggressive `search & destroy’ policies – with variations in between.

 

Passive surveillance – which is the most commonly used protocol in the United States – involves  testing only those who have clinical signs or symptoms of
MRSA.

Since patients may be colonized without exhibiting outward signs, this will fail to detect a great many carriers of the bacteria.

Active Surveillance – requires the testing of high risk admissions (ie.  Hx of MRSA, Antibiotic Use, Admission to Hospital in past year, Resident of Long-term care facility, etc.) for the bacteria.

Patients testing positive may be isolated and decolonized or treated, with strict infection control precautions enforced.

Universal Surveillance – takes the above steps to a higher level, where all admissions and personnel are routinely swabbed and tested for MRSA.

“Search & Destroy” – which is the most intensive protocol, has been used successfully in countries like Finland, Denmark and the Netherlands.

It combines Active or Universal Surveillance with testing of patients in high-risk wards at intervals and prior to discharge.

 

The reluctance to adopt the more aggressive of these measures have been the costs, the inconvenience to patients and their visitors, and quite frankly, objections by some hospital staff over being repeatedly tested.

A recent study appearing in Critical Care Medicine, looked at the effects of a strict S&D policy instituted at a rural trauma center, and found an immediate reduction specific types of HAIs (Hospital Acquired Infections) after implementation.

 

Search & Destroy (S&D): Eradication of Mrsa Colonization Is Associated With Decreased Mrsa Infections in Trauma Patients

Borst, Gregory; Waibel, Brett; Toschlog, Eric; Coogan, Michael; Skarupa, David; Rotondo, Michael; Ramsey, Keith

Conclusions: Search and destroy is associated with significant decreases in the incidence of MRSA VAP and CLABSI in trauma patients. Decreases in MRSA CAUTI and wound infections were also seen after the implementation of this program. Pre-emptive strategies to identify and eradicate MRSA are worthwhile endeavors in terms of preventing nosocomial infection.

 

Despite its critics, S&D policies have often shown reductions in HAIs. 

 

Which brings us to another study, published last week in the journal Antimicrobial Agents and Chemotherapy, that finds (among a relatively small cohort of patients) that colonization with MRSA posed a substantial risk of MRSA infection, increased mortality, or readmission to the hospital, compared to patients without MRSA colonization.

 

 

Long-Term Risk for Readmission, Methicillin-resistant Staphylococcus aureus (MRSA) Infection, and Death among MRSA-Colonized Veterans.

Quezada Joaquin NM, Diekema DJ, Perencevich EN, Bailey G, Winokur PL, Schweizer ML.

Source

Division of Infectious Diseases.

Abstract

Background: While numerous studies assessed outcomes of MRSA colonization over the short term, little is known about longer-term outcomes after discharge. An assessment of long-term outcomes could inform the utility of various MRSA prevention approaches.

Methods: A matched cohort study was performed among Veterans Affairs (VA) patients screened for MRSA colonization between the years 2007 and 2009 and followed to evaluate outcomes until 2010. Cox proportional hazard models were used to evaluate the association between MRSA colonization and long-term outcomes such as infection-related readmission, and crude mortality.

Results: 404 veterans were included, 206 of whom were MRSA carriers and 198 who were non-carriers. There were no culture-proven MRSA infections on readmission among the non-carriers, but 13% of MRSA-carriers were readmitted with culture proven MRSA infections on readmission (P<0.01).

MRSA carriers were significantly more likely to be readmitted, be readmitted more than once due to proven or probable MRSA infections, and be readmitted within 90 days of discharge compared to non-carriers (p<0.05). Infection-related readmission (adjusted hazard ratio [AHR] =4.07; 95% confidence interval [CI]: 2.16, 7.67) and mortality (AHR=2.71; 95% CI: 1.87, 3.91) were significantly higher among MRSA carriers compared to non-carriers, after statistically adjusting for potential confounders.

Conclusions: Among a cohort of VA patients, MRSA carriers are at high risk of infection-related readmission, MRSA infection and mortality compared to non-carriers. Non- carriers are at very low risk of subsequent MRSA infection. Future studies should address whether interventions such as nasal or skin decolonization could result in improved outcomes for MRSA carriers.

Although based on a small cohort, this study suggests that being colonized (but not infected) with MRSA is a significant risk factor for future infection, and if these findings can be confirmed by others, may influence how MRSA colonization is viewed in the future.

 

Despite some recent improvements in MRSA rates among hospitalized patients in the United States, HAIs (which include many other pathogens) continue to exact a heavy toll. 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 infection

For more on MRSA, and many other antibiotic-resistant threats, you can do no better than to visit Maryn McKenna’s terrific Superbug Blog, and to read her book Superbug: The Fatal Menace of MRSA . . . which won last year’s  NASW Science in Society Journalism Award.

You’ll find my review of her book HERE

»» Read More

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.

»» Read More

A Barrier To Good Hand Hygiene

 

 

 

# 5939

 

 

It sounds counter-intuitive. 

 

That the use of latex (or vinyl) gloves could contribute to reduced hand hygiene compliance in health care settings. 

 

But that is exactly what a study - published in the December issue of Infection Control and Hospital Epidemiology – has uncovered.

 

The study, which was conducted at 15 hospitals in the UK, found that hand hygiene compliance – even in this age of heightened awareness of infection control - was `disappointingly low’.

 

Overall hand hygiene compliance was observed to be just 47.7%, while the use of gloves was associated with a further decrease to just 41%.

 

It would appear that the use of gloves can lead to a false sense of security, and the result is a reduction in hand hygiene.

 

The following press release comes from SHEA, the  Society for Healthcare Epidemiology of America. 

 

Latex gloves lead to lax hand hygiene in hospitals, study finds

CHICAGO -- Healthcare workers who wear gloves while treating patients are much less likely to clean their hands before and after patient contact, according to a study published in the December issue of Infection Control and Hospital Epidemiology, the journal of the Society for Healthcare Epidemiology of America. This failure of basic hand hygiene could be contributing to the spread of infection in healthcare settings, the researchers say.

 

Glove use is appropriate for situations when contact with body fluids is anticipated or when patients are to be managed with contact precautions. However, use of gloves should not be considered a substitute for effective hand hygiene practices taking place before and after patient contact. Although gloves can reduce the number of germs transmitted to the hands, germs can sometimes still get through latex. Hands can also be contaminated by "back spray" when gloves are removed after contact with body fluids.

 

The researchers, led by Dr. Sheldon Stone of the Royal Free Hospital NHS Trust, observed more than 7,000 patient contacts in 56 intensive care and acute care of the elderly wards in 15 United Kingdom hospitals, making this one of the largest and most detailed studies on gloves and their impact on hand hygiene. Overall, the study found that hand hygiene compliance was "disappointingly low," at just 47.7 percent. Compliance was even lower in instances where gloves were worn, dipping to just over 41 percent.

 

"The chances of hands being cleaned before or after patient contact appear to be substantially lower if gloves were being worn," said Dr. Stone, the principal investigator. "We call this the phenomenon of the 'Dirty Hand in the Latex Glove.'"

(Continue . . . )

 

Cite: Christopher Fuller, Joanne Savage, Sarah Besser, Andrew Hayward, Barry Cookson, Ben Cooper, Sheldon Stone. The Dirty Hand in the Latex Glove: A Study of Hand-Hygiene Compliance When Gloves Are Worn. Infection Control and Hospital Epidemiology 32:12 (December 2011)

 

Given the huge burden of HAIs (Hospital Acquired Infections), the subject of hand hygiene comes up frequently in this blog. 

 

You’ll find a lot more on this subject in last month’s Giving Germs A Helping Hand, which looked at low handwashing compliance among doctors and other healthcare providers.

 

On May 5th of this year the World Health Organization promoted a CLEAN YOUR HANDS DAY  to encourage HCWs to improve and sustain hand hygiene practices around the world.

 

Clean Care is Safer Care

First Global Patient Safety Challenge
Clean Care is Safer Care

 

Additionally, the CDC’s hand hygiene website  has many resources, including a link to a new iPad/iPhone application called iScrub.

 

 

To round out this entry, some oldies but goodies from the AFD archives.

Doing The Hand Jive

Hand Hygiene Among Doctors Exposed

Gonna Wash Those Germs Right Off Of My Hands

»» Read More

Before You Ask To Borrow Someone’s Cell Phone . . .

 

 

# 5898

 

 

Just in time for Global Handwashing Day – which is tomorrow, October 15th – we’ve a report from the London School of Hygiene & Tropical Medicine that should give one pause before asking to borrow another person’s cell phone.

 

Contamination of UK mobile phones and hands revealed

One in six mobile phones in the UK is contaminated with fecal bacteria, researchers found

 

One in six mobile phones in Britain is contaminated with faecal matter, according to new research released ahead of Global Handwashing Day.

 

Experts say the most likely reason for the potentially harmful bacteria festering on so many gadgets is people failing to wash their hands properly with soap after going to the toilet.

 

The findings of the UK-wide study by scientists from the London School of Hygiene & Tropical Medicine and Queen Mary, University of London also reveal a tendency among Britons to lie about their hygiene habits.

 

Although 95% of people said they washed their hands with soap where possible, 92% of phones and 82% of hands had bacteria on them. Worryingly, 16% of hands and 16% of phones were found to harbour E. coli – bacteria of a faecal origin. Harmful E. coli (Escherichia coli) is associated with stomach upsets and has been implicated in serious cases of food poisoning such as the fatal O157 outbreak in Germany in June.

 

(Continue . . .)

 

 

BBC News has a short (2 minute) video on this story, showing how the testing of mobile phones was accomplished.

 

 

While cell phones were the subject of this study, in truth anything and everything we touch can harbor bacteria.  Door knobs, computer keyboards, shopping cart handles, elevator buttons, credit cards, cash . . . .

 

And as the movie `Contagion’ pointed out so effectively, we touch our faces 3 to 5 times every waking minute, and in between we are touching hundreds of other (likely contaminated) surfaces every day.

 

The opportunities for introducing pathogens into your body via your eyes, nose or mouth are abundant, and your only real defense is washing your hands as often as possible.

 

And it isn’t just bacteria, like Staph, MRSA, or E. coli that can contaminate surfaces. Viruses can live for hours – and under the right condition, sometimes days – on inanimate surfaces.

 

With cold and flu season upon us, it is all the more reason to carry (and use) a bottle of alcohol sanitizer and to seek out opportunities to wash your hands with soap and water as often as possible.

 

Although better than nothing, hand sanitizers are not always enough. In CMAJ: Hand Sanitizers May Be `Suboptimal’ For Preventing Norovirus we saw how these handy sanitizers are not always effective against C. Diff and Norovirus.

 

In Fomite to Fingers To Face: A Triple Play Combination, we looked at how long some of these pathogens could remain viable on surfaces and act as a vehicle of transmission.

 

The 2007 study Significance of Fomites in the Spread of Respiratory and Enteric Viral Disease by Stephanie A. Boone,& Charles P. Gerba found that most viruses survived longer on nonporous surfaces (metal or plastic), and that respiratory viruses (RSV, HPIV, influenza virus, coronavirus, and rhinovirus) could remain viable for hours or even days.

 

Under the right conditions, enteric viruses - like Rotavirus, Norovirus, and Hepatitis A - have been known to survive on fomites from weeks to months.

 

We live in a germy world. 

 

Which is why public health agencies and organizations push hand washing so vigorously.  They know it literally saves lives.

 

As an inveterate hand washer from way back (I was a paramedic during the 1970s, before wearing latex gloves became de rigueur), I’m certainly a believer.

 

I had my hands in an untold number of unspeakable messes, but washed (well . . actually scrubbed) my hands more than a dozen times each day, and managed to stay healthy.

 

For more on all of this I’d invite you to visit:

 

 http://www.globalhandwashingday.org/

 

And the CDC’s hand hygiene website, where you will find many resources, including a link to a new iPad/iPhone application called iScrub.

 

»» Read More

Giving Germs A Helping Hand

 

 

 

# 5892

 

One hundred and sixty-three years ago, a Hungarian physician named Ignaz Semmelweis published a controversial medical book called Etiology, Concept and Prophylaxis of Childbed Fever.

 

At the time, childbed - or puerperal fever - was a common cause of mortality and morbidity among postpartum women. Semmelweis demonstrated that it could be greatly reduced by simply having doctors wash their hands before performing gynecological exams.

 

Sure, that makes sense today, but at the time his theories were considered radical (Pasteur wouldn’t come up with his `germ theory’ for another 17 years).

 

Besides, it was outrageous to suggest that doctors might actually be causing disease and death among their patients.

 

Semmelweis was ridiculed, ostracized and eventually forced to leave his hospital post. He died at the age of 47 in an asylum, a broken man.

 

More than 160 years later, infection control professionals continue to drum the message of proper hand hygiene into HCWs (Health Care Workers), yet lapses remain common.

 

A discouraging report from the Irish Independent.

 

 

Doctors 'worst' at basic hand hygiene

By Eilish O'Regan Health Correspondent

Wednesday October 12 2011

Nearly one in four doctors fails to clean their hands between patients -- increasing the risk of passing on potentially life-threatening infection, a damning report revealed yesterday.

 

The survey of hand hygiene in 36 acute hospitals revealed that doctors were the worst offenders (61pc) and that, overall, nearly three in 10 staff were not following the basic rule of infection control.

(Continue . . .)

 

  
The actual audit report is available on the HPSC (Health Protection Surveillance Center) website.

 

June 2011: Hand Hygiene Audit Results (Period 1)

File Size: (278kB)
Publication Date: 11 October 2011

Frequently Asked Questions on Hand Hygiene Audit Results

File Size: (167kB)
Publication Date: 11 October 2011

 

The `good news’ is that nurses – who likely have the greatest direct contact with patients – were the best at hand hygiene, with a compliance rate of just over 80%.

 

 

The `bad news’ is that this survey may not accurately reflect the level of compliance when auditors are not present.   The report explains:

 

 

3.  Limitations of Auditing Hand Hygiene with Direct Observation 

The results may not be reflective of healthcare worker compliance at all times. Compliance with hand hygiene is measured by auditors observing healthcare workers undertaking patient care. It is well recognised that workers will change their behaviour, if aware that they are being observed (Hawthorne effect).

 

However, it is also known that this effect wears off over time and that healthcare workers under observation may not be aware (due to the many competing demands on their attention) of the presence of the auditor. In addition, the purpose of auditing is to improve practice, therefore any action that improves compliance increases patient safety. Auditors are requested to give immediate feedback to ward staff following an audit, thereby increasing awareness and knowledge of hand hygiene. 

 

While overall compliance was just under 75%, the goal is to raise that to 90% by 2013.

 

Given the heavy burden of HAIs (Hospital Acquired Infections), on May 5th of this year the World Health Organization promoted a CLEAN YOUR HANDS DAY  to encourage HCWs to improve and sustain hand hygiene practices around the world.

 

 

Clean Care is Safer Care

First Global Patient Safety Challenge
Clean Care is Safer Care

The goal of Clean Care is Safer Care is to ensure that infection control is acknowledged universally as a solid and essential basis towards patient safety and supports the reduction of health care-associated infections and their consequences.

 

As a global campaign to improve hand hygiene among health-care workers, SAVE LIVES: Clean Your Hands is a major component of Clean Care is Safer Care. It advocates the need to improve and sustain hand hygiene practices of health-care workers at the right times and in the right way to help reduce the spread of potentially life-threatening infections in health-care facilities.

• Find out more about SAVE LIVES: Clean Your Hands
• More about Clean Care is Safer Care
• The Clean Care is Safer Care team

Below you’ll find some resources from the WHO, including posters, PDF files, and articles.

Five Moments for Hand Hygiene

The newly developed Five Moments for Hand Hygiene has emerged from the WHO Guidelines on Hand Hygiene in Health Care (Advanced Draft) to add value to any hand hygiene improvement strategy. Quite simply, it defines the key moments for hand hygiene, overcoming misleading language and complicated descriptions. It presents a unified vision and promotes a strong sense of ownership.

 

Not only does the Five Moments align with the evidence base concerning the spread of HAI but it is interwoven with the natural workflow of care and is designed to be easy to learn, logical and applicable in a wide range of settings. Find out more about your Five Moments by clicking the links below.

 

Whether you work in a healthcare setting or not, today would be a good day to visit the CDC’s hand hygiene website, where you will find many resources, including a link to a new iPad/iPhone application called iScrub.

 

To round out this entry, some oldies but goodies from the AFD archives.

 

Doing The Hand Jive

Hand Hygiene Among Doctors Exposed

Gonna Wash Those Germs Right Off Of My Hands

 

And finally a collection of Hand Washing posters can be found at:

 

Suitable For Framing

»» Read More

Study: Respiratory Viruses & Air Re-Circulation In Cars

 

 

 

# 5460

 

 

Two weeks ago a neighbor with a raging upper respiratory infection called me from the hospital Emergency Room and asked if I’d pick him up and take him home. 

 

A reasonable enough request, so I agreed.  But I did take a couple of precautions.

 

I brought a surgical mask for my coughing passenger to wear, and I drove him the five miles home with the windows rolled down.

 

Turns out, not only did I not catch whatever bug my neighbor had, according from a new study out of Australia, my instincts were right as well.

 

We don’t have a published study (one may show up eventually), but we do have a news report from 9NEWS on a presentation made to the Thoracic Society of Australia and New Zealand Annual Scientific Meeting in Perth this week.

 

The study compared the air flow and recirculation of viruses between a late model automobile and an `old clunker’ from 1989, and concluded that the `air-tightness’ of new cars could increase the risks of contracting a respiratory virus from a fellow occupant.

Dr. Scott Bell, Director of Thoracic Medicine at the Prince Charles Hospital in Brisbane is quoted as saying:

 

"Put simply, if you are travelling for around 90 minutes in a relatively modern car with air circulation on low, you are almost certain to catch influenza from another infected passenger.

 

The key message is that high risk people should be cautious of who they travel with in passenger cars during outbreaks of influenza."

 

 

Running a newer automobile’s air conditioner with it’s ventilation set to high (not re-circulating) was the functional equivalent of driving with a window partly down, which sucked a large number of viral particle out of the vehicle.

 

While lacking somewhat in scientific detail, you can read the entire article at:

 

Old cars safer than new to avoid the flu

17:47 AEST Mon Apr 4 2011

Travelling in old "clunkers" rather than late-model cars could protect people from catching the flu, new medical research shows.

 

But of course, you don’t have to buy an old clunker for car pooling during flu season.  You can reduce your risks by simply remembering to roll down a window, or run the a/c or heat on high ventilation.

Turns out, your Mother was right, after all.

 

A little bit of fresh air is good for you.

»» Read More

Study: Longevity Of Viruses On PPEs

 

 

 

# 5449

 

 

 

PPEs – or personal protective equipment – are items worn by Health Care Workers (HCWs) when examining or caring for potentially contagious patients. They include masks, gloves, and gowns.

 

During the opening months of the 2009 pandemic, it became obvious that our world faced a shortage of PPEs, and so strategies were adopted to maximize their use.  

 

In some cases nurses were issued only one N95 mask to be used for an entire 8 hour shift, and told to don it only when in direct contact with a potentially infected patient. 

 

This, as you might imagine, raised concerns among HCWs that this strategy of reusing masks could expose them, and their patients, to the virus.  That, and the decision to issue surgical masks instead of N95s, sparked protests across the country.

 

Nurses Protest Lack Of PPE’s

Report: Nurses File Complaint Over Lack Of PPE

California Nurses Association Statement On Lack Of PPE

 

Unfortunately, there are differing opinions and gaps in our scientific knowledge regarding the relative effectiveness of N95 vs. surgical masks (something I’ve covered often, including here, here, and here) and on how long a virus may remain viable on inanimate objects (like masks & gloves).

 

Inanimate objects that can transfer infectious agents are called fomites, and the CDC’s  (very) short answer on how long viruses can remain viable on these surfaces reads:

 

How long can human influenza viruses remain viable on inanimate items (such as books and doorknobs)?

Studies have shown that human influenza viruses generally can survive on surfaces for between 2 and 8 hours.

 

Today we’ve a new study that looks specifically at how long viruses may remain viable on PPEs. It appears in the Japanese journal Environmental Health and Preventative Medicine  (Hat tip Tetano on FluTrackers).

 

Essentially, researchers inoculated various fomites (masks, gloves, gowns, wooden and steel desktops) with laboratory grown H1N1, and then tested the surfaces after 1, 8, and 24 hrs for the presence of the virus (HA titer & 50% tissue culture infective dose (TCID₅₀)/mL were measured).

 

Environmental Health and Preventive Medicine

Volume 15, Number 6, 344-349, DOI: 10.1007/s12199-010-0149-y

Maintenance of influenza virus infectivity on the surfaces of personal protective equipment and clothing used in healthcare settings

Hiroko Sakaguchi, Koji Wada, Jitsuo Kajioka, Mayumi Watanabe, Ryuichi Nakano, Tatsuko Hirose, Hiroshi Ohta and Yoshiharu Aizawa

ABSTRACT (Excerpt)

Results 

The HA titer of this influenza A virus did not decrease in any of the materials tested even after 24 h. The infectivity of influenza A virus measured by TCID₅₀ was maintained for 8 h on the surface of all materials, with the exception of the rubber glove for which virus infectivity was maintained for 24 h.

Conclusions 

Our results indicate that the replacement/renewal of personal protective equipment and clothing by healthcare professionals in cases of exposure to secretions and droplets containing viruses spread by patients is an appropriate procedure to prevent cross-infection.

 

TCID₅₀ is the  amount of a pathogenic agent (in this case the H1N1 virus) required to infect 50% of cell cultures inoculated.

 

The results indicate that all surfaces tested harbored viable H1N1 viruses for at least 8 hours, with some surfaces infectious for more than 24 hours.

 

These test results extend the window of infectivity from fomites considerably beyond what has previously been reported.

 

The debate over the proper use of PPEs, and just how protective they really are, is a contentious one.

 

During a highly virulent disease outbreak, getting the science right (and applying it) could save a lot of lives.  We were very lucky that the CFR (case fatality ratio) of the 2009 pandemic was as low as it was. 

 

Last January the IOM (Institute of Medicine) released, through the National Academies Press, an extensive, 200+ page update on the use of PPEs (personal protective equipment) for healthcare workers when facing pandemic influenza and other viral respiratory illnesses.

 

The short version is, we need better science upon which to make decisions regarding the right kind of protection for HCWs.

 

While the entire 200 page pre-publication pdf can be downloaded for free, you can also view an executive summary and an abbreviated list of recommendations.

 

 

While this study from the EHPM won’t close the book on fomite transmission - it does add to our knowledge of the subject – and it shows us just how hearty influenza viruses can be, even outside of a host.

 

For more on the debate over PPEs you may wish to review:

 

Why Size Matters

Study: Aerosolized Transmission Of Influenza

NPI’s and Influenza

NEJM Perspective: Respiratory Protection For HCWs

»» Read More

APIC Calls For Mandatory Flu Vaccination For HCWs

 

 

# 5282

 

 

APIC (the Association for Professionals in Infection Control and Epidemiology, Inc.) has joined the chorus of other professional infection control and medical organizations (including SHEA, IDSA, & AAP) who are calling for mandatory yearly flu vaccinations for healthcare workers (HCWs).

 

If this story sounds a bit like Deja Flu, you probably recall that in October of 2008 APIC released a similar statement (see APIC Seeking Mandatory Flu Shot For HCWs), but in that case provided for an informed `opt out clause’ if HCWs signed a declination form saying they understood the risks to patients.

 

The new statement eliminates that escape clause, recommending that that hospitals, nursing homes, and other facilities employing HCWs:

 

“require influenza immunization as a condition of employment unless there are compelling medical contraindications."

 

You can read the entire 4-page position paper, outlining their recommendations and rationale behind them, on the APIC home page.

 

APIC Position Paper:  Influenza Vaccination Should Be a Condition of Employment for Healthcare Personnel, Unless Medically Contraindicated

 

The paper also calls for those who are exempted for medical reasons to:

 

“. . .  be educated on the importance of careful adherence to all of the non-vaccine related HICPAC prevention strategies, including hand hygiene and cough etiquette.

Further, they may be  required to wear a surgical mask when contact with patients or susceptible employees is likely. “ 

 

Over the past year several other professional medical organizations have made similar calls for mandatory vaccinations.

 

AAP: Recommends Mandatory Flu Vaccinations For HCWs

SHEA: Mandatory Vaccination Of Health Care Workers

IDSA Urges Mandatory Flu Vaccinations For Healthcare Workers

 

While strongly advocating HCW influenza vaccination, the CDC has stopped short of mandating them. I blogged on this back on June 23rd, 2010  in  CDC: Proposed Influenza Infection Control Guidance.

 

Similarly, a UK Department of Health report issued in June 2010 called Learning The Lessons From the H1N1 Vaccination Campaign For Healthcare Workers  – while not mandating vaccination – stresses the `professional duty’ of all HCWs to get the vaccine.

 

New York State attempted to require vaccination as a requirement to work as a HCW in 2009, but legal challenges and vaccine shortages forced them to abandon – at least temporarily – that mandate  (see New York Rescinds Mandatory Flu Shots For HCWs).

 

While many infection control experts see this as a long overdue step in patient and co-worker protection, the obstacles that lay before these sorts of policies are substantial.

 

This is a hugely divisive issue, with many HCWs believing that it is an infringement of their rights to decide what will be injected into their bodies.

 

There will almost certainly be legal challenges, and possibly labor disputes as well. I’ve covered HCW’s objections to forced flu shots in the past, including:

 

HCWs: Refusing To Bare Arms

HCWs: Developing a Different Kind Of Resistance

 

 

Only a few large hospitals have thus far managed to implement mandatory flu vaccinations, including Seattle’s Virginia Mason Medical Center and BJC Heathcare of St. Louis, Missouri  which I blogged about here

.

Details on how Virginia Mason Medical Center implemented mandatory HCW vaccinations can be read in the following  PDF.

 

 

Over the past 5 years Virginia Mason MC has maintained a 98% vaccination rate, and has vigorously promoted the uptake of flu shots not only in the workplace, but the greater community as well.

 

An abstract from a study that appeared in the August 2010 Infection Control and Hospital Epidemiology journal concludes that a policy of mandatory HCW vaccination is feasible, sustainable, and effective.

 

DOI: 10.1086/656210

Mandatory Influenza Vaccination of Healthcare Workers: A 5‐Year Study

Robert M. Rakita, MD; Beverly A. Hagar, BSN, COHNS; Patricia Crome, MN; Joyce K. Lammert, MD, PhD

(EXCERPT)

Results.

In the first year of the program, there were a total of 4,703 HCWs, of whom 4,588 (97.6%) were vaccinated, and influenza vaccination rates of more than 98% were sustained over the subsequent 4 years of our study. Less than 0.7% of HCWs were granted an accommodation for medical or religious reasons and were required to wear a mask at work during influenza season, and less than 0.2% of HCWs refused vaccination and left Virginia Mason Medical Center.

 

Impressive results. 

 

And, when combined with increased calls from infection control organizations to adopt similar practices, likely to inspire other facilities to follow suit.

»» Read More

CMAJ: Infectious Risks In Family Doctor’s Offices

 

 

# 5165

 

 

I didn’t used to be a germaphobe.

 

In fact, as a paramedic in the 1970s, I worked without gloves 99% of the time (everyone did) - had my hands in some truly awful messes - and hardly gave it a second thought.  

 

A vigorous application of Betadine scrub (fingertips up to the elbows) was the universal cure-all after every call.

 

Of course, this was before HIV, MRSA, and Hepatitis became threats.

 

Looking back at those days, the lackadaisical attitude over infection control in hospitals, ambulances, and yes . . .  even the morgue  . . .  seems reckless and difficult to fathom now.

 

Fast forward almost (ahem) 40 years, and I now carry a little bottle of alcohol sanitizer in my car, and often in my pocket, where ever I go.  I cringe at the thought of sitting in a crowded doctor’s waiting room, and I wash my hands at least 10 times a day.

 

I even keep some surgical masks and exam gloves in a baggie in my car (and in both of my first aid kits), just in case I’m called upon to help out in a car wreck or other emergency.

 

I admit, I’m somewhat more germ conscious after having read Maryn McKenna’s superb Superbug: The Fatal Menace of MRSA, but I can’t place all the blame on her. Penning over 5,000 blogs on infectious diseases over the past five years has no doubt had an effect, as well.

 

And for awhile, during the pandemic, it seemed that many in the general public shared my, err . .  fastidiousness (a much nicer word than `mania’) about hand hygiene and cough and sneeze etiquette.

 

Doctor’s offices routinely handed out surgical masks in the waiting room for those with respiratory symptoms.  Big bottles of hand sanitizer sat on every desk, and signs were everywhere to stay home if you were sick.

 

But the pandemic is now gone, and so are most of those little bottles of hand sanitizer. 

 

Many of the hygienic practices taken by the public – and in doctor’s offices – last year, have slowly eroded, or have slipped out of use entirely.

 

And according to an article that appears in the CMAJ this week, that is a big mistake. 

 

Follow the link to read:

 

December 20, 2010

 

Infectious risks in family doctor’s offices

 

Although the value of hand washing in the prevention of influenza is debatable (see The Flaw In The Ointment  and Sanitized For Your Protection ) there is no doubt that good hand hygiene and respiratory etiquette can significantly reduce the spread of many illnesses.

 

Recently a study appeared in  BMC Infectious Diseases, which suggests hand hygiene can be effective even against the `common cold’.

 

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

 

 

The bottom line to the CMAJ article is that infection control policies and procedures not only belong in acute care settings - like hospitals and ambulances – they also need to be reinforced, and maintained, in doctor’s offices as well.

 

Otherwise, we risk letting a lot of preventable illnesses slip through our fingers.

»» Read More

Ontario: A Top Ten List Of Infectious Disease Threats

 

 

 

# 5146

 

From a joint study between the Institute for Clinical Evaluative Sciences (ICES) and the Ontario Agency for Health Protection and Promotion (OAHPP) we’ve a study that looks at the relative societal impacts of various infectious diseases in Ontario, Canada.

 

I suspect you  may find their `top ten’ list a little surprising.

 

First an excerpt from their press release, then links to an 8 page summary document, and a link to the full 198 page study.

 

Nearly 5,000 Ontarians die from infectious diseases every year

The Ontario Burden of Infectious Disease Study (ONBOIDS) finds many of top 10 are often overlooked

TORONTO, Dec. 14 /CNW/ - Nearly 5,000 Ontarians die from infectious diseases every year. Many of these infectious diseases get little recognition in terms of public awareness, media attention and resource allocation, says a new study released by the Ontario Agency for Health Protection and Promotion (OAHPP) and the Institute for Clinical Evaluative Sciences (ICES).

 

Led by Dr. Jeff Kwong, scientist at ICES, and Dr. Natasha Crowcroft, director of surveillance and epidemiology at OAHPP, ONBOIDS is the most comprehensive review of the burden of infectious disease in Ontario to date. The study reviewed data on 51 different infectious diseases to determine their impact on the life and health of Ontarians.

 

The ten most burdensome infectious diseases in Ontario are:

• Hepatitis C virus
• Streptococcus pneumoniae
• Human papillomavirus (HPV)
• Hepatitis B virus
• Escherichia coli (E. coli)
• Human immunodeficiency virus (HIV/AIDS)
• Staphylococcus aureus
• Influenza
• Clostridium difficile
• Rhinoviruses (common cold)

"Each year, Ontarians seek medical attention for more than seven million episodes of infectious diseases. Infectious diseases are not going away, and we as a society need to realize the impact of a number of these diseases," says Dr. Kwong. 

(Continue . . .)

 

Please click here to read the summary report, or here for the full report.

 

 

These reports used Ontario mortality statistics from 2003 to 2005, and illness statistics from 2005 to 2007.  

There are a few surprises here, including the ranking of human papillomavirus (HPV) as the infectious disease with the third highest impact.

 

Hepatitis C and B ranked higher than I suspect many would have expected as well, but the authors suggest that provinces with fewer immigrants might see lower rates of those diseases.

 

And it is notable that a number of these diseases (MRSA, Clostridium difficile, Streptococcus pneumoniae) are often contracted as hospital acquired infections (HAIs), highlighting the need for better infection control procedures.

 

Other regions of the world, with dissimilar climates, population demographics, and international travel and immigration patterns would no doubt see a different ordering of their top ten list, with some of these pathogens dropping off, and others moving up.

 

But for Ontario, and presumably other provinces in Canada, this study should help officials decide where best to put their public health resources.

 

Going back to the press release, one of the authors sums it up this way:

 

"It is important to remember that infectious diseases are preventable in many different ways. These findings show where and how we should be concentrating our efforts to get the greatest impact in improving the health of Ontarians. Improvements range from concentrating on immunization programs where vaccinations exist, such as for human papillomavirus, through increasing screening and access to treatment for hepatitis B and C, to developing new ways to fight infectious diseases," says Dr. Crowcroft.

 

 

My thanks to Shiloh on FluTrackers for the link that led me to these reports.

»» Read More

CDC Finalizes Flu Infection Control Guidance

 

 

# 4920

 

 

Earlier this summer the CDC published their proposed Flu Infection Control Guidance, soliciting comments and recommendations from interested parties (see CDC: Proposed Influenza Infection Control Guidance).

 

Two major concerns of HCWs (Health Care Workers) was the issue of whether flu shots should be mandatory, and a decision on what type of mask (surgical or N95 respirator) should be used for routine care of flu cases.

 

Despite calls from several major Infectious disease organizations (IDSA, SHEA, AAP), the CDC stopped short of recommending that flu shots be mandatory for HCWs.

 

Surgical masks were deemed appropriate for routine care of flu patients, although N95s are still recommended for certain higher risk procedures.

 

Rather than re-invent the wheel, I’ll simply provide you with a link to the new guidance, and refer you to Lisa Schnirring’s excellent coverage at CIDRAP.

 

 

CDC finalizes flu prevention guidance for health settings

Lisa Schnirring Staff Writer

Sep 20, 2010 (CIDRAP News) – The US Centers for Disease Control and Prevention (CDC) recently issued new guidance for preventing flu in healthcare settings that reflects a year's worth of new information about the 2009 H1N1 virus and recommends surgical masks rather than N-95 respirators when providing routine care for flu patients.

(Continue . . .)

 

 

»» Read More

Another Mask Study To Ponder

 

 

# 4853

 

 

Long-time readers of this blog are aware of a number of conflicting studies that have come out in recent years regarding the relative efficacy of surgical masks and N95 respirators in protecting HCWs (Health Care Workers) against airborne infections.

 

 

For decades, the assumption was that only properly fitted N95 masks protected the wearer, and that surgical masks were worn by HCWs to protect the patient during invasive procedures.

N-95 Respirator         Surgical Facemask

 

Last year, during the summer outbreak of pandemic H1N1, many hospitals citing shortages of N95 masks, opted to equip their nurses with surgical masks instead. 

 

This went against the recommended infection control guidelines issued by the CDC at the time, but was supported by several major infectious disease professional organizations.

 

This resulted in numerous protests last fall by nurses and other care givers, as I reported in:

 

CNA/NNOC Plan Protest Over Inadequate H1N1 Protection

 

(Photo from CNA/NNOC Webpage)

 

Since then, we’ve seen several `semi-reassuring’ studies that suggested that surgical masks are acceptable protection.

 

In October the NEJM published a perspective article (see NEJM Perspective: Respiratory Protection For HCWs) based on the recent IOM evaluation of surgical masks vs. respirators, and reiterated the advice:

 

Until more data are available, the committee recommends that clinicians reach for the N95 respirator when confronting patients with influenza-like illnesses, particularly in enclosed spaces.

 

A few days later JAMA (Journal of the American Medical Association) published a study which reported that HCWs using surgical masks experienced `noninferior rates of laboratory-confirmed influenza’.

In March of this year, we saw the following study (see Study: Efficacy of Facemasks Vs. Respirators).

 

 

Study finds surgical masks provided effective protection of health-care workers against H1N1

The effectiveness of ordinary surgical masks as opposed to respirators in protecting health care workers against the 2009 H1N1 influenza virus has been the subject of debate. An observational study published in the April 1, 2010 issue of Clinical Infectious Diseases, available online, suggests that surgical masks are just as effective as respirators in this regard.

 

 

The evidence over the winter, it seemed, was largely supportive of the notion that surgical masks were adequate protection against influenza viruses.

 

So in June of this year, the CDC released revised infection control guidance proposals which relaxed their previous recommendations to the allowing of surgical masks for routine care, and reserving N95 masks for aerosol producing procedures (intubation, suctioning, etc).

 

CDC: Proposed Influenza Infection Control Guidance

 

To complicate matters, however - after these studies suggested that surgical masks are reasonably protective against influenza - we now get a new study that questions whether surgical masks or N95 respirators provide any substantial protection to the wearer at all.

 

No . . .  I don’t make these things up.  I just report on them.

 

The study appears in the September issue of the AJIC (American Journal of Infection Control), and is titled:

 

Quantifying exposure risk: Surgical masks and respirators

Keith T. Diaz, MD, Gerald C. Smaldone, MD, PhD

 

These researchers (using mannequins fitted with a variety of masks, and using radiolabeled wet aerosols) determined that wearing surgical masks and N95 masks without an airtight (Vaseline) seal provided little more protection than wearing no mask at all.

 

They did find that placing a surgical mask on an infected source (patient) could significantly reduce the spread of a virus to the environment.

 

Since only the abstract is freely available, it is helpful that the SurgiStrategies website has posted a summary of these findings.  

 

A hat tip to Tetano on FluTrackers for passing along this link.

 

 

AJIC Releases New Study on Face Masks and H1N1

 

The authors of this review quote the researchers as stating the type of mask (N95 vs Surgical) “does not play a significant role in reducing exposure to the recipient unless a respirator is physically sealed to the face of the source."

 

 

While obviously not the last word on the subject, the issue of just how protective various types of masks are to the wearer has just gotten a bit more murky.

 

Obviously, we will await the next mask efficacy study with considerable interest. In the meantime, I guess I’d better check my supply of Vaseline.

»» Read More