Showing posts with label nosocomial infection. Show all posts
Showing posts with label nosocomial infection. Show all posts

Thursday, September 11, 2008

EPA BASE study suggests HVAC plays a role in Sick Building Syndrome

A newly released analysis of the US EPA BASE study shows that improperly maintained HVAC systems may cause symptoms associated with Sick Building Syndrome (SBS). The study's authors (representing Lawrence Berkeley, Harvard University, Helsinki University and the US EPA) assessed data collected from 97 representative US office buildings that use air conditioning.
The findings that interested us most dealt with SBS symptoms that may be attributed to moisture with the HVAC systems. From the study's abstract (text emphasis added by me):
"Humidification systems with poor condition/maintenance were associated with significantly increased upper respiratory symptoms, eye symptoms, fatigue/difficulty concentrating, and skin symptoms, with OR = 1.5, 1.5, 1.7, and 1.6. Less frequent cleaning of cooling coils and drain pans was associated with significantly increased eye symptoms and headache, with OR = 1.7 and 1.6. Symptoms may be due to microbial exposures from poorly maintained ventilation systems and to greater levels of vehicular pollutants at air intakes nearer the ground level. Replication and explanation of these findings is needed."
Also from the study's Discussion section:
"These findings support current beliefs that moisture-related HVAC components such as cooling coils and humidification systems, when poorly maintained, may be sources of contaminants that cause adverse health effects in occupants, even if we cannot yet identify or measure the causal exposures."
Limitations
The authors caution that these findings need replication before suggestions or guidelines are advocated. While researchers were able to quantify the risks associated with poorly maintained humidification systems, they were unable to "...identify important (symptom) benefits from well-maintained humidification systems."

The study's findings are important because they demonstrate and elevate the need for Ultraviolet Germicidal Irradiation (UVGI) in all air conditioned buildings. Our experience has shown that if you have dirty or inefficient cooling coils, your HVAC is likely a reservoir for microorganisms. These microorganisms can cause symptoms associated with SBS, in hospitals these pathogens can promote Hospital Acquired Infections (HAI).

This study is a small but important piece in the puzzle that surrounds Indoor Air Quality. Its importance lies in the fact that yet another credible group of scientists have found evidence that HVAC systems can be linked to airborne pathogens that cause health problems.

Thursday, August 28, 2008

Learn Something New Everyday

I learned something new today about the Center for Medicare and Medicaid Services' (CMMS) plan to change reimbursement for some Hospital Acquired Infections (HAI). The new item appears in the Consumers Reports Blog:

"Medicare has listed eight preventable conditions (above) for which it will not reimburse hospitals after Oct. 1, 2008, and is proposing nine more conditions to be added in 2009. The effects could widen as private insurers and state-funded health insurance programs begin to follow Medicare's lead.

Some of the eight have been dubbed "never events" because they should never happen. They include leaving sponges or implements in a patient after surgery and giving the wrong type of blood. Several hospital-acquired infections are also on the list. In 2007, almost 500,000 hospitalized Medicare patients were hurt by the eight preventable events.

While the new rule bars hospitals from passing the bill on to the patient, it addresses only charges accrued in the initial hospital stay. But patients might need continuing treatment that adds up to a bundle. Consumers Union has asked Medicare to clarify that patients who are harmed by these preventable conditions will not be billed for any of the additional care they need."

I didn't realize that the continuing costs of treatment following a hospital acquired condition were not addressed by the legislation. So...stay tuned. When Consumers Reports dot Org receives an update, I will pass it on.

Monday, June 30, 2008

MRSA deep clean a waste? Not really.

The headline blared, PATIENTS STILL AT RISK FROM MRSA DESPITE 57 MILLION POUND DEEP CLEAN'. The entire premise, I thought, was so bizarre. The idea that a one-time cleaning of something would prevent the return of contamination. If this was true, my 5 year old son would be overjoyed. He could take a bath in June and be set for the entire summer.
MRSA infection is a complex problem that is not to be eradicated with a one shot effort. Simple solutions, those sometimes promoted by press and politicians, are part of the answer, but not the entire answer. Maybe that's because staph bugs don't read the newspaper or listen to political speeches. Otherwise they would know to completely leave the hospital and never return following the 'deep clean'.
The headline in question appeared in the UK's Independent, written by Brian Brady and Jane Merrick:
Thousands of patients will remain at risk from superbugs, despite a £57m "deep clean" of hundreds of hospitals, because a vital screening programme will not be put in place for at least a year.
One of the world's leading experts on hospital-acquired infections (HAIs) warned yesterday that every one of the hospitals cleaned under Gordon Brown's flagship health policy will be back to square one as soon as the cleaners finish, because no one is stopping bacteria such as MRSA and Clostridium difficile from coming into the buildings.
Professor Hugh Pennington of Aberdeen University said the deep-clean programme would be "an expensive waste of resources".
The thought that a one time deep cleaning would end Hospital acquired Infections is naive at best, dangerous at worst. Professor Pennington' s assertion that MRSA infections are not "...environmental..." depends on what your definition of environmental is.
"Professor Pennington said: "Politicians get hung up on cleaning, but the major issue isn't environmental; it is people bringing the bugs into hospitals. Once the bacteria hit the floor they die off. The natural home of MRSA is either in infected patients or up the noses of the rest of us, so that is what they should be attacking."
At VIGILAIR we stress that all infections are environmental. A good example of MRSA as an environmental pathogen
is found in an article published in the journal of the Hospital infection Society-- 'Ventilation grilles as a potential source of methicillin-resistant Staphylococcus aureus causing an outbreak in an orthopaedic ward at a district general hospital', (1998) 39: I 27-I 33).
This article showed how MRSA was being distributed in a hospital via the ventilation system. While it is true that most MRSA is introduced into the hospital by visitors, patients and staff, environmental controls are key in removing these pathogens from the environment. Pennington's statement that MRSA bacteria die when they hit the floor is contradicted by a large body of research. The November 2006 issue of Infection Control and Hospital Epidemiology contains a report on MRSA survival that is typical of this research:
"We examined the duration of survival of 2 strains of methicillin-resistant Staphylococcus aureus (MRSA) on 3 types of hospital fomites. MRSA survived for 11 days on a plastic patient chart, more than 12 days on a laminated tabletop, and 9 days on a cloth curtain."
Ignoring the care environment in the fight against MRSA is short sighted. The strategy that we recommend acknowledges that the environment plays a significant role in hospital acquired infection and that several tactics must be employed together to be successful.
We've been able to culture Staph from the cooling coils of hospital HVAC units. Psuedomonas, Staph and many other bacteria are taken from patient care areas, and then find an excellent breeding ground in the dark, cool and food rich home in hospital ventilation systems.
VIGILAIR technology removes the HVAC as a reservoir for pathogens by disinfecting the HVAC system. VIGILAIR UVGI deactivates bacteria, fungi and viruses on surfaces as well as in the air. Importantly, this protection is constant.
Unlike one time cleanings the germicidal irradiation of cooling coils continues 24 hours a day, VIGILAIR technology is no silver bullet, either. It must be used in tandem with hand washing and 'deep cleaning'. The combination of these efforts is the best way to remove these pathogens. Any one of these tactics used in isolation will provide only a temporary relief, because hospital acquired infections are environmental by nature.

Thursday, June 05, 2008

MRSA Action UK-They Get it!

Over on our other site we highlighted a new report on anti-bacterial wipes yesterday. This morning we see that MRSA Action UK agrees with our sentiments:

MRSA Action UK: Antibacterial wipes are not the panacea for healthcare infections

Wednesday, 04 Jun 2008 08:46
MRSA Action UK’s contention has always been that to eliminate bacteria from the healthcare environment a systematic, comprehensive policy of eradication must be employed. In today’s medical arena the battle against infections is not just against MRSA and Clostridium difficile, but also against the others waiting in the wings. As a Charity that has been campaigning for safer hospitals in this country all the initiatives that have been introduced to reduce infections in our hospitals will fail, if this systematic and comprehensive approach is not taken.

Hospital cleanliness is paramount for the safety of patients in the NHS, and using antibacterial wipes as a policy to keep our hospitals clean is doomed to failure.

Antibacterial wipes can be effective against pathogens such as MRSA but only if used in the right way. They should only be used once for one surface, however there is no substitute for proper cleaning and decontamination performed by staff that are properly educated and trained in this process, using the appropriate equipment and techniques. The cleaning process should be comprehensive, and we believe monitored on its efficacy, and compliant in all ways. To be successful in this decontamination process it must be supported by regular environmental testing.

Controlling the infections in our hospitals cannot be solved by any single method, there are many ways for these pathogens to be transmitted on hands, uniforms, contaminated equipment and by the airborne route. The abject failure of this government to introduce a comprehensive system of infection prevention and control has ensured that as a nation we will stay bottom of the league with the numbers of healthcare infections in our hospitals, and until they tackle this problem head-on we will not have the safe, clean care of our neighbours in Northern Europe, where eradication of the bacteria remains a top priority.

As a Charity we have always maintained that whilst antibacterial wipes may help to prevent a patient contracting a healthcare infection, they are no guarantee, only thorough regular decontamination, and strict adherence to comprehensive infection prevention and control policies will do this.


Derek Butler
Chair
MRSA Action UK
Registered Charity No. 1115672
Telephone: 07762 741114
http://mrsaactionuk.net

Eureka! They really get it.

Wednesday, May 07, 2008

Pilot study reinforces use of portable anteroom HEPA filtration

A new study from a leader in airborne disease research indicates that Operating Room HEPA filtration is not a guarantee against nosocomial infection. Dr. Russel Olmstead led a team that looked at airborne contamination inside of the OR environment.

Pilot study reinforces use of portable anteroom HEPA filtration

To prevent perioperative transmission of airborne microorganisms

Washington, DC, May 6, 2008 – Amidst an increase in new tuberculosis cases, researchers have begun investigating the effectiveness of new operating room filtration systems designed to protect staff and patients. According to pilot study findings published in the May issue of the American Journal of Infection Control, a supplemental portable anteroom high-efficiency particulate air (PAS- HEPA) filter unit placed outside operating room suites may prevent secondary transmission of airborne microorganisms like Mycobacterium tuberculosis (M. tuberculosis).

“The rate of decline in newly reported tuberculosis cases in the U.S. has slowed,” said lead study investigator Russell N. Olmsted, MPH, CIC, epidemiologist from Saint Joseph Mercy Hospital in Ann Arbor, MI. “This, coupled with the worldwide emergence of even more drug-resistant tuberculosis, reinforces the need for renewed vigilance and surveillance from healthcare professionals. In particular, study results reinforce the need for measures to optimize air particle removal.”

Olmsted and colleagues compared the efficiency of freestanding HEPA filtration units to a new portable anteroom system (PAS)-HEPA combination unit in removing harmful airborne infectious pathogens. Freestanding HEPA units were evaluated in the operating room, while the PAS-HEPA unit was placed outside over the main operating room door. Both smoke plume and non-infectious particles similar in size to M. tuberculosis were used to mimic movement of airborne pathogens within highly pressured environments.

“We observed interruption of normal patterns of airflow with freestanding HEPA units placed inside the operating room,” said Olmsted, adding that instead of being captured by the air-filtration system, smoke plume traveled upward from the operating room table and into the breathing zone of personnel who might be present during a typical surgical procedure.

“This suggests an increased potential for occupational exposure to airborne microorganisms as well as an unwanted introduction of contaminants into the patient’s open surgical site,” he explained.

In contrast, deployment of the PAS-HEPA combination unit pulled the smoke downward, away from the operating room table and toward the floor and main door. The second phase of the study (which involved simulated microscopic particles) mirrored these observations; within 20 minutes, over 94% of submicron particles were cleared from the operating room.

“The results of Mr. Olmsted’s study reinforce the Centers for Disease Control and Prevention (CDC) 2003 guidelines for environmental infection control as well as 2005 guidelines for preventing the transmission of M. tuberculosis in healthcare settings,” said Janet E. Frain, RN, CIC, CPHQ, CPHRM, APIC 2008 President and Director, Integrated Services, Sutter Medical Center in Sacramento, CA. “These findings should be considered for integration into an overall infection prevention and control program to help ensure both patient and healthcare personnel safety.”


These findings substantiate results we've discovered in our testing of Operating Rooms. Recently we found microbial contamination (including fungi) immediately downstream from HEPA filtration units installed in ORs. The contamination was found one week after the filters were certified for efficiency compliance.
Filters are great for trapping microorganisms, but they do not 'kill'. Eventually filters can become colonized and act as a breeding ground for pathogens. Thinking that you have 100% protection because you have HEPA filtration is a false sense of security.
We suggest a balance between UV and filtration to provide a better strategy for reducing environmental pathogens in critical care areas of your hospital. E-mail us to find out more about a recent study in which VIGILAIR provided better protection than laminar flow for operating suites in a large urban hospital.

Hospitals struck by new killer bug | Metro.co.uk

UK Newspaper continue to examine (and exploit) news on infectious disease. The latest cause for concern is Stenotrophomonas, nick-named 'Steno' for popular consumption.

Hospitals struck by new killer bug | Metro.co.uk

Tuesday, May 6, 2008

A new hospital superbug resistant to all antibiotics could be killing hundreds of patients, experts have warned.

The infection, known as 'Steno', is on the increase and could be harder to tackle than MRSA and C.difficile.

The bug spreads almost exclusively in hospitals through wet areas such as taps and shower heads, and is thought to kill a third of the people it infects after entering the bloodstream.

Chemotherapy patients, including children, are among those most in danger, because the infection spreads through ventilation tubes and catheters.

There are about 1,000 reports of Steno blood poisoning in Britain each year, according to today's study by the Wellcome Trust Sanger Institute, near Cambridge.

Research leader Dr Matthew Avison said: 'This is the latest in an ever-increasing list of antibiotic-resistant hospital superbugs.

'The degree of resistance it shows is very worrying. Strains are now emerging that are resistant to all available antibiotics.'

MRSA is thought to have caused 1,652 deaths in 2006, up from 51 in 1993. Clostridium difficile was mentioned on 6,480 death certificates in 2006, a 72 per cent rise on 2005.

Steno sticks to catheters or medical tubes and grows into a so-called 'biofilm'. When the catheter is next flushed, the bug enters the patient's bloodstream and can cause septicaemia, especially if their immune system has already been weakened.

The onus is on both patients and healthcare professionals to do more to keep equipment clean, Dr Avison told the Genome Biology journal.


Stenotrophomonas is another pathogen that we've isolated from the hospital environment. In our study, we were able to culture Stenotrophomonas from surfaces in the Heating Ventilation and Air Conditioning (HVAC), surfaces in NICU as well as in the tracheal aspirates of the patients. As mentioned in the article, this bug likes water--and that is where we found it, in the water of the HVAC drain pan.

As we look to decrease Hospital Acquired Infections (HAI), we should consider all the reservoirs for pathogens. Neutralizing the source of an infectious agent is the key to long term success in infection prevention. Is the Stenotrophomonas in the HVAC water making its way into the care areas? It's hard to say and expensive to prove.

So, we focus a lot of attention on 'end of the pipe' solutions such as hand washing. This is a good thing. But at the same time we should eradicate the factories where pathogens are generated and distributed within a health care facility. Our research has shown that one such factory is the HVAC system. We've also shown that VIGILAIR® can eliminate this reservoir as a potential source.

Wednesday, April 02, 2008

Doctors Frustrated over Acinetobacter Infections

All the healthcare professionals that I know are good hearted people with a great capacity for compassion and a desire to heal. Doctors are, at heart, 'fixers'. So you can understand the frustration infection control professionals feel when they run out of treatment options. Consider the plight of physicians dealing with drug resistant Acinetobacter, as referenced in this article fron the UK's Telegraph:

"Pandemic fear over resistant superbug

By Stephen Adams
Last Updated: 2:20am BST 02/04/2008

Doctors have warned that if a superbug which is known to be even more resistant to antibiotics than clostridium difficile and MRSA takes hold in hospitals, the country could face a pandemic.

The acinetobacter bug is being treated with older antibiotics because newer ones do not work. There are fears that injured soldiers returning from Iraq and Afghanistan have passed the infection on in civilian hospitals.

Prof Matthew Falagas, an expert in hospital-acquired infections, said: "In some cases, we have simply run out of treatments and we could be facing a pandemic with public health implications."

He warned delegates at the Society for General Microbiology conference in Edinburgh: "Doctors in many countries have gone back to using old antibiotics that were abandoned 20 years ago because their toxic side-effects were so frequent and so bad.

"But superbugs like acinetobacter have challenged doctors all over the world by becoming resistant to these older medicines.

"Even Colistin, an antibiotic discovered 60 years ago, has recently been used. But now it occasionally fails as the bacteria has become resistant."

There are more than 1,000 reports of acinetobacter infections every year in the UK, according to the Health Protection Agency (HPA). Some strains can cause death through blood poisoning and pneumonia."


Acinetobacter is particularly difficult to remove from the environment of care because it is hearty and can survive for nearly a month in dry conditions. Healthcare providers will do their best to fight this bacterium, but turning back the clock to use older antibiotics is not a good long term strategy.

Because Acinetobacter has been proven to be transmitted via the air in several hospital studies, it is prudent to consider that the airborne route of transmission may play a role. While UVGI systems designed by VIGILAIR can help reduce environmental contamination, they are not a silver bullet. Like antibiotics, VIGILAIR is one part of a multi-faceted infection control strategy. VIGILAIR's strength lies in its ability to eliminate environmental reservoirs where microorganisms proliferate.

A VIGILAIR white paper on Acinetobacter is available here.

Wednesday, March 26, 2008

Nosocomial Infections, the next Rainmaker for Personal Injury Attorneys?

If you live where I do, you'd think that Personal Injury (PI) attorneys are doing quite well for themselves. They dominate the media here, pitching their services on TV, radio, billboards, bus benches, etc. While medical malpractice is a staple for attorneys, we now see an effort to find clients who've suffered from a Hospital Acquired Infection (HAI). Here's an example of PI marketing targeting nosocomial infections:

"Hospitals Are Profiting From Their Mistakes at Our Expense | Colorado Personal Injury Lawyers

In no other business that I know of, can you turn a profit when you sell a defective product or service. If the television set you purchased at your local electronics store doesn’t work when you get home, you take it back to the store and get a refund or exchange. When the mechanic doesn’t repair the brakes on your car properly, you don’t pay him until they’re fixed. If the bread you buy at the grocery store is moldy you take it back and get fresh loaf.

Back what if you can’t take it back? What if there are no exchanges? Suppose you go to the hospital and they cut off the wrong limb or operate on the wrong body part. You can’t take that back. You can’t get an exchange. What if not only did the hospital provided inferior care but charged you for it as well? It happens all the time at hospitals all over the United States.

An article in the Journal of American Medical Association focuses on a common but mostly preventable medical error, urinary tract infections associated with the use of a catheter. In a perverse twist, the hospitals are actually rewarded for bad care.

Urinary catheters are the most commonly used medical devices in hospitals, and account for approximately one million infections annually. That’s 40 percent of all hospital-acquired infections. A urinary tract infection can add a day to a hospital stay; and it can lead to a more serious infection and even death.

(snip)

“All too often, clinicians, hospitals, and payers conclude that some harms are part of the price of doing business. But in many cases they are not,” write Dr. Wald and Dr. Kramer. “When properly designed, financial incentives should provide rewards for desired clinical outcomes, not hospital-acquired harms.’”

Not rewarding hospitals for inferior care? All I can say is, it’s about time!"

Will HAI litigation be the next rain maker for PI lawyers? Before attorneys start the assault, they would be wise to consult epidemiologists. While many HAI can be prevented, proving negligence on the part of a hospital may prove elusive. Take a recent study from the American Journal of Infection Control(1) in which researchers looked at a database of more than 1,500 documented nosocomial outbreaks, with an eye on finding the source of the infection.

I mention this because I would think that attorneys must find the source or cause of a HAI in order to punish the responsible party. Among the findings: the source of the pathogen was unknown for a significant proportion of the outbreaks. Below are outbreak pathogens, followed by the percentage of times their source in an outbreak could not be determined:

Pathogen
Source of pathogen outbreak not known (%)
Staphylococci 43.5%
Pseudomonas 37.2%
Klebsiella 58.3%
Acinetobacter 36.2%
Serratia 31.9%

Clearly, the study has limitations, but if anything it is biased in favor of outbreaks that have a reported source, as those are more likely to be the subject of a published study.

Consider MRSA. According to the CDC, in 2005:

"Approximately 18,650 persons died during a hospital stay related to these serious MRSA infections.

Serious MRSA disease is still predominantly related to exposures to healthcare delivery:

  • About 85% of all invasive MRSA infections were associated with healthcare, and of those, about two-thirds occurred outside of the hospital, while about one third occurred during hospitalization.
  • About 14% of all the infections occurred in persons without obvious exposures to healthcare."

Trying pointing the finger of blame at a hospital when two-thirds of the MRSA appears to be contracted in the community and then brought into the hospital. Who do you sue?

The bit that I understand about epidemiology tells me that in regards to litigation over HAI, large paydays are not in the cards for PI attorneys. Even with all our diagnostic tools, it is expensive and labor intensive to prove empirically that this bug caused that infection and can from this place. Not impossible, but PI lawyers are going to go where the easy money is. Hospitals are likely to defend themselves with credible medical experts who will educate jurors that infections involve microbiology, epidemiology and the physical environment. Modeling these diverse disciplines is science and art.

Having said the above, I would image that the threat of lawsuits will have more of an impact on healthcare. When you couple that threat and impending regulation changes in reimbursement, hospital administrators are doing the right thing and trying to reduce HAI. Our product, VIGILAIR, is on an excellent resource to help them achieve that goal.

I would be remiss if I didn't comment on the attorney article that opened this piece. The author says that consumers should not pay for services with a negative outcome. I wish all attorneys worked on this premise.


1. Gastmeier, S. Stamm-Balderjahn, S. Hansen, I. Zuschneid, D. Sohr, M. Behnke, R. Vonberg, H. Rüden. Where should one search when confronted with outbreaks of nosocomial infection?. American Journal of Infection Control, Volume 34, Issue 9, Pages 603-605 P.

Wednesday, March 12, 2008

Study: MRSA Screening Fails to Lower Infection Rates

A new study published in the Journal of the American Medical Association says that universal MRSA screening upon admission to a hospital may not lead to fewer MRSA infections. The study compared two sets of surgery patients who received services at a Swiss hospital.

One group of more than 10,000 patients were screened for MRSA prior to surgery. If they tested positive for MRSA they were isolated and treated with disinfectant and antibiotics. The control group was of similar size and was not screened. Results from the study show no significant differences in the infection rates between the two groups.

From the Chicago Tribune:

"This is what we've been saying all long," said Kathy Warye, chief executive officer of the Association for Professionals in Infection Control and Epidemiology, a group that opposes efforts to mandate MRSA testing.

While screening patients can be a valuable, it's not a "magic wand" and it's not always the best way to deploy a medical institution's resources, said Dr. Stephen Weber, director of infection control at the University of Chicago Hospitals

Critics of the report's findings say the study may've overlooked some pre-existing MRSA reservoirs:

"Dr. Barry Farr, a MRSA expert, noted the Swiss hospital didn't screen patients on medical wards, who probably served as a reservoir of MRSA infections within the institution and skewed the study's results.

About one-third of surgery patients at the Swiss hospital had surgery before measures could be taken to control potential MRSA infections; that may have contributed to the findings, said Dr. Karen Kaul, chair of molecular pathology at Evanston Northwestern Healthcare."

Responses from both sides (pro and con) augment a central argument in VIGILAIR's infection control (IC) strategy.

  • We believe that IC is dynamic and multifaceted
  • There is no one strategy to eliminate infection
  • There are many reservoirs of infection including patients, healthcare workers and the environment
  • A prudent IC policy attacks pathogen reservoirs on several fronts simultaneously; bundling strategies works best

So, Now What?

MRSA screening has resulted in significant benefit for other facilities, notably Scandinavian hospitals that have virtually eliminated nosocomial MRSA infection after implementing 100% screening upon admission. This new study is not enough justification for a wholesale discrediting of MRSA screening. It is, however, more evidence that IC is more like a web than a chain. Breaking one link of transmission rarely does the trick.

Thursday, February 14, 2008

Killer in the NICU

From my adopted college town of Manchester, the sad story of a NICU death likely caused by airborne aspergillus:

"Baby ward hit by fatal infection
A Greater Manchester hospital has temporarily closed its neo-natal unit after a baby died and another suffered a potentially fatal infection.

A premature baby developed an infection from aspergillus, a common airborne fungus, and died in December at Salford Royal Hospital.

A second pre-term baby tested positive for skin aspergillus last week.

The hospital said it had closed the ward as a precaution to establish any "common contributory factors".

The aspergillus fungus is very common and can be found in homes and buildings everywhere, but can cause infections."

Many studies have shown that aspergillus is ubiquitous in the environment. Healthy people can be exposed to it without serious consequences. That is not true for immune compromised patients in ICU areas. So, what to do about it?

How about filtering the air? Hospitals already do that and yet aspergillus persists. How about letting in more fresh air? This strategy will introduce more and potentially different types of aspergillus into the hospital. What about cleaning the HVAC frequently to get rid of pathogens?

Studies have shown that traditional cleaning is not effective, as this report(1) from the ECMM shows:

"It appears that fungal spores are not necessarily removed by cleaning the fans. Even scratching and painting them, to eliminate rust and restore a smooth surface on which fungal spores cannot be retained, does not permit decontamination."

In fact, servicing the HVAC can exacerbate the problem(2):

"Our observations suggest that localized, short-term exposures resulting from disturbance of (aspergillus) reservoirs are comparable to or may even greatly exceed maximum expected routine exposures. Further, these reservoirs may be disturbed not just during construction or renovation, but even during routine maintenance activities (telecommunications cabling, HVAC filter replacement) that require access to ceiling spaces."

It is clear that the unique needs of ICU areas need unique solutions. That's where VIGILAIR® comes in. VIGILAIR® Systems combine filtration and the germicidal effect of UVC. Rather than just trapping aspergillus spores, VIGILAIR® is designed to provide enough UVC exposure (dose) to destroy aspergillus. UV technology disinfects HVAC surfaces and then keeps those areas clean by continuously radiating the reservoirs where microorganisms can thrive.

Once again, we need to be aware than Infection Control is an environmental issue. Diligent IC professionals must recognize and remove all reservoirs for pathogen growth within the hospital. Unfortunately, the HVAC system is frequently overlooked as a reservoir despite the fact that it houses the largest untreated water supply within a health care facility.

1. European Confederation of Medical Mycology Conference 1996. S. Heinemann, G. Van. houte, N. Nolard. Contamination of indoor environment and air conditioning.
2. European Confederation of Medical Mycology Conference 2008. Khan M, Gonsoulin T, Simpson S, Horner WE. Exposure levels of aspergillus fumigatus from various indoor reservoirs in health care facilities.

Friday, February 08, 2008

Echos in the media

It is encouraging to see response from the press over the recent report on hand washing and infection control. The argument that infection control is dynamic and environmental is being heard in the media, and from APIC! See the recent article from US News and World Reports:

Wringing Our Hands Over Infection Control

February 07, 2008 05:19 PM ET | Avery Comarow |
A number of thoughtful comments arrived concerning my January 23 hand-washing post, about a study showing that a much-increased rate of hand-washing is no guarantee that a hospital's infection rate will budge, let alone dive. A couple of correspondents (notably anesthesiologist-blogger Counting Sheep and hospital-CEO-blogger Paul Levy of "Running a Hospital") contributed thoughts that might prevent a few infections here and there.


The following came as a real letter, if also as an E-mail attachment, from Kathy Warye, another CEO. She runs the Association for Professionals in Infection Control and Epidemiology, whose obvious interest in this subject makes her note very welcome.


"Mr. Comarow makes a critical point that even the single most effective intervention (in this instance, hand hygiene) alone can't solve the problem of healthcare-associated infections. Certainly, even the best hand hygiene compliance only gets us so far.

Lessons learned from our 12,000 members who manage infection prevention programs in healthcare facilities around the world tell us that to reduce the risk of infection and protect people coming into hospitals means adopting a full range of strategies. The first step, from a facility-wide perspective, is conducting a proper risk assessment. Good infection prevention and control professionals don't just know their patients—they know their hospital, they know which areas are at high risk and where there may be hidden reservoirs of bacteria, be it the ER or the OR.


System-wide adoption of proper hand hygiene, contact precautions including use of gloves and gowns, and the "checklist" for device-related care that is receiving so much attention of late are among the tools known to be effective in preventing healthcare-associated infections."


Amen! The single largest source of untreated water in any hospital is its HVAC system. For Critical Care Units aerving the most immune compromised patients, we must eliminate the HVAC as a reservior for pathogens. While VIGILAIR is not a panacea, neither is washing hands. Our technology needs to complement other technologies and institutional efforts for infection control.

Tuesday, January 29, 2008

Hand washing just one part of infection control, medical experts say

An excellent common sense approach to the hype surrounding hand washing hygiene. This article is excerpted from the Grand Island Independent, a newspaper published in Nebraska:


"Widespread use of antibacterial hand gels has helped make it easier for healthcare workers to comply with hand hygiene policies, which is especially important during cold and flu season.

The gels, which have been proven as effective at killing germs as soap and water, are also less drying to the skin an important quality for those who work in the medical field and may cleanse their hands up to 50 times per day.

Recent studies and local experience have proven, however, that increasing compliance to hand-washing policies is not always enough to reduce the rates of hospital-acquired infections.

A study published by the University of Nebraska Medical Center this month showed that while use of antibacterial hand gels in two UNMC adult intensive care units helped the units increase their hand-washing rate from 38 percent to 70 percent, there was no corresponding reduction in hospital-acquired infections.

But a similar experiment at St. Francis Medical Center has had different results.

At St. Francis, the use of hand sanitizer and the creation of a hand hygiene improvement committee has nearly doubled the rate of hand-washing policy compliance for the entire hospital, said Laura Mader, St. Francis infection control coordinator.

The hospital's current 76 percent compliance rate is above the national average. It has also led to a decrease in St. Francis' incidence of hospital-acquired infections, Mader said.

While UNMC and St. Francis had different results in similar experiments, officials from both facilities agree that hand washing, while highly important, is only one component of infection control.

"There are many factors that influence the development of hospital-acquired infection," said Dr. Mark Rupp, professor of infectious diseases at UNMC. "It would be naive to think that a single, simple intervention would fix this problem."

The lack of a correlation between increased hand hygiene and lower incidence of infections could be attributed to many factors, including UNMC's already low infection rate in the ICU."

Infection Control professionals fight disease transmission on many fronts. While hand washing has drawn much attention, it is merely one weapon in the arsenal. We believe that a comprehensive approach to infection control should include air disinfection, especially in critical care units.

Wednesday, January 23, 2008

Reporting Live From AHR EXPO 2008

The AHR Expo is in full swing here in New York City. We are among 1,800 exhibitors that are presenting booths at this show. The technical programs have been outstanding, especially the programs dealing with Ultraviolet light.
As a whole the industry seems to be maturing. As compared to previous years when people asked, “What is UV?”, this year they know what it can do and are asking more questions regarding applications. The field of UV manufacturers is well represented here at the Expo and at the technical committee level. Although we are competitors there is an agreement that we have shared interests as an industry.
This spirit was evident at a symposium entitled, ‘Applying UV Without Getting Burned’. Moderated by Steve Martin, the forum discussed the safety implications of applying UV to HVAC. Altru V’s VP of Technology Dave Witham demonstrated how his company is testing the effects of UV on HVAC components such as filters, insulation and wiring. His company has created a testing chamber to help quantify those effects.
Richard Vincent, the author of many journal articles on UVGI, also touched upon the safety aspects of applying UV. Dr. Vincent is a recognized expert in the field and discussed the conclusions of a 7 year study on the effects of UV in homeless shelters.
The always entertaining Dave Marciniak of the GSA round-out the forum. His use of humor livened the sometimes dry details of government safety guidelines and regulations. Being the last speak in a forum is always tough but Dave did it with memorable style. My kind of bureaucrat!
Another highlight was a presentation made by Kathryn Worrilow Ph.D of Leigh Valley Hospital. Her talk was part of the TC 2.9 (thanks for the update, Mr. Bahnfleth) series, AKA Control of Infectious Diseases with UVGI. Dr. Worrilow, an embryologist, explained how the use of UVGI air disinfection led to better clinical outcomes in her lab. Her study, The Impact of UVC Radiation on Clinical Pregnancy and Miscarriage Rates in ISO 5 Cleanroom In Vitro Fertilization Laboratory was well received and is the latest in a growing body of evidence linking UV air sanitation with positive clinical outcomes.
Among the contacts VIGILAIR made at AHR is Ponkamon Aumpansub, a graduate student at Penn State. Her studies at the prestigious Penn State Indoor Environment Center deal with the complex issues surrounding the modeling and mitigation of contaminants in large buildings. AHR is first and foremost an expo to promote business. It is also important to recognize that tomorrow innovations will come from today’s engineering students such as Ms. Aumpansub. It is imparative for commercial entities to foster the relationship between research and commercial applications as their goals are connected.
The theme that seemed to resonate throughout the 1,800 exhibits this year is the emerging importance of IAQ in all aspects of HVAC. There is an awareness from front line mechanical contractors to multi-national manufacturers that HVAC is all about creating an environment of comfort and safety indoors. VIGILAIR and our partners at Steril-Aire are at the vanguard of implementing UV to meet those goals.

Wednesday, January 16, 2008

Hand washing no panacea

I was delighted to hear the ABC song drifting from my bathroom last night.  It meant that my five year old son was following the instructions he learned in school to properly guage the amount of time he should wash his hands with soap and water.  Will he do this everytime? Probably not, but it is important to try.

The situation in my house is much like the situation in many healthcare facilities, according to an LA Tines article on the MRSA Watch blog site:

30 studies show hand washing neglect

Link: Beating the staph superbug - Los Angeles Times.

But, with a few exceptions, hospitals and public agencies have been slow to gear up against MRSA. More than 30 studies have shown, for example, that healthcare workers wash their hands about half as often as they're supposed to, even though washing before and after seeing each patient would drastically cut down on infection rates. Hospital surfaces and equipment aren't cleaned as often as they should be, and careless habits -- like touching potentially contaminated surfaces after hands have been washed but before touching the patient -- contribute to the spread. The first order of business should be to get a clear picture of MRSA. Where is it and how prevalent? An upcoming bill by state Sen. Elaine Alquist (D-Santa Clara) would make MRSA a reportable disease and require hospitals and nursing homes to report their infection rates. In Tennessee, which tracks MRSA, it quickly became the third most common reportable disease in the state, behind chlamydia and gonorrhea. A similar bill was vetoed in 2004 by Gov. Arnold Schwarzenegger, but the recent news from the CDC should make him rethink his position, despite the almost certain opposition of hospitals.

http://tahilla.typepad.com/mrsawatch/2008/01/30-studies-show.html

I bring this to your attention to demonstrate that infection control is dynamic.  There is no silver bullet.  Infection control requires multi-layers and some redundancies.  Our technology, VIGILAIR®, does not replace other sanitary efforts--it complements and enhances them.  Like hand washing, VIGILAIR® is not a cure all.  It is a prudent and effective way to reduce the airborne environmental pathogens within your facility.

Wednesday, January 09, 2008

Brits love a healthy debate...

From Britain's Telegraph, news on a new government program to reduce antibiotic prescriptions as a way to reduce the superbug cycle. I've included a snippet of the article. It is the responses to the article that are just as interesting. In response to this topic, readers blame doctors, politicians and patients for the problem. These comments show the complexity of the issue and the passion of those seeking a solution. My favorite response is listed below in which the writer tells people to stop being wimps, suck it up and go to the doctor's office less.

Stop giving antibiotics for colds, doctors told


By Rebecca Smith, Medical Editor
Last Updated: 12:09pm GMT 09/01/2008

Doctors are to be told to stop prescribing antibiotics for coughs, colds and sore throats because over-use of the drugs is fuelling the spread of killer hospital superbugs.

  • Alan Johnson, the Health Secretary, says it is time to end the unnecessary use of penicillin and other commonly-prescribed pills, which cost the NHS £1.7 billion a year.

    Using antibiotics too liberally has led to bugs such as MRSA becoming resistant to treatment with the drugs. Most colds, coughs and flu are caused by viruses, which cannot be treated with antibiotics anyway, Mr Johnson points out.

    Announcing a £270 million campaign against superbugs, to be launched next month, he says it is vital that doctors adopt "less of a knee-jerk reaction to prescribing".

    The campaign, called Clean, Safe Care, will also include an extra £45 million for hospitals to spend on infection control nurses or antibiotic specialist pharmacists. All patients going into hospital will be screened for MRSA by 2009.

  • COMMENTS:

    Antibiotics fight "bugs", not viruses, so the basic premise is absolutely correct. Do not give antibiotics merely for colds or flu. BUT post viral conditions such as chest infection, infected sinuses and catarrh (and real sore throats) DO need antibiotics and I hope this will not change under the new guidelines. Perhaps doctors could prescribe a placebo antibiotic to anyone insisting on antibiotics who merely has a viral infection.
    Posted by graham wagner on January 9, 2008 9:59 AM


    Antibiotics are not the cure for superbugs, cleanliness is - and the hospitals simply aren't clean enough in the UK. Accountability is needed, not money, run a hospital like a fast food joint. "Clean as you go" and it is all staff's responsibilty to clean up, not delegated to the lowest bidder.
    Posted by Craig Douglas on January 9, 2008 9:55 AM

    So what is Alan Johnson's next big idea? Now wash your hands? Make sure you're wearing your face-mask? Or is he going to go round every surgery and tell the doctors what medicine to prescribe? What a joke! The trouble is this joker is in charge of the health service! That is more frightening than any superbug.
    Posted by Pinkie on January 9, 2008 9:27 AM

    The best solution for colds and viruses is to stop giving them to everyone else!
    If people stayed at home and looked after themselves when they became ill there would be a lot less general illness in the community, rather than battling on and infecting all and sundry.
    Surely we all know by now that antibiotics are not given out by GPs for colds - that has been common knowledge for decades - hence the barrage of cold 'cures' on the shelves.
    Posted by Annie on January 9, 2008 9:25 AM

    I am a GP and we know that we should not give antibiotics in the circumstances described; the patients do not always know this and it does not matter how many times we inform them they will keep coming back until they get them, in these circumstances another approach needs to be adopted and a debate needs to be taken on what this might be.
    Posted by Jonathan Allcock on January 9, 2008 8:50 AM

    Simple - don't go to your doctor - it's dangerous. I've been telling my patients this for years. The whole ludicrous thing is compounded by several factors: the great unwashed believe it's their god given right to be ill on a regular basis, a health service that is free at the point of delivery (if you offer free beer there's a queue that stretches round the corner and up the road), and a partially educated, disinterested and overpaid workforce.
    Posted by Andrew Renaut, Associate Professor of Surgery, Brisbane on January 9, 2008 8:36 AM

    The crux of the issue lies in the fact that many people are greedy and want immediate satisfaction. I have wrestled with people who demanded antibiotics for simple viral illnesses. The the patient wants to leave with something in his/her pocket and they are willing to go to any means to acquire it.
    There are also legal implications that are caused by the system. If a patient complains of not receiving the desired medication or a rationalized "standard of care", the legal system automatically demonizes the medical practitioner.
    I am all for placebo's in this instance.
    Posted by James on January 9, 2008 7:51 AM


    Yes suck it up. It is called illness. We are made of flesh and blood and mortal. It is normal for people to get sick off and on. You must endure illness sometime. If you find yourself going to the doc everytime you feel unwell then you likely are a mental case ie "nervous nelly". Anxiety /depression are a big reason why folks can't cope w/ minor illnesses. Quick being a wimp
    Posted by ER doc on January 9, 2008 6:59 AM


    Again the real cause of hospital infection is ignored. Unsustainable bed occupancy ratios, and out- sourcing of hospital cleaning. Blaming GPs is an irrelevant political ploy. Fight the real battle please.
    Posted by John Powell on January 9, 2008 6:47 AM


    Most experts talk around the Problem of Antibiotic Resistance. Your article headlines should say "ALL COLDS ARE VIRUSES, ANTIBIOTICS DO NOT KILL VIRUSES, THEREFORE YOU(DOCTORS) MUST NOT USE/ ANTIBIOTICS and start from there. Bacteria and viruses are as different as Gold and Lead. It is possible that a virus can make a person sick and that because of a compromised Immune System bacterial Infections can follow which can then require antibiotics to heal, It should also be pointed out that antibiotics tend to kill many neccessary bacterial species in the body and so lead to further problems-(example,life on the toilet) and Candida infections
    Posted by declan mansfield on January 9, 2008 6:13 AM


    Source: http://www.telegraph.co.uk/news/main.jhtml?xml=/news/2008/01/09/nbiotic109.xml

    Wednesday, October 24, 2007

    More Evidence of MRSA's Airborne Spread

    Epidemiologists are like medical detectives. They analyze an outbreak and then use their knowledge and tools to identify the outbreak source. Below is an excellent study from the Medical School in Kitakyushu, Japan. The study took place in a hospital area that housed 37 patients recovering from head and neck surgery. Three patients in single occupancy rooms became infected with MRSA after surgery.
    Were all three patients colonized by the same strain of MRSA? If so, what was the source and how could patients in three separate rooms become infected with the same pathogen?
    Researchers used air sampling machines and surface swabs to collect MRSA samples. Then the samples were analyzed using polymerase chain reaction and pulsed-field gel electrophoresis. The result?
    "An epidemiological study demonstrated that clinical isolates of MRSA in our ward were of one origin and that the isolates from the air and from inanimate environments were identical to the MRSA strains that caused infection or colonization in the inpatients."
    The conclusions of this study indicate that disinfecting the air circulated within their ward could help reduce colonization of patients (bold emphasis added by me).

    "In this study, we confirmed that MRSA could be acquired by medical staff and patients through airborne transmission. The findings suggest the importance of protecting patients against cross-infectious agents existing in aerosols. Although measures for prevention and control of nosocomial infection with MRSA include handwashing with an antimicrobial agent; wearing a gown, gloves, and a mask; and removing MRSA from the nasal vestibule, few measures have been established to control airborne bacteria. Laminar unidirectional airflow, air ventilation, and air filtration could also be beneficial in hospital environments and should be considered. Further studies will be needed to assess the levels of MRSA contamination of air and to develop more effective means of controlling and removing airborne MRSA."

    Once again we see that there is no silver bullet for infection control. Disease transmission is not all contact, nor is it all airborne, rather it is a dynamic combination of many things. In this hospital ward, airborne transmission took on increased importance because the patients in this care unit lack typical host defense mechanisms in their upper respiratory tracts.
    VIGILAIR® systems are proven to reduce pathogen load within the air stream by destroying microorganisms with UVGI, and removing the microorganisms with filtration. You may download the research article in its entirety here.

    Reference:
    Teruo Shiomori, MD, PhD; Hiroshi Miyamoto, MD, PhD; Kazumi Makishima, MD, PhD. Significance of Airborne Transmission of Methicillin-Resistant Staphylococcus aureus in an Otolaryngology–Head and Neck Surgery Unit. Arch Otolaryngol Head Neck Surg. 2001;127:644-648

    Thursday, August 23, 2007

    UK University Leeds the way in Airborne Infection Research

    Some of the most compelling and important research in airborne contamination control originates from a progressive university in the resilient city of Leeds. Known as a manufacturing center (or is it centre?), Leeds has managed to diversify itself, evolving into a hub for international banking and business services.

    Researchers at the University of Leeds are proving that hospital design plays a major role in healthcare, specifically the growing problem of hospital acquired infections. Perhaps the key to their success is an understanding of the role that the indoor environment plays in disease transmission. According to Leeds professor Andrew Sleigh, “There is evidence that 10 to 20% of infections are spread through the air, but until now, their role in the infection chain has been largely overlooked, as doctors tend to emphasise the importance of washing hands and avoiding physical contact.” I guess being open to new ideas can lead to new discoveries.

    Another key could be the University’s cross-disciplinary approach to learning. Leeds University prides itself on innovative study programs that give students creative options:

    “Many of its research initiatives cross traditional subject boundaries and Leeds currently promotes projects through 58 inter-disciplinary centres and seven research schools.”

    This approach is apparent in the Pathogen Control Engineering Research Group within Leeds’ School of Civil Engineering:

    "Our multi-discipline approach brings together investigators from a variety of backgrounds including public health engineering , fluid mechanics , building services engineering and microbiology . This has produced a team with the all-round strengths required to undertake rigorous research in the field of aerobiology and indoor air quality.

    Leeds’ advances demonstrate both the challenge and the promise of airborne infection research. Research in this field requires the talents and intelligence of participants from several disciplines. This approach was taken by scientists who reviewed research papers published between 1960 and 2005 on airborne disease transmission (1). More than 200 papers were assessed by a team of 15 experts in epidemiology, virology, environmental health and engineering. This study, and the work at Leeds, shows that greatest discoveries are found at the nexus of divergent technologies.

    Recent Leeds Research

    Although not entirely complete, Leeds researchers released some results from recent airborne pathogen testing. According to Professor Sleigh's research, infectious particles are distributed within hospital wards.

    “Although diseases such as tuberculosis are widely accepted as being airborne, others may also be spread this way. Numerous bacteria-carrying particles - such as tiny flakes of human skin - can be widely dispersed into the air within hospital wards through routine activities, and potentially contribute to the risk of infection for patients.”

    PhD students Abigail Hathway and Katherine Roberts used a laser counter to assess the particle concentration of hospital ward air. Their data indicate that normal staff operations such as making rounds, closing drapes and changing patient beds significantly affected concentrations of airborne particles.

    These findings add important new insight to the role of the airborne route in infection transmission. This research will be used by the UK’s National Health Service to update guidelines for ventilation and infection control. According to Ms. Hathaway, more research will be done in the upcoming months, with an eye on possible publication in 2008.

    Diverse curriculum, public-academic partnerships and accomplished professors are among the reasons why Leeds attracts more undergraduate applications than any other UK university. Plus, any school that Mark Knopfler attended has got to be way cool!

    1. Li Y, et al. Role of ventilation in airborne transmission of infectious agents in the built environment—a multidisciplinary systematic review. Indoor Air 2007; 17: 2-18.

    Wednesday, August 22, 2007

    Best of the web

    Keeping track on how states are dealing with legislation on Hospital Acquired Infection reporting? Then check out this blog:
    About Health Transparency
    You can easily see the status of legislation that mandates the reporting of quality measures. While you're there, you may find the 'Cost Measures' link interesting. You can see the disparity in costs/payments for various procedures in several communities. As far as I can tell, the site is a public/private partnership that is legit, not a shell shill for an industry group.

    Monday, May 21, 2007

    Taking the fight against hospital acquired MRSA into your own hands

    Think of it as a ‘Do it Yourself’ kit for preventing hospital acquired infections (HAI). The kit is a collection of disinfecting wipes, hand rubs and other products designed to prevent patients from catching a bug while they’re in the hospital.

    The “PatientPak’ is marketed in the UK for about $43. The web site for the product is long on promises short on specifics (www.patientpak.com). Consider this text from the company’s press release:

    The PatientPak Hand Sanitiser and Sanitising Wipes are the only products available that are tested and proven to kill and clean away MRSA and at least 99.999% of all bacteria, including dangerous viruses, Norovirus and Bird Flu. Combining a cleaning detergent and bacteria-killing disinfectant in one, harmful bacteria are killed in just 10 seconds. PatientPak’s Hand Sanitiser and Sanitising Wipes, the most extensively tested products on the market, are also the only MRSA-killing products that are hand safe with just 5% alcohol, meaning that food can be eaten after application with no need to re-wash hands.”

    Maybe I’m reading this wrong, but the first sentence indicates that viruses are a subset of bacteria (see bold text). A quick scan of the web site reveals no corroborating case studies or published data on germicidal efficacy. If the products are indeed the most, “…extensively tested…” shouldn’t the test results be available?

    I’d like to know how the sellers know that the products ‘kill’ bird flu? Was it tested against H5N1, or was it a surrogate? Or does it work against Influenza A, and therefore it is assumed to likely be effective against bird flu?

    I’m also sceptical of the germicidal effects of a detergent that is used for 10 seconds. To the best of my knowledge, detergents do not ‘kill’ or deactivate microorganisms. Detergents help water remove and dilute contaminants. It is generally accepted that washing your hands with a detergent (soap) requires a good 20 seconds or so. I may be wrong, but since the company does not provide an explanation of their technology or other scientific studies, we are forced to use the information that we have.

    On the positive side, I like the idea of empowering people to actively participate in their healthcare. Bringing the PatientPak to the hospital is not necessarily a sign that a hospital is not doing its job. To me it is an indication that HAIs are environmental issues requiring a broad-based strategy. While hospitals need to do more, I wouldn’t bet my life on it.

    So, would I buy the PatientPak? No, not based upon what I know of the kit so far. I do not believe, however, that it will cause any harm. It might actually help. There’s a lot of sizzle in this product promotion, but not much science. It is always wise to remember that there are no panaceas for HAI.

    Monday, February 26, 2007

    Healthcare takes a new look at airborne pathogens


    The concept of airborne disease transmission was well accepted in the early to mid 1900's. It was frequent that you would see UV lights in hospital wards for upper air disinfection. UV lights were a standard form of infection control in TB wards.
    But then times changed. Aggressive measures helped to eradicate TB from our country. Drugs such as vaccines proved effective and immediate. Hospitals, like all buildings, began to have ventilation to exhaust contaminated air while bringing in fresh air. Scientists and researchers turned away from studying airborne transmission and moved on to newer issues.
    Since the advent of SARS, pandemic influenza and a resurgence in TB, scientists are once again turning their attention to airborne transmission. We've prepared a new white paper that examines some of the findings of these new studies. Like all good research it answers some questions and raises some more! Hopefully this spark new interest in studying airborne transmission.