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By John Roark
Legionella pneumophila,Aspergillus fumigatus, and Clostridium difficile are on the most-wantedlist of airborne and waterborne pathogens. Will we ever really have themcontained?
Every healthcare facility is rife with ideal conditions forany number of airborne and waterborne pathogens. These bugs set up shop whereyou would expect to find them, and are stealthy enough to hide where they maynot be detected until the immuno-compromised patient succumbs to infection.
The Joint Commission on Accreditation of HealthcareOrganization (JCAHO)s 2005 Surveillance, Prevention and Control of Infectionstandards state that the prevention of healthcare-associated infections(HAIs) represents one of the major safety initiatives an organization canundertake, making the effective evaluation and possible redesign of existinginfection prevention and control programs a priority.
The Centers for Disease Control and Prevention (CDC) estimatesthat each year, approximately 2 million patients admitted to acute-carehospitals in the United States acquire infections that were not related to thecondition for which they were hospitalized. These infections result inapproximately 90,000 deaths, and add between $4.5 to $5.7 billion per yearto patient-care costs.1
Theres Something In the Air
Aspergillus, tuberculosis, SARS,gram negative bacteria and biological agents related to bioterrorism are part ofthe unending awareness in the fight against airborne pathogens. The CDCs Guidelines for Infection Control in Health-CareFacilities state that once these materials are brought indoors into ahealth-care facility by any of a number of vehicles (e.g., people, air currents,water, construction materials and equipment), the attendant microorganisms canproliferate in various indoor ecological niches and, if subsequently disbursedinto the air, serve as a source for airborne health-care-associated infections.2
As you look at hospitals, the focus needs to be placed onlooking at the risks of where these airborne and waterborne pathogens can enterand reside in healthcare systems, says Terri Rearick, RN, BS, CIC,administrator of safety services at Childrens Memorial Hospital in Chicago.Human reservoirs come to mind first. The challenge is to identify that thesereservoirs exist since people may be carrying airborne diseases as they enterthe healthcare system. The buildings of healthcare systems are organized in sucha way that the challenges of potential reservoirs of airborne organisms alsoexist in our ventilation systems, our water supplies and in our careenvironments.
The scrutiny of hospital design and the emphasis on locationof air intake, ventilation flow and exhaust play a vital role in containingthese pathogens. It all harkens back to tuberculosis, says Corinne Connor, RN,BSN, corporate manager for infection prevention and control, also at ChildrensMemorial Hospital. Back when tuberculosis was an even more endemic disease inthis country than it is now, managing the flow of patients was one of the thingsthat brought to the forefront the idea of how you get people into and out ofyour institution, what is the best way to capture their symptoms early and makesure they dont move forward through the rest of the facility. I think theadvent of negative air, and the whole idea of venting some areas directly to theoutside with filters to keep from re-circulating the bacteria also stems from theinitial studies of tuberculosis how we treat this and how we preventtransmission of it.
In years past, hospitals had infectious disease units withconcentrated populations of patients with suspected or diagnosed infections thatrequired isolation. The hospitals didnt have the design of todayshospitals in which the negative air pressure rooms, meant to contain airbornecontagious diseases, are scattered two or three on a unit, explains Rearick. This concentrated design of one given geographic settingwithin a hospital allowed for all patients who needed negative air pressureisolation, or other modified forms of isolation, to be placed in that one unit.This design served its purpose and may be reconsidered in the future dependingon the evolution of highly contagious communicable diseases.
In TBs heyday, hospitals had infectious disease unitsfocused in one given geographic area. I think it served the need at the time,since there were more diseases that required intense isolation, says Rearick.The availability and use of vaccines for such agents as measles, mumps,rubella, diphtheria, tetanus, pertussis, varicella, and other infectious agentshave altered the need for concentrated areas of negative air pressure rooms.
There was a purpose for the design, but, as years of vaccineuse have gone by, the needs have changed. Once again, people are starting tolook at alternate designs carefully as they design healthcare facilities withthe onset of SARS and other diseases that have airborne characteristics.
There are so many other diseases that have airbornetransmission characteristics that I think people are trying to prepare for thepossibility of needing to react to them in the future if they become endemic; ifnot epidemic, again, says Connor. Where theres an occasional patientwho comes into your facility with TB, were not going to be again dealing withdiseases where maybe 10 or 15 people will be coming in with the same type ofdisease. We will need to go back many decades in healthcare to revisit that mindset.
While some institutions are considering building completelyseparate infectious disease hospitals, others facilities consider thefeasibility of constructing infectious disease wards.
Hospital Resource and Services Administration (HRSA) hasrequested that hospitals develop a plan to isolate 500 patients per millionpopulation, says Andrew Streifel, MPH, a hospital environment specialist atthe University of Minnesota. According to the Office of Emergency Preparedness,designated hospitals should have 10 infectious disease beds per hospital and beable to handle pediatric or adult populations. This is something that is prettymuch a nationwide issue.
If You Build It, They Will Come
CDC guidelines state that environmental disturbances caused byconstruction and/or renovation and repair activities in and near healthcarefacilities markedly increase the airborne aspergillus spore counts inindoor air and increase the risk of nosocomial infection among high-risk patients.3
When you take old hospital buildings and start tearing intothem, youre going to uncover a lot of different critters that have been thereforever and ever, says John James, PhD, MPH, a microbial epidemiologist atChildrens Hospital of Denver. In most hospitals in America, there isconstant construction and remodeling, which causes problems when areas areopened and microbes are released, and you have to create containment systems. Wehave a very elaborate system of containment here you dont drive a nailinto the wall without my permission.
I go and see whats happening for any kind of remodeling orconstruction that goes on. You have to have a building permit and an infectioncontrol permit to do anything.
James inspects sites and examines barriers; for big projects, he is involved from the architectural stagethrough completion. Every step of the way, he says, he finds problems. When you go into these old areas, you find evidence of moldgrowth and water leaks from 50 years ago. If you didnt contain them, fungalspores and other microbes would be floating around, moving down hallways andgetting to immuno-compromised patients.
If you have dry building envelopes, and internal wallswhere there has never been water, you dont have much to worry about,continues James, but when you get water intrusion, the moisture plus theorganic materials in the dust act as nutrient for fungi, and you get growth. As long as you can keep it dry, you dont have any problem.But you cant keep any building completely dry. You get small leaks in waterpipes, or roof leaks, windows leak and water intrudes into the wall cavity.
Methicillin-resistant Staphylococcus aureus (MRSA)survives in the environment for weeks to months, says James. Its in dust.If you want to find MRSA, C. difficile or Vancomycinresistant Enterococci(VRE) in a hospital, you go to the corner of the room. The air movementconcentrates the dust in those corners, and the environmental services peoplehave a hard time cleaning out the little corners. Thats doesnt mean thatthats going to be a cause of infection for somebody, but you want to be asclean as you can. Dust control is very important in the hospital environment.
The legal liability related to indoor air quality inhealthcare settings is expansive, and the risk of construction-related infectionhas gained some media attention. In what ways are healthcare facilitiesvulnerable to liability?
A lot of it has to do with water damage and whether or notthey can provide performance criteria for their facility, says Streifel. Wewould like to build our facilities mold-free, as much as we can, but we knowgood and well that water damage occurs during construction you create acondition wherein if the climate is correct, you could have lots of mold damage.If the owner accepts that building in that condition and they putimmuno-compromised patients in there, youre going to have a problem.
In September 1992, a 55-year-old man underwent herniated discsurgery in a Massachusetts hospital. During the procedure, an airborne funguscontaminated the surgical site, which resulted in a disc space infection,complications of which lasted for nearly six months before doctors determinedthat the fungus had caused the infection. The plaintiff brought claims against ageneral contractor and sheet metal contractor who installed an air handlingsystem in the operating room, as well as claims against the environmentaltesting company that evaluated the OR suite after installation of the new airsystem. In addition, he filed claims against the hospital, the chairperson ofthe infection control committee and the infection control practitioner. The casesettled after more than four years of litigation. The contractors settled for a total of $117,000; the environmental testing company settled for a total of$150,000, and the medical defendants settled for a total of $450,000.4
What the problem was for that facility is they discoveredthe mold, says Streifel, who served as an expert witness on the case. Theyshut the fan down for several weeks during construction; they decided that they were going to test the environment tosee that it was appropriate for doing orthopedic surgery. They tested the airand found 650 colony-forming units of aspergillus fumigatus per cubicmeter of air it was the highest number I have ever seen inside of ahospital.
Weve got hospitals right now in this country that are 18to 20 months past occupancy because the construction was so shoddy that theyallowed water to come in around the flashing, the workmanship was very poor,scuppers failed, they drilled holes right through the stucco, brought water intothe inside of the building, continues Streifel. That intensive care unitwill not be occupied by the clinical staff because the risk is too great. Whogets blamed for that?
Its In the Water
Pseudomonas aeruginosa accounts for10 percent to 20 percent of nosocomial infections, and about 1,400 deaths peryear, says Matthew Freije, president of HC Information Resources, a firm thatoffers publications, consulting, and seminars pertaining to legionella andother waterborne pathogens. Those 1,400 deaths per year are just fromnosocomial pneumonia caused by Pseudomonas aeruginosa, the organismcauses other illness also.
Legionella and pseudomonas posethe most consistent threat in the healthcare setting, says Freije, withhonorable mention to the mycobacterium species. Legionella has beenstudied far more than other waterborne pathogens, so we have more data on whichto base specific preventative measures, he says. Also, measures thatcontrol legionella will control a lot of the others as well.
Plumbing systems provide a hospitable habitat for waterbornepathogens, and cooling towers are a potential source for contamination,especially for legionella. It is thought that the domestic watersystems account for more nosocomial infections than cooling towers, saysFreije, but both need to be maintained to minimize risk. Patients who areimmunocompromised because of underlying illness or certain medications ortreatment are at highest risk, he adds.
The first step in prevention is making the decision toproactively try and control the bugs. Thats not as obvious as it mightsound, because many hospitals probably most are still in a reactivemode, says Freije. The CDCs new guidelines recommend maintaining watersystems to minimize legionella, which is a significant addition to its previousdocuments.
According to the CDC, about 90 percent of Legionnairesdisease cases go undetected, he continues. To improve patient care itsnecessary to minimize legionella in the water systems. There are numerouspreventive measures for domestic water systems and cooling towers pertaining todesign, installation, operation and maintenance. The good thing is that most ofthe preventive measures are not costly, and provide additional benefits such asincreased efficiency or longer equipment life.
Legionnaires prevention is a pretty good bargain, actually,because risk can be significantly reduced fairly inexpensively. Its not likeasbestos, where you might spend millions of dollars to achieve a relativelysmall increment of risk reduction.
Moreover, taking these preventive measures for legionella notonly improves patient care, but is also the best way to avoid a lawsuit, or todefend a lawsuit of a case if disease occurs despite the preventive efforts. Many attorneys do not realize this, continues Freije.The old way of thinking was that a head-in-the-sand approach to Legionnairesdisease was the best legal defense, but attorneys who have been involved inLegionnaires litigation know better.
Beyond cooling towers and plumbing systems, specific itemssuch as decorative fountains, respiratory care equipment, hydrotherapy tanks andpools, ice machines and storage chests can serve as sources of pathogens. Anyequipment thats attached to the water system needs to be considered, saysFreije. Its best to minimize equipment attached to the water system.
James cites an instance when he found waterborne Aspergillusfumigatus in the p-trap of a hospital sink. The trap had been recently snaked by a plumber, he recalls. I didntknow this work had been done, and came right behind the plumber and did somemicrobiological sampling for fungi. All of a sudden I grew more Aspergillusfumigatus than Id ever seen in 12 years of sampling. I couldnt figureout why I was getting so much at this one site, but in no other. I did some factchecking and found out this event had occurred; I went down into that trap andwas able to find Aspergillus fumigatus. In a unit full ofimmunocompromised patients, this is not good to have. We made sure these trapswere cleaned and that we flushed them more frequently.
In yet another example of the waterborne pathogen shell game,James recounts the case of a technician who would start exhibiting respiratorydistress an hour after starting work every morning. Upon investigation, Jamesdiscovered an energy management policy wherein the air conditioning system wasshut down every night at 10 p.m., meaning no air supply, neither heat norcooling, reached the lab each night but the exhaust was kept on. Thatmade the lab strongly negative, he says. The culprit proved to be a flooding floordrain, which was becoming positive and blowing pathogens into the lab. When she came in every morning, she was inhaling everythingthat was coming out of the floor drain all night long. We found out through someimmunologic testing that she was allergic to only one fungus: Aspergillus fumigatus. We sent aserum sample off to Johns Hopkins, and found out she had precipitating antibodyto Aspergillus fumigatus, which is an indication of hypersensitivitypneumonitis.
We closed the circle, sealed the floor drain, andsymptomotalogy went away. You never know what is lurking in these remote places.
On April 29, 2004, representatives from the Association for Professionals inInfection Control and Epidemiology (APIC) and the American Hospital Association(AHA) met with Occupational Safety and Health Administration (OSHA)administrator John Henshaw and other OSHA officials, regarding the agencysrecent decision to include exposure to patients with potentially infectious TBunder the General Industry Respiratory Protection Standard.
The push/pull debate between OSHAs stance on fit testingand hospitals view of the impending edict as time consuming, expensive andunfeasible rages on.
I would like to have some science-based evidence thatclearly indicates that respirators do indeed make a difference in interruptingdisease transmission, says Terri Rearick, RN, BS, CIC, administrator, safetyservices at Childrens Memorial Hospital in Chicago. We still haventseen the science behind the need for and use of respirators for biologic agents.We may learn more if SARS presents itself again and challenges us to betterunderstand the relationship. The cost of respirator fit testing and routine refittesting to healthcare is potentially staggering. Our healthcare dollars are so precious; we want to make surethat if we are using personal protective equipment that actually interruptsdisease transmission and that we are using them in the best manner possible.
Nothing has really been finalized, so as healthcareworkers, were all waiting for the other shoe to drop, and to find out exactlywhat it is that we will be required to do. I think OSHA struggles so much withtaking that industrial model and trying to apply it to medicine. Its just not always a fit.
Many infection control practitioners are scratching theirheads over the issue, waiting for a logical resolution. Henshaw stresses thatOSHAs primary concern is the protection of healthcare workers, and that theagency has no intention of imposing anything that is unnecessary or a waste ofresources.
A quick survey of APIC board members revealed what manyclinicians have been saying all along: protection of healthcare workers isparamount, but is annual fit testing necessary?
We want to be sure that personnel are very much aware thatthey need to wear the masks, and that they wear the proper size, that the propersize is available to them, that they know how to put them on and fit-check them.We have to be really careful that we make sure that our personnel know that. Wedont want to seem that were holding back on the OSHA regulations, we justdont believe in that part of the regulation. We believe that they should beworn, but we dont think its necessary to fit test them for TB.
-- Kathleen Meehan Arias, MS, MT, SM, CIC, Arias InfectionControl Consulting, Crownsville, Md.
I think fit testing is important when you hire a newemployee, and I think its important that you do a physical, sit-downconversation with the employee each year after theyve been fit-tested to make sure what you have on your records is correct:that they have not lost too much weight, had facial surgery. You need to discuss everything with them. I think its also good for them to review the procedure forputting on the mask correctly, and making a fit check. Its important for themto review that every year if theyre not an employee that goes into isolationrooms periodically.
-- Christine J. Nutty, RN, MSN, CIC, infection controlpractitioner, Western Baptist Hospital, Paducah, Ky.
The small hospital that I worked at in southern New Mexicoactually did fit test its employees every year. They had a good system for itand it worked, but I used to say, what the heck are we doing here? Why are we bothering? What are we really accomplishing? Whatsthe return here? Im not sure there is one.
-- Gail Harris, RN, MS, MA, CIC, senior risk consultant, GEMedical Protective, Las Vegas, Nev.