Infection Control Today - 11/2003: Clinical Update

Isolation Protocol Takes On New Meaning in SARS Era

By Kathy Dix

It used to be called paranoia. But now being a stickler for isolation guidelines is just good sense.

If SARS (severe acute respiratory syndrome), Norwalk-like virus and smallpox represent the Big Bad Wolf, consider isolation protocol to be the Woodcutter. The fall of 2002 brought several diseases to the forefront of American consciousness, and in response, the Centers for Disease Control and Prevention (CDC) released additional guidelines on proper isolation practices specific to these diseases. Terri Rearick, RN, BS, CIC, head of infection control at Illinois Childrens Memorial Hospital, the educational facility for Northwestern Universitys Feinberg School of Medicine, says that her own facility has responded with adaptations in construction. We have adapted to isolation changes by adding two new negative air pressure rooms to our emergency department in light of SARS and the smallpox/bioterrorism preparedness efforts, she says.

Not only that, but the hospital has updated its isolation categories; they now rank patients according to six different classifications: the standard Airborne, Droplet and Contact Isolation, but also two combined categories of Airborne/Contact and Droplet/Contact. We also use protective isolation for our stem cell and bone marrow transplant patients, she clarifies.

Fear has not been a motivating factor in changing basic hospital policy; instead, Rearick says, We try not to be reactionary and be proactive whenever possible.

Like other hospitals, Childrens Memorial has instituted its own SARS policy, and has increased fit testing for personal respirator use.

Childrens Memorial has also purchased three positive air pressure respirators and is working with the city of Chicago in our bioterrorism planning, notes Rearick. This planning also covers biological challenges that are naturally occurring/emerging infectious diseases.

In general, there have been no paradigm shifts in infection control due to illnesses such as SARS or smallpox, says Peter R. Wolfe, MD, vice chief of medical staff at Century City Hospital in West Los Angeles, a specialist in internal medicine and infectious diseases, and an associate clinical professor of medicine at the University of California at Los Angeles.

Certainly the bioterrorism issue has been important in infection control the past two years; I would say that the greatest effect has been on emergency rooms, which will be the first line of defense against potential terrorist attacks. Much of this is educating the front line personnel about what the agents are and how to recognize them, adds Wolfe.

It is true that the increasing prevalence of VRE (vancomycin-resistant enterococcus and multidrug-resistant gram negative enterics in the hospital setting has led CDC and JCAHO (Joint Commission on Accreditation of Healthcare Organizations) to focus more attention on limiting the spread of these and other nosocomial pathogens, he explains. However, its interesting that some hospitals in the local area have stopped isolating MRSA patients.

The real changes to infection control procedures have been obvious ones such as the new guidelines from the CDC emphasizing the magnitude of handwashing, says Wolfe. The addition of alcohol-based hand rubs as an alternative to soapand- water handwashing has been the biggest modification, followed by other recommendations to continue using gloves and to utilize traditional handwashing when hands are visibly soiled.

CDC guidelines also recommend that healthcare workers in contact with high-risk patients avoid artificial nails, and wear only short natural nails, and that healthcare facilities monitor improvements in adherence to hand hygiene guidelines.

The CDCs HICPAC committee has appointed a small group to update its existing isolation guidelines, says Rita McCormick, RN, CIC, senior infection control practitioner for the University of Wisconsin Hospitals and Clinics, but the new guidelines will not be published until 2004 or 2005. However, the CDC has addressed Norwalk virus, SARS and smallpox in separate publications; of note, any of the existing viral gastroenteritis diseases (including Norwalk-like viruses) can readily be handled using existing guidelines addressing acute diarrhea of unknown etiology until the infectious etiology is determined, says McCormick, and then the specific precautions can be utilized if different. Typically, contact precautions are used for various types of diarrhea in young children or incontinent adults.

Norwalk Virus or Norwalk-like Virus

In 2002, thousands of travelers were felled by the Norwalk virus or one of its close norovirus relatives. Cruise ships especially were prime havens for the virus that causes acute gastroenteritis lasting one to two days. Transmitted through fecal-oral contact, Norwalk virus appears to be easily transmitted from person to person, especially in the close quarters associated with a ship or a nursing home.

First linked with gastroenteritis in 1972, Norwalk virus was associated with an epidemic of gastroenteritis that occurred in 1968 in Norwalk, Ohio. Over just two days, 50 percent of an elementary schools population developed acute gastroenteritis.1

Norwalk virus is cunning it can be found in contaminated food or water, or be transmitted by touching an infected persons hand, even a stair railing, doorknob or salad tongs at the buffet. And, strangely enough, it appears that susceptibility to infection may be genetically determined, with people of O blood group being at greatest risk for severe infection, says the CDC.2

The best means of preventing the spread of infection is to follow hand hygiene guidelines and dispose of infectious materials; in an inpatient setting, contact isolation precautions should be taken. Notify the state board of health for all epidemic outbreaks of Norwalk virus (two or more people who shared a common meal) so it can investigate potential outbreak centers and prevent further transmission, recommend two physicians in an e-article about Norwalk virus.1


SARS, a recently discovered coronavirus that appears to have jumped from animals to humans in the late summer or early fall of 2002, has been surprising in its sporadic ability to spread rapidly. So-called superspreaders who either expose many others to the disease before they are diagnosed and treated, or who happen to have a particularly vigorous strain of the disease have been capable of spreading the disease to hundreds, while others not wearing masks or washing their hands infect few.

In response to the SARS outbreak of late 2002 and early 2003, the CDC released specific guidance on appropriately dealing with SARS patients. First, when a suspect SARS patient is admitted, infection control personnel should be notified immediately; second, standard precautions are necessary, in addition to eye protection for all patient contact.3

Not only that, but contact and airborne precautions should be observed, and all healthcare workers in contact with the patient should have a qualitative fit test for their N-95 respirators. If N-95 respirators are not available, personnel should wear surgical masks.

Persons seeking medical care for an acute respiratory infection should be asked about possible exposure to someone with SARS or recent travel to an area with SARS, say the guidelines. If SARS is suspected, the patient should be provided with a surgical mask, or asked to cover the mouth with a disposable tissue while coughing, talking or sneezing. This patient should be kept separate from others in the reception area, and the CDC recommends removing him or her to a private room with negative pressure. Healthcare workers in contact with such patients should wear N-95 respirators, follow standard and contact precautions and wear eye protection.

In the home setting, such patients should wear surgical masks, or, if this is impossible, housemates should wear surgical masks when in close contact, and should utilize careful hand hygiene with soap and water, or alcohol-based hand rubs if the hands are not visibly soiled.

Suspected Smallpox

In its Guidelines for Environmental Infection Control in Health Care Facilities, the CDC recommends that patients with smallpox be placed in negative-pressure rooms at illness onset; specific suggestions in the subsection on ventilation requirements indicate that air pressure should be monitored daily, with audible manometers or smoke tubes at the door, or permanent visual monitoring mechanisms.4

Such rooms should be well-sealed, have proper air intake and exhaust ports, and should have self-closing devices on all exit doors. Air should be exhausted outside, away from air-intake and populated areas, or recirculated after being passed through a HEPA filter.

In addition, healthcare workers exposed to the patient should be properly shielded with personal respiratory protection.

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