Draft Isolation Guideline Addresses New Challenges, ClarifiesOld Issues

By Kelly M. Pyrek

Clinicians likely will have to wait until late 2004 or early 2005 for the issuance of the fi nal “Guidelines for Isolation Precautions: Preventing Transmission of Infectious Agents in Healthcare Settings 2004” from the Centers for Disease Control and Prevention (CDC). Earlier this summer, the CDC’s Healthcare Infection Control Practices Advisory Committee (HICPAC) issued a draft guideline that updates and expands the “1996 Guideline for Isolation Precautions in Hospitals.” The draft was published in the June 14, 2004 Federal Register.

The period for public comment closed in mid-August, and in early June, one of the draft’s authors, Marguerite M. Jackson, RN, PhD, CIC, FAAN, of the UCSD School of Medicine, told attendees of the annual meeting of the Association for Professionals in Infection Control and Epidemiology (APIC) that a final guideline could be issued as early as fall 2004 or as late as spring 2005. Original directives in 1970 and 1975 were revised in 1983 and in 1996, and work on the most current guidelines was started in 2000, Jackson said.

APIC is urging clinicians to remember that the draft document was intended for public comment only, and that facilities “should not modify their practices or policies based on these preliminary recommendations,” according to the organization. APIC is in the process of finalizing its comments to the CDC regarding these guidelines, according to Jennifer Thomas, APIC’s director of governmental affairs.

The five-part draft guideline addresses several important developments since 1996:

• The transition from acute-care to other healthcare settings such as ambulatory care
• The emergence of new pathogens such as severe acute respiratory syndrome (SARS) and the increased threat of bio-terrorism
• Evidence that environmental controls decrease the risk of life-threatening fungal infections in the most severely immuno-compromised individuals
• Evidence that factors such as nurse staffing levels and levels of adherence by healthcare workers (HCWs) to infection control practices, has led to new emphasis on administration’s support of infection control programs
• Continued increase in the incidence of healthcare-acquired infections (HAIs) caused by multi-drug-resistant organisms (MDROs)

The draft guideline reaffirms Standard Precautions as the foundation for preventing transmission of infectious agents during healthcare personnel/patient interactions, and recognizes the new Respiratory Hygiene/Cough Etiquette, which grew from the SARS epidemic. This protocol has been incorporated into the CDC’s planning documents for SARS and pandemic influenza.

Most notably, the guideline includes three changes in terminology:

1. “Transmission-based Precautions” has been replaced with “Expanded Precautions” to reflect the need for additional measures to prevent transmission when the route of transmission is not interrupted completely by Standard Precautions, or when a protective environment is needed to prevent acquisition of fungi from the environment.

2. “Airborne Precautions” has been replaced with “Airborne Infection Isolation” to be consistent with the revised “Guidelines for Preventing the Transmission of Mycobacterium tuberculosis in Healthcare Settings 2004,” the “Guidelines for Environmental Infection Control in Healthcare Facilities,” and the American Institute of Architects guidelines for design and construction of hospitals.

3. The term “nosocomial infection” has been replaced with “healthcare-associated infection” (HAI) to refer to infections associated with healthcare delivery in any setting.

In Part I, the guideline reviews elements of the chain of infection and the interrelationship of these elements in the epidemiology of HAIs, as well as discusses the modes of transmission. Under discussion and debate in the infection control community is the definition of droplet transmission as well as droplet size, in light of experimental studies with smallpox and investigations of the global SARS outbreak of 2003. Clinicians are encouraged to consider the definitions as presented in the guideline as examples and not criterion for deciding when a mask should be donned to protect against exposure.

A new classification of aerosol transmission was proposed when evaluating routes of SARS transmission: 1. obligate: under natural conditions, disease occurs following transmission of the agent only through small particle aerosols; 2. preferential: natural infection results from transmission through multiple routes, but small particle aerosols are the predominant route; and 3. opportunistic: agents that naturally cause disease through other routes but under certain environmental conditions may be transmitted via fine particle aerosol.

Part I reviews and discusses the six groups or types of organisms with epidemiologically important infection control implications: multi-drug-resistant organisms (MDROs), agents of bio-terrorism, prions, SARS-CoV, monkeypox, and avian influenza A (H5N1) viruses, as well as discusses transmission risks associated with specific types of healthcare settings, including hospitals, intensive care units, burn units, pediatrics, non-acute healthcare settings, long-term care, ambulatory care, and home care.

Lastly, Part I discusses healthcare system components that infl uence the effectiveness of precautions to prevent transmission, including safety culture and organizational characteristics, nurse staffing ratios, adherence of healthcare personnel to recommended guidelines, and clinical microbiology laboratory support.

Part II reviews various infection-prevention measures, including administrative support of infection control practices; education of healthcare workers, patients and their families; hand-hygiene protocol; use of personal protective equipment (PPE) and the new fit-testing requirements for respirators; safe work practices to prevent HCW exposure to bloodborne pathogens; environmental measures as a part of Standard Precautions; as well as adjunctive measures such as antimicrobial management programs, post-exposure chemoprophylaxis with antiviral or antibacterial agents, and vaccines used both for pre- and post-exposure prevention.

Part III reviews and discusses the two tiers of transmission precautions:

• Standard Precautions is intended to be applied to the care of all patients in all healthcare settings, regardless of the suspected or confirmed presence of an infectious agent. The guideline emphasizes, “Implementation of Standard Precautions constitutes the primary strategy for successful prevention of healthcare-associated transmission of infectious agents among patients and healthcare personnel.”
• Expanded Precautions are for patients who are known or suspected to be infected with epidemiologically important pathogens that require additional control measures to prevent transmission.

The four categories of Expanded Precautions are: Contact Precautions, Droplet Precautions, Airborne Infection Isolation and Protective Environment. The guideline says that more than one category may be used for diseases that have multiple routes of transmission; when used either singularly or in combination, they are always to be used in addition to Standard Precautions.

Part III also discusses the new respiratory hygiene/cough etiquette that has been incorporated into infection control practices as one component of Standard Precautions (see www.cdc.gov/flu/professionals/infectioncontrol/resphygiene.htm).

The guideline provides for the following:

• Administrative responsibilities
• Education and training
• Surveillance
• Standard Precautions
• Expanded Precautions
• Prevention of transmission of MDROS
• Performance indicators

Discussion is taking place over the potential confl icts found between HICPAC’s “Guideline to Prevent Transmission of Infectious Agents in Healthcare Settings” and SHEA’s “Guideline for Preventing Nosocomial Transmission of Multi-drug Resistant Strains of Staphylococcus aureus and Enterococcus.” Even though infection control programs were created more than 30 years ago to help control antibiotic-resistant HAIs, experts say there has been little evidence of control in most facilities. So in 2000, the board of directors of SHEA made reducing antibiotic-resistant infections a strategic goal. After several more years without improvement in the rate of resistant-pathogen related infections, a SHEA task force was appointed to draft these evidence-based guidelines to prevent nosocomial transmission of such pathogens.

The guidelines focused on the two considered to be most out of control: methicillin-resistant Staphylococcus aureus (MRSA) and vancomycinresistant Enterococcus (VRE). Medline searches were conducted, spanning literature published from 1966 to 2002. The authors, Carlene Muto, MD; John Jernigan, MD; Belinda Ostrowsky, MD, MPH; Herve Richet, MD; William Jarvis, MD; John Boyce. MD; and Barry Farr, MD, MSc, concluded that active surveillance cultures are essential to identify the reservoir for spread of MRSA and VRE infections and make control possible using the CDC’s long-recommended contact precautions (see Infect Control Hosp Epidemiol 2003:24:362-386).

Attendees of the annual meeting of the Association for Professionals in Infection Control and Epidemiology (APIC) in June were treated to a lively discussion of the HICPAC and SHEA guidelines by William Jarvis, MD and William Scheckler, MD, in the first-ever “Science to Practice” session, sponsored by 3M Health Care.

In the debate, Jarvis said that the data clearly shows that the status quo isn’t working, and that routine surveillance can detect colonized patients. He added this is a natural equation, since colonization precedes infection. Jarvis emphasized that in healthcare facilities, the reservoir -- the colonized patient — is being ignored unless an outbreak or other problem is identifi ed. Jarvis argued that unless hospitals go on what he described as a “search and destroy” campaign and employ facility-wide, active surveillance, the problem of multi-drug resistant pathogens will persist.

Jarvis encouraged the members of the infection control community to demand that the CDC and HICPAC take a much more aggressive approach to combat VRE and MRSA using active surveillance and contact precautions. He urged APIC attendees to write to the CDC to express their concern that this was a “political issue, not a scientifi c issue.”

In the SHEA guidelines, the authors write, “Success in controlling MRSA has been greatest in countries that adhere to rigorous transmission-based control policies that include active surveillance cultures to identify colonized patients and strict application of barrier precautions for patients colonized or infected with MRSA.”

The SHEA recommendations are as follows:

• Active surveillance cultures to identify the reservoir for spread
• Use of proper hand hygiene
• Use of barrier precautions for patients known for suspected to be colonized or infected with MRSA or VRE
• Use of good antibiotic stewardship
• Decolonization or suppression of colonized patients
• Use of educational programs to raise awareness

In the debate with Jarvis, Scheckler said that “to those with a hammer, everything looks like a nail,” emphasizing that the SHEA guidelines could impose a costly, rigid protocol on hospitals. Scheckler said the HICPAC guidelines, as opposed to the SHEA guidelines, accentuated healthcare facilities’ needs for flexibility, adjusting protocol and clinical practice to the many different circumstances. He emphasized the need for hospitals to choose the highest-risk patients for culturing only, and not a blind allegiance to active surveillance. “If we’re not good at standard precautions, how good are we at contact precautions?” he asked the audience.

3M Health Care provided about 300 members of the audience with a wireless transmitter device capable of registering individuals’ “votes” after the debate between Jarvis and Scheckler. When asked if they agreed with the concepts put forth by the SHEA guidelines, 26 percent of those with transmitters agreed; 28 percent disagreed, and 46 percent were undecided. When asked if they agreed with the concepts put forth by the HICPAC guidelines, 28 percent of those with transmitters agreed, 17 percent disagreed, and 55 percent were undecided. When asked if they thought either guidelines were valid, 51 percent of those with transmitters agreed, 22 percent disagreed, and 27 percent had no opinion.