Draft Isolation Guideline Addresses New Challenges, ClarifiesOld Issues

October 1, 2004

Draft Isolation Guideline Addresses New Challenges, ClarifiesOld Issues

By Kelly M. Pyrek

Clinicianslikely will have to wait until late 2004 or early 2005 for the issuance of thefi nal Guidelines for Isolation Precautions: Preventing Transmission ofInfectious Agents in Healthcare Settings 2004 from the Centers for DiseaseControl and Prevention (CDC). Earlier this summer, the CDCs HealthcareInfection Control Practices Advisory Committee (HICPAC) issued a draft guidelinethat updates and expands the 1996 Guideline for Isolation Precautions inHospitals. The draft was published in the June 14, 2004 Federal Register.

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

APIC is urging clinicians to remember that the draft documentwas intended for public comment only, and that facilities should not modifytheir practices or policies based on these preliminary recommendations,according to the organization. APIC is in the process of finalizing itscomments to the CDC regarding these guidelines, according to Jennifer Thomas,APICs director of governmental affairs.

The five-part draft guideline addresses several importantdevelopments since 1996:

  • The transition from acute-careto other healthcare settings such as ambulatory care

  • The emergence of new pathogens such as severe acuterespiratory syndrome (SARS) and the increased threat of bio-terrorism

  • Evidence that environmental controls decrease the riskof life-threatening fungal infections in the most severely immuno-compromisedindividuals

  • Evidence thatfactors such as nurse staffing levels and levels of adherence by healthcareworkers (HCWs) to infection control practices, has led to new emphasis onadministrations support of infection control programs

  • Continued increase in the incidence ofhealthcare-acquired infections (HAIs) caused by multi-drug-resistant organisms(MDROs)

Part 1: Review of Scientific Data Regarding Transmission ofInfectious Agents in Healthcare Settings

The draft guideline reaffirms Standard Precautions as thefoundation for preventing transmission of infectious agents during healthcarepersonnel/patient interactions, and recognizes the new Respiratory Hygiene/CoughEtiquette, which grew from the SARS epidemic. This protocol has beenincorporated into the CDCs planning documents for SARS and pandemic influenza.

Most notably, the guideline includes three changes interminology:

1. Transmission-based Precautions has been replaced withExpanded Precautions to reflect the need for additional measures toprevent transmission when the route of transmission is not interruptedcompletely by Standard Precautions, or when a protective environment is neededto prevent acquisition of fungi from the environment.

2. Airborne Precautions has been replaced with AirborneInfection Isolation to be consistent with the revised Guidelines forPreventing the Transmission of Mycobacterium tuberculosis in Healthcare Settings2004, the Guidelines for Environmental Infection Control in HealthcareFacilities, and the American Institute of Architects guidelines for designand construction of hospitals.

3. The term nosocomial infection has been replaced withhealthcare-associated infection (HAI) to refer to infections associated with healthcaredelivery in any setting.

In Part I, the guideline reviews elements of the chain ofinfection and the interrelationship of these elements in the epidemiology ofHAIs, as well as discusses the modes of transmission. Under discussion and debate in the infection control communityis the definition of droplet transmission as well as droplet size, in light ofexperimental studies with smallpox and investigations of the global SARSoutbreak of 2003. Clinicians are encouraged to consider the definitions aspresented in the guideline as examples and not criterion for deciding when amask should be donned to protect against exposure.

A new classification of aerosol transmission was proposedwhen evaluating routes of SARS transmission: 1. obligate: under naturalconditions, disease occurs following transmission of the agent only throughsmall particle aerosols; 2. preferential: natural infection results fromtransmission through multiple routes, but small particle aerosols are thepredominant route; and 3. opportunistic: agents that naturally causedisease through other routes but under certain environmental conditions may betransmitted via fine particle aerosol.

Part I reviews and discusses the six groups or types oforganisms 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 asdiscusses transmission risks associated with specific types of healthcaresettings, 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 thatinfl uence the effectiveness of precautions to prevent transmission, includingsafety culture and organizational characteristics, nurse staffing ratios,adherence of healthcare personnel to recommended guidelines, and clinicalmicrobiology laboratory support.

Part II: Fundamental Elements to Prevent Transmission ofInfectious Agents in Healthcare Settings

Part II reviews various infection-prevention measures,including administrative support of infection control practices; education ofhealthcare workers, patients and their families; hand-hygiene protocol; use ofpersonal protective equipment (PPE) and the new fit-testing requirements forrespirators; safe work practices to prevent HCW exposure to bloodbornepathogens; environmental measures as a part of Standard Precautions; as well asadjunctive measures such as antimicrobial management programs, post-exposurechemoprophylaxis with antiviral or antibacterial agents, and vaccines used bothfor pre- and post-exposure prevention.

Part III: HICPAC/CDC Precautions to Prevent Transmission ofInfectious Agents

Part III reviews and discusses the two tiers of transmissionprecautions:

  • 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 guidelineemphasizes, Implementation of Standard Precautions constitutes the primarystrategy for successful prevention of healthcare-associated transmission ofinfectious agents among patients and healthcare personnel.

  • Expanded Precautions are forpatients who are known or suspected to be infected with epidemiologicallyimportant pathogens that require additional control measures to preventtransmission.

The four categories of Expanded Precautions are: ContactPrecautions, Droplet Precautions, Airborne Infection Isolation and ProtectiveEnvironment. The guideline says that more than one category may be used fordiseases that have multiple routes of transmission; when used either singularlyor in combination, they are always to be used in addition to StandardPrecautions.

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

Part IV: Recommendations

The guideline provides for the following:

  • Administrative responsibilities

  • Education and training

  • Surveillance

  • Standard Precautions

  • Expanded Precautions

  • Preventionof transmission of MDROS

  • Performanceindicators

Discussion is taking place over the potential confl icts foundbetween HICPACs Guideline to Prevent Transmission of Infectious Agents inHealthcare Settings and SHEAs Guideline for Preventing NosocomialTransmission of Multi-drug Resistant Strains of Staphylococcus aureus andEnterococcus. Even though infection control programs were created more than30 years ago to help control antibiotic-resistant HAIs, experts say there hasbeen little evidence of control in most facilities. So in 2000, the board ofdirectors of SHEA made reducing antibiotic-resistant infections a strategicgoal. After several more years without improvement in the rate ofresistant-pathogen related infections, a SHEA task force was appointed to draftthese evidence-based guidelines to prevent nosocomial transmission of suchpathogens.

The guidelines focused on the two considered to be most out ofcontrol: methicillin-resistant Staphylococcus aureus (MRSA) andvancomycinresistant 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 thereservoir for spread of MRSA and VRE infections and make control possible usingthe CDCs long-recommended contact precautions (see Infect Control HospEpidemiol 2003:24:362-386).

Attendees of the annual meeting of the Association forProfessionals in Infection Control and Epidemiology (APIC) in June were treatedto a lively discussion of the HICPAC and SHEA guidelines by William Jarvis, MDand 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 thatthe status quo isnt working, and that routine surveillance can detectcolonized patients. He added this is a natural equation, since colonizationprecedes infection. Jarvis emphasized that in healthcare facilities, thereservoir -- the colonized patient is being ignored unless an outbreak orother problem is identifi ed. Jarvis argued that unless hospitals go on what hedescribed 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 controlcommunity to demand that the CDC and HICPAC take a much more aggressive approachto combat VRE and MRSA using active surveillance and contact precautions. Heurged APIC attendees to write to the CDC to express their concern that this wasa political issue, not a scientifi c issue.

In the SHEA guidelines, the authors write, Success incontrolling MRSA has been greatest in countries that adhere to rigoroustransmission-based control policies that include active surveillance cultures toidentify colonized patients and strict application of barrier precautions forpatients colonized or infected with MRSA.

The SHEA recommendations are as follows:

  • Active surveillance cultures toidentify the reservoir for spread

  • Useof proper hand hygiene

  • Useof barrier precautions for patients known for suspected to be colonized orinfected with MRSA or VRE

  • Useof good antibiotic stewardship

  • Decolonizationor suppression of colonized patients

  • Useof educational programs to raise awareness

In the debate with Jarvis, Schecklersaid that to those with a hammer, everything looks like a nail,emphasizing that the SHEA guidelines could impose a costly, rigid protocol onhospitals. Scheckler said the HICPAC guidelines, as opposed to the SHEAguidelines, accentuated healthcare facilities needs for flexibility,adjusting protocol and clinical practice to the many different circumstances. Heemphasized the need for hospitals to choose the highest-risk patients forculturing only, and not a blind allegiance to active surveillance. If werenot good at standard precautions, how good are we at contact precautions? heasked the audience.

3M Health Care provided about 300 members of the audience witha wireless transmitter device capable of registering individuals votes after the debate between Jarvis and Scheckler. When asked ifthey agreed with the concepts put forth by the SHEA guidelines, 26 percent ofthose with transmitters agreed; 28 percent disagreed, and 46 percent wereundecided. When asked if they agreed with the concepts put forth by the HICPACguidelines, 28 percent of those with transmitters agreed, 17 percent disagreed,and 55 percent were undecided. When asked if they thought either guidelines werevalid, 51 percent of those with transmitters agreed, 22 percent disagreed, and27 percent had no opinion.