August 13, 2004 - Guideline for Isolation Precautions: Preventing Transmission of Infectious Agents in Healthcare Settings 2004

Resource Center, Attention: ISO Guide
Division of Healthcare Quality Promotion
Centers for Disease Control and Prevention
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To Whom It May Concern:

The American Society for Microbiology (ASM) is pleased to provide comments to the Centers for Disease Control and Prevention (CDC) on the draft “Guideline for Isolation Precautions: Preventing Transmission of Infectious Agents in Healthcare Settings 2004,” published in the June 14, 2004 Federal Register. The ASM is the largest scientific society dedicated to the advancement of the microbiological sciences and their application for the common good. The Society represents more than 40,000 individual members who work as researchers, educators, clinicians, administrators and technical personnel in academic, industry, government, clinical and public health laboratories and institutions. The following comments were developed by ASM’s Public and Scientific Affairs Board’s Committee on Laboratory Practices and Committee on Professional Affairs.

General Comments


The ASM commends the CDC for its work on this important document which addresses infection control in many healthcare settings including those beyond the traditional hospital setting. We also appreciate the creation of and attention to new categories of precautions, such as “Respiratory Hygiene/Cough Etiquette” and “Protective Environment.” However, since this document is focused more towards healthcare workers with patient contact, we recommend that a separate document be created specific to laboratories, that advises on the prevention of transmission of infectious diseases to laboratory workers. A document of this kind would be of great value, especially if it focuses on newer agents including SARS and addresses recent incidents such as the acquisition of N. meningitidis infections in the laboratory.

Specific Comments

I.C.1. Multidrug-Resistant Organisms:
On p. 16, Multidrug-Resistant Organisms (MDROs) are defined as “microorganisms (predominantly bacteria) that are resistant to one or more classes of antimicrobial agents.” We recommend that CDC provide a more detailed definition which includes the fact that MDROs are one or more agents for which natural or intrinsic resistance does not exist. Furthermore, while the document seeks to “replace pathogen-specific recommendations” as outlined on page 9, objective 4, we suggest that there be a continued emphasis on pathogen-specific recommendations (e.g. for VRE, MRSA, VISA/VRSA, ESBL, etc), plus additional guidelines for dealing with an apparent problem involving any other novel or unusual MDRO, or any other organism for which an association with a healthcare-associated infection (HAI) is likely.

It would be useful if a table (appendix) listing organisms (MDRO and others) reported to be strongly associated with HAI was included in the guideline. Infection control practitioners (ICPs) may wish to focus attention on the discovery of an isolate in this category (e.g. Ralstonia pickettii, Ochrobactrum anthropi, and Enterobacter sakazakii). An additional table (appendix) listing the websites cited in the text describing agent-specific infection control guidelines, would also be helpful. CDC may want to make these guidance documents easily accessible through a single infection control website link rather than having ICPs go through the organism specific search sites. Regular updates to this table should also be provided.

We also recommend that the document provide information regarding when to screen for MDROs. Currently, the need to screen patients for extended spectrum beta-lactamases (ESBLs) is very controversial, yet this is one of the MDROs that is described in the document that may need surveillance and/or screening performed. In addition, the MRSA and VRE screening situations could be more clearly identified. Along this line, ASM recommends adding a comment on page 85 to discourage the transfer of patients between wards/hospitals, etc., simply to accommodate “bed utilization.” If the patient carries a MDRO and is transferred to sites where there are more “open beds,” the chance of spreading the organism is increased. It should be noted that this is different for C. difficile where asymptomatic carriage has not been identified as a need to limit transfer to long term care facilities etc.

I.C.6. Avian influenza A: The measures recommended for care of humans with suspected or confirmed H5N1 disease “include vaccination of healthcare personnel with the appropriate seasonal human influenza vaccine.” While this is an excellent practice for prevention of known human strains of influenza A, we note that this is ineffective against avian viruses which carry hemagglutinin and neuraminidase glycoproteins not present in available vaccines.

I.G.III. Adherence of healthcare personnel to recommended guidelines (pp. 35-36) and II.G. Education and Training (p. 65): A paragraph related to complex medical devices (e.g. flexible endoscopes) should be included in both of these sections. The majority of problems associated with improper reprocessing that leads to infection transmission have been associated with improperly trained staff being involved in reprocessing. This includes staff who were not properly trained when they were initially employed, and also includes staff who “cover” or “fill in” (e.g. after hours and for holidays). This should be identified as a problem that needs to be addressed and that such “fill in” of improperly trained personnel is unacceptable. More specifically, on p. 35, we recommend adding a bullet that addresses turn-around-time, i.e., “Ensure that the turn-around-time (TAT) for infection control support services is optimal, e.g. surveillance cultures, and especially the use of molecular testing.” In addition, we recommend that a companion document be created and referenced in this guideline that delineates the microbiologic methods recommended for surveillance cultures or other test modalities mentioned on p.36. It should be noted that on-going active laboratory surveillance cultures might require additional microbiology laboratory staffing which should be supported by the healthcare organization’s administration. Finally, the description of clinical microbiology laboratory support on p. 36, should delineate acceptable methods for conveyance of data (telephone, fax, web-based, HIS/LIS), and if possible, the most desirable method should be stated. Any relevant JCAHO requirements should also be included.

II.C. Hand Hygiene: The document largely ignores adequate hand-hygiene for control of nosocomial C. difficile. Section II.C. states that alcohol-based products for hand disinfection are preferred over antimicrobial or plain soap and water because of its superior microbiocidal activity. However, the CDC’s Guideline for Hand Hygiene in Health-Care Settings, p. 17 (MMWR 51: RR-16, 2002) states that none of the agents used in antiseptic handwash or hand-rub preparations are reliably sporicidal against Clostridium spp. or Bacillus spp. It further states that “HCWs should be encouraged to wear gloves when caring for patients with C. difficile associated diarrhea.” We recommend addressing this area of concern in the Hand Hygiene section.

III.A.1 New Standard Precautions for patients: Respiratory Hygiene/Cough Etiquette (pp. 55-56) and C. Respiratory Hygiene/Cough Etiquette (pp. 69-71): Patients with Respiratory Infections: While we agree with the recommendation to spatially separate patients with respiratory infections by more than three feet, we question the feasibility or likelihood of doing so in emergency waiting rooms or outpatient clinic waiting rooms; we suggest that the use of masks on such patients might reduce this need for spatial separation.

Thank you for the opportunity to comment. We would be pleased to respond to any questions or requests for additional information.

Ruth L. Berkelman, Ph.D., Chair, Public and Scientific Affairs Board
Joseph M. Campos, Ph.D., Chair, Committee on Laboratory Practices