Oct 22, 2003 (CIDRAP News) – A new document from the Centers for Disease Control and Prevention (CDC) lays out a long list of recommendations for providing the rigorous surveillance and containment that are seen as the keys to controlling SARS (severe acute respiratory syndrome), should the disease reappear.
The guidelines are intended for local public health and healthcare officials, who "provide the first line of readiness and action" for combating the disease, the 169-page report says. The document is described as a working draft that will be updated regularly.
"The basic strategy that controlled SARS outbreaks worldwide was rapid and decisive surveillance and containment," the report says. In the absence of effective vaccines or drugs, the strategy will be the same if SARS reappears in coming months. Containment will depend on rapid detection and isolation of cases, tracing and monitoring of patients' contacts, thorough infection control precautions, and, in some cases, quarantine of potentially infected people.
Titled "Public Health Guidance for Community-Level Preparedness and Response to Severe Acute Respiratory Syndrome (SARS)," the guidelines were released last week. They were written by the CDC's SARS Preparedness Committee, which convened eight working groups at meetings in August and September. The report has sections on command and control, surveillance, healthcare facilities, community containment measures, travel-related transmission risk, laboratory diagnosis, and communication.
The report lists some key lessons from this year's global outbreak. One was that laboratory tests, though sensitive and specific, do not reliably detect the SARS coronavirus early in the course of the disease. Another was that SARS transmission "is neither regional nor national but rather confined to limited geographic—and even institutional—settings," and response measures therefore must "reflect local characteristics and resources."
The longest single section of the report is the one on healthcare facilities. "All hospitals should be equipped and ready to care for a limited number of SARS patients as part of routine operations and also to care for a larger number of patients in the context of escalating transmission," the chapter states.
Topping the list of "lessons learned" for hospitals is that strict use of contact and droplet precautions (surgical masks, gowns, and gloves) and eye protection seems to prevent SARS transmission in most cases. However, airborne precautions—including respirator masks that filter out airborne particles—"may provide additional protection in some instances."
The recommended surveillance strategies for hospitals depend on whether or not SARS is present anywhere in the world. In the absence of SARS, hospitals should screen all pneumonia patients for possible risk factors, such as recent travel to an area previously affected by SARS, the guidelines say. Also, all outpatient facilities should post entrance signs asking new patients to report any respiratory symptoms and describing "respiratory hygiene" precautions.
In the presence of SARS anywhere in the world, healthcare facilities should determine when to begin actively screening people entering the facility for SARS risk factors and symptoms. In addition, all patients reporting to emergency rooms or hospital clinics with a fever or symptoms of lower respiratory tract infection should be screened for SARS risk factors.
Only "trained and fit-tested" emergency staff members should evaluate possible SARS patients, and they should wear "appropriate personal protective equipment" when doing so, the document says. But it doesn't specify that equipment or whether it should include face masks that filter out particulates, such as N-95 respirators. Additional information on this point was not immediately available from the CDC.
In the global absence of SARS, the document says, "Evaluation and management for possible SARS should be considered only for adults, unless there are special circumstances that make the clinician and health department consider a child to be of potentially higher risk."
Infection control steps in healthcare facilities should include an emphasis on "respiratory etiquette" to control the SARS virus and other respiratory pathogens, the CDC says. A "universal respiratory etiquette strategy" includes, among other things:
- Providing surgical masks or tissues to all patients presenting with respiratory symptoms
- Segregating patients with respiratory symptoms from other patients and putting them in a private room or cubicle as soon as possible
- Use of surgical masks by healthcare workers when evaluating patients with respiratory symptoms
- Providing hand hygiene materials in waiting areas and encouraging patients with respiratory symptoms to use them
- Considering the use of plexiglass barriers to protect registration and triage staff from unmasked patients
Because airborne transmission of SARS has not been ruled out, SARS patients who require hospital care should be placed in airborne infection isolation rooms (AIIRs) or special SARS units or wards, the CDC says. AIIRs—single rooms with negative air pressure—should be used when possible. But if AIIRs are scattered throughout the hospital or there are too many SARS patients, patients "may be cohorted in single rooms on nursing units that have been modified to accommodate SARS patients."
In case of a large outbreak, healthcare officials also should consider the possibility of designating a SARS hospital, though that approach has many drawbacks, the report says.
A section of the guidelines on community containment measures goes into detail on non-hospital isolation of patients and quarantine of potentially exposed people. Relevant lessons from this year's outbreaks, it says, include the following:
- Most, but not all, SARS patients have a history of exposure to another patient or to a setting with known SARS transmission.
- Quarantine was an integral part of SARS control in some places with extensive transmission.
- "Quarantine does not have to be mandatory, and compliance does not have to be 100% to be effective."
- SARS planning should include measures to reduce the financial, social, and psychological impact of quarantine.
- Clear communication about the purposes and duration of quarantine and how people under quarantine will be supported is necessary to generate public trust, without which quarantines won't succeed.
See also:
CDC page with link to the full guidelines document and individual sections
http://www.cdc.gov/sars/guidance/index.html
