SARS: Interim Guidelines for Severe Acute Respiratory Syndrome

CDC issued its first health alert regarding severe acute respiratory syndrome (SARS) on March 15, 2003. Since that time the Vermont Department of Health has been working to keep healthcare workers informed of the latest development and performing case-finding for possible cases in Vermont. Two Vermont residents have been identified as being suspected cases of SARS after arrival from endemic regions in Southeast Asia. Both had mild disease and did not need to be hospitalized.

The following are CDC recommendations as of April 7, 2003. These recommendations are subject to change as more information becomes available. We urge you to keep yourself informed with the latest developments; check the CDC SARS website at http://www.cdc.gov/ncidod/sars/.

Case Definition

The case definition for suspected SARS is subject to change, particularly concerning travel history; the most current definition can be accessed at http://www.cdc.gov/ncidod/sars/casedefinition.htm.

Respiratory illness of unknown etiology with onset since February 1, 2003, meeting the following three criteria:

OR:

Areas with Documented or Suspected Community Transmission of SARS

Peoples’ Republic of China (i.e., Mainland China and Hong Kong Special Administrative Region); Hanoi, Vietnam; and Singapore

Causative Agent

CDC reports that there is mounting evidence that a newly detected coronavirus as the most likely cause of SARS, but this is not yet confirmed. Coronaviruses are a common cause of mild to moderate upper-respiratory illness in humans and are responsible for approximately one third of common colds.

Mode of Transmission

Large respiratory droplets and direct contact appear to be the predominant modes of transmission; airborne and fomite transmission may also play a role. Although symptomatic individuals are infectious, it is not known how long before or after symptoms begin that patients with SARS might be able to transmit the disease to others.

Reporting

Notify the Vermont Department of Health @ 802-863-7240 or 800-640-4374 immediately of any patients who meet the above definition. Direction will be given on specific laboratory specimens for transport to CDC.

Clinical Presentation

The incubation period is typically 2 to 7 days (although a few cases suggest an incubation period up to 10 days). The illness generally begins with fever, often associated with chills and rigors and might be accompanied by other symptoms, including headache, myalgias and malaise. Some patients have mild respiratory symptoms at the onset of illness. At day 3 to 7 of illness, a respiratory phase begins, with non-productive cough and/or dyspnea, which may progress to cause hypoxia that is severe enough to require endotracheal intubation in approximately 10% to 20% of cases.

Chest radiographs are often normal during the febrile prodrome (and may remain so during the entire illness), but interstitial infiltrates, both local and generalized, may be seen during the respiratory phase. Consolidations can be seen on chest radiographs obtained in the later stages of SARS.

Complete blood counts may reveal a normal (or sometimes decreased) total white blood cell count, but the absolute lymphocyte count is often decreased. During the peak of the respiratory phase, leukopenia and thrombocytopenia (50,000 – 150,000/ul) is seen in approximately half of patients.

Other laboratory abnormalities include elevated creatine phosphokinase (as high as 3,000 IU/L) and hepatic transaminase levels (2 to 6 times the upper limit of normal). In most patients, renal function has remained normal.

The course of SARS has been highly variable, ranging from mild, self-limited illness to death. The case-fatality rate among persons meeting the current case definition of SARS is approximately 3%. The case definition being used for surveillance purposes in the United States is detecting many cases with milder illness than what has been reported internationally. As of April 4, 2003, there were no deaths reported in the United States. The majority of close contacts to SARS cases remain well, although some have reported a mild febrile illness without a respiratory component and others have developed SARS. Most secondary cases have occurred among healthcare workers who were not using adequate infection control precautions.

Triage and Screening

Healthcare workers who are the first point of patient contact (e.g., triage nurses) should be trained to recognize a potential case of SARS by screening individuals with fever and respiratory symptoms for:

A surgical mask should be placed on any patient meeting these criteria. Some facilities have found it helpful to, place a box of masks by the entrances likely to be used by persons seeking care, and a notice asking that persons with respiratory symptoms don a mask before they approach the triage nurse.

Healthcare workers should implement Standard, Contact and Airborne Precautions. When available, place the patient in an airborne infection isolation room, i.e.: negative pressure room, and use of N-95 (or equivalent) disposable particulate respirators. When particulate respirators are not available, healthcare workers evaluating and caring for a patient with suspect SARS should wear a surgical mask.

Diagnosis/Evaluation of Patients

Along with other appropriate tests for the patient’s condition, CDC recommends that initial diagnostic testing should include chest radiograph, pulse oximetry, blood cultures, sputum Gram’s stain and culture, and testing for viral respiratory pathogens, notably influenza A and B and respiratory syncytial virus (RSV). Clinicians should save any available clinical specimens (respiratory, blood, and serum) for additional testing until a specific diagnosis is made. CDC will perform testing for the newly identified coronavirus when the patient meets the clinical case definition for SARS. Please contact VDH to arrange this testing.

Refer to http://www.cdc.gov/ncidod/sars/specimen_collection_sars2.htm for collection and handling of specimens from suspect SARS cases.

Treatment

There are no recommendations for specific treatment. There have been anecdotal reports of ribavirin with or without corticosteroids being used. For severely ill patients, consultation with infectious disease specialists or the CDC can be arranged.

Infection Control Guidelines for Patients with Suspected SARS in the Outpatient Setting

If a suspect SARS patient is evaluated in an outpatient setting, the following infection control measures should be followed until ten days after the resolution of respiratory symptoms:

Additional guidance regarding SARS infection control in the ambulatory care setting is available at http://www.cdc.gov/ncidod/sars/ic.htm

Management of Household Contacts

Patients with SARS pose a risk of transmission to close household contacts. The duration of time before or after onset of symptoms during which a patient with SARS can transmit the disease to others is unknown, however patients are currently being asked to follow these isolation measures while they are symptomatic and for ten days following resolution of respiratory symptoms. The following infection control measures are recommended for patients with suspected SARS in households or residential settings.

Additional guidance regarding SARS close contact in households is available at

http://www.cdc.gov/ncidod/sars/ic-closecontacts.htm

Infection Control Guidelines for Patients with Suspected SARS in the Inpatient Setting

If a suspect SARS patient is admitted to the hospital, the following infection control measures should be followed:

If airborne precautions cannot be fully implemented, patients should be placed in a private room with the door closed and a portable HEPA filter. If N-95 particulate respirators are not available, surgical masks should be worn. Other information on appropriate infection control precautions for patients with suspected SARS can be found at http://www.cdc.gov/ncidod/sars/ic.htm

Management of Unprotected Exposures among Healthcare Personnel

Transmission to healthcare workers appears to have occurred after close contact with symptomatic individuals (e.g., persons with fever or respiratory symptoms) before recommended infection control precautions for SARS were implemented. Given the currently available information on the epidemiology of SARS in the United States, the following outlines interim guidance for the management of exposures to SARS in a healthcare facility.

Additional guidance on exposure management for healthcare workers can be accessed at the CDC website http://www.cdc.gov/ncidod/sars/exposureguidance.htm

Hospital Visitors

Close contacts (e.g., family members) of SARS patients are at risk for infection. Close contacts with either fever or respiratory symptoms should not be allowed to enter the hospital as visitors and should be educated about this policy. Keep in mind that persons close to the individual could have had a common source exposure and may be incubating the disease; ask about travel history in these people. Visitors should be educated about use of infection control precautions when visiting SARS patients and their responsibility for adherence to them.