Here’s the CDC’s latest SARS case definition
The Centers for Disease Control and Prevention (CDC) recently updated its case definition of severe acute respiratory syndrome (SARS) so that it is different from what EDs used in the last influenza season.
The exclusion criteria have been revised to allow exclusion of cases with a convalescent-phase serum sample (i.e., collected more than 28 days after symptom onset) that is negative for antibody to SARS-associated coronavirus (SARS-CoV).
Testing results from serum previously collected between 22 and 28 days after symptom onset are acceptable and will not require collection of an additional sample more than 28 days after symptom onset.
The case classification has been revised to exclude probable and suspected SARS cases with convalescent-phase serum samples that are negative for antibodies to SARS-CoV.
These are the CDC’s clinical criteria for diagnosing SARS:
• Asymptomatic or mild respiratory illness.
• Moderate respiratory illness:
— temperature of greater than 100.4 degrees Fahrenheit (greater than 38 Celsius); and
— one or more clinical findings of respiratory illness (e.g., cough, shortness of breath, difficulty breathing, or hypoxia).
• Severe respiratory illness:
— temperature of greater than 100.4 degrees Fahren-heit (greater than 38 degrees Celsius); and
— one or more clinical findings of respiratory illness (e.g., cough, shortness of breath, difficulty breathing, or hypoxia); and one of these symptoms:
1. radiographic evidence of pneumonia;
2. respiratory distress syndrome;
3. autopsy findings consistent with pneumonia or respiratory distress syndrome without an identifiable cause.
The CDC definition includes this note: "Factors that may be considered in assigning alternate diagnoses include the strength of the epidemiologic exposure criteria for SARS, the specificity of the diagnostic test, and the compatibility of the clinical presentation and course of illness for the alternative diagnosis."
For measuring a patient’s temperature, the CDC says a measured documented temperature of greater than 100.4 degrees Fahrenheit (greater than 38 degrees Celsius) is preferred. However, clinical judgment should be used when evaluating patients for whom a measured temperature of greater than 100.4 degrees Fahrenheit (greater than 38 degrees Celsius) has not been documented. Factors that might be considered include patient self-report of fever, use of antipyretics, presence of immunocompromising conditions or therapies, lack of access to health care, or inability to obtain a measured temperature.
"Reporting authorities should consider these factors when classifying patients who do not strictly meet the clinical criteria for this case definition," the CDC says.
The Centers for Disease Control and Prevention (CDC) recently updated its case definition of severe acute respiratory syndrome (SARS) so that it is different from what EDs used in the last influenza season.You have reached your article limit for the month. Subscribe now to access this article plus other member-only content.
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