April 20, 2003, 6:30 PM ET

The previous CDC SARS case definition (published April 16, 2003) has been updated as follows:

* Reported U.S. cases of SARS will be classified as suspect or probable based on the criteria outlined below.

* Toronto, Canada has been added to the areas with documented or suspected community transmission of SARS.

Suspect Case

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

* Measured temperature greater than 100.4??F (greater than 38??C) AND

* One or more clinical findings of respiratory illness (e.g., cough, shortness of breath, difficulty breathing, or hypoxia) AND

* Travel? within 10 days of onset of symptoms to an area with documented or suspected community transmission of SARS (see list below; excludes areas with secondary cases limited to healthcare workers or direct household contacts) OR

Close contact* within 10 days of onset of symptoms with a person known to be a suspect SARS case.

Probable Case

A suspect case with one of the following:

* Radiographic evidence of pneumonia or respiratory distress syndrome

* Autopsy findings consistent with respiratory distress syndrome without an identifiable cause

Travel includes transit in an airport in an area with documented or suspected community transmission of SARS.

Areas with documented or suspected community transmission of SARS: People's Republic of China (i.e., mainland China and Hong Kong Special Administrative Region); Hanoi, Vietnam; Singapore; and Toronto, Canada.

*Close contact is defined as having cared for, having lived with, or having direct contact with respiratory secretions and/or body fluids of a patient known to be suspect SARS case.