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CDC adds new color to flu activity chart indicating highest levels of respiratory illnesses

Purple indicates areas with very high activity levels

Sick woman and man have cold, flu and high fever.

The Center for Disease Control (CDC) has added a new color to its flu activity level chart, indicating areas with very high levels of respiratory illnesses.

Purple on a map shows the highest level of ILI activity. According to the CDC, the system monitors respiratory illness, including fever plus a cough or sore throat, also referred to as ILI.

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According to week 43, the District of Columbia, Alabama, South Carolina and Tennessee are deemed very high for influenza-like illnesses.

For more information on ILI activity levels, click here.

Weekly Influenza Surveillance Report of week 43 (The Center for Disease Control (CDC))