Reading the heat map

• Area colors: green Low, yellow Moderate, orange Elevated, red High reported activity.
• Gray: Insufficient data. There isn't enough recent official data to classify the area. It never means there are no infections.
• Ringed markers: official CDC travel notices or WHO outbreak reports. They show where a notice applies; they are not an activity level.
• Zoom into the United States for states, and further for county emergency-visit trends (COVID-19, flu and RSV).
• Use the filters at the top to show one disease. All diseases shows the highest level of the respiratory diseases with data.
• Press play to step through recent weeks.

Tap any area or marker to see a short summary. Tap Details for every data series, its trend and its source.