Twitter Flu Map 2012 (image) Johns Hopkins University Caption This map indicates the prevalence of flu in the United States in the first week of January 2012, as measured by the volume of flu-related tweets. States with higher flu rates are colored in a darker red. Last year's flu affected relatively few Americans. Credit Mark Dredze/JHU Usage Restrictions None Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.