Keep track of Flu trend on Google Flu Trends http://www.google.org/flutrends/
We’ve found that certain search terms are good indicators of flu activity in the United States. Google Flu Trends uses aggregated Google search data to estimate possible flu activity at a state level in near real-time.
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In response to inquiries from public health officials regarding the current swine flu outbreak, we built an experimental model for Mexico. You’ll see our unverified estimates on the Experimental Flu Trends for Mexico page. We hope this may shed additional light on possible flu activity in states in Mexico.
Unlike Google Flu Trends for U.S., Experimental Flu Trends for Mexico was not built using historical data on flu symptoms. This means the models have not been checked against actual historic flu data from Mexico and thus the estimates you see for Mexico are unverified. The models for Mexico are based on aggregated search queries likely to be associated with influenza-like illness (ILI).