In the latest example of technology using syndromic surveillance, “Sickweather” uses self-reports of illness on social media sites to help map where illnesses are occurring. According to Mashable, the system scans over 600,000 records on Facebook and Twitter every month to map “sick zones”.
The creator likens the system to Waze, the GPS navigation system that helps to navigate you around accidents and traffic.
The concept is interesting but it is difficult to see how it could work. Unlike accidents, people migrate. Also the epidemiological properties of a disease are important. Some disease will be highly contagious while others are less so.
Take the example screenshot posted below. The information about flu being reported isn’t necessarily actionable information. Do I know if the infected person is still there? What if it is a multistory building? Just because I walk along that street does not mean I am in danger.
The service also suffers from an issue that plagues (no pun intended) epidemiologist. While the system, like Google Flu Trends, uses syndromic surveillance and can thus make interferences before data is reported to health authorities, there is still the issue that people shed the influenza virus before they are symptomatic. Thus, even if the system can track every person with symptoms of a disease, it will always underreport in terms of actual number of infectious people.
Still though the idea is intriguing and another example of how technology can be used to protect health. What may be helpful to know is what geographic locations are experiencing higher than normal levels of an illness.
See also: Influenzanet