Mapping your sickness

A mashup, in online talk, is a site or application that combines content from several sources. Google Map is a favorite matrix for mashups and one of the most intriguing (for us) is one called "Who is Sick?" It's a voluntary geographically-based reporting system for sickness:

A new Google Maps mashup helps you track colds, flus and other bugs in your community.

Start by entering your city or ZIP code to see if other users have reported any sicknesses. You'll see a Google map dotted with icons that indicate symptoms like runny nose, cough, fever and headache. You can also post your own illness, complete with your age, sex, symptoms and any comments you care to add (the information is totally anonymous). The site includes statistics and discussion forums for individual states and cities. (Lifehacker)

Here's what it looks like (for Milwaukee, Wisconsin):

The finest geographic resolution seems to be zip code, but for contagious disease in the community this may be sufficient. But what would you use such a system for? Well, you could try to use it to see when illnesses are increasing in your area or whether what you have is plaguing others. However you are looking at all sorts of illnesses and seeing when a particular cause is becoming more prevalent might be difficult. You'd be looking for a possibly weak signal in a lot of noise. If the signal were strong, you probably don't need this website to tell you. Even comparing illness at one time with another time is tricky. The numbers will bounce around a lot, vary from season to season and week to week and you might have a lot of difficulty figuring out if any differences were significant (I'm not using this in the statistical sense but the public health sense). Even comparing two cities is difficult. You are only seeing cases, not the underlying population at risk. If the population is much greater in one place than another there could be many more cases but less risk for an individual.

These are only a few of the difficulties. But it sure as hell is a neat idea.