Epidemiology Lab Activity

Even though grades are due Monday, I'll try to get in a couple of posts this weekend to make up for the recent absence. It's been real busy at home and work these days.

First up, a new lab, which is one of the tasks that have consumed me recently. I've gone through three different editions as I piloted it with my three different LE classes and I still want to make modifications if I can get some help - maybe next year.

This is the classic contagious disease lab, and I've made it specific to HIV until someone complains about it. In the lab, students simulate exchanging bodily fluids (also simulated, of course) and track the spread of HIV in a "sexually active" community. Of course the kids then joke about whom they've "had sex with" which makes me a little nervous about how other adults will react to the simulation, but I believe in confronting the reality on the ground - over 60% of high schoolers have had sexual intercourse by the time they are seniors. If I can influence them to practice abstinence or safer sex by demonstrating how STIs can spread, then I will take the chance of a parent complaining - better to ask forgiveness than permission in the bizarro world of public education.

Epidemiology Lab

You can change a bit of the introductory text and make it a generic contagious disease lab.

The part I need help with is a method for determining the original infected individual and verifying the conclusion. My students did a great job of figuring out the first part on their own, using their own logic and methods. The difficulty is then verifying their hypotheses by being able to trace all infected individuals back to the index case. At this point you have to take into account the sequence of infection among many individuals who have had multiple partners - it's a lot of detail to try to keep in one's head, and I don't yet have a spreadsheet or flowchart model for organizing it - but I'm working on it.

UPDATE

I've modified the class data table, making separate columns for each partner. Once you have decided who the index case is, you then use the index case as your starting point and draw lines of "descent" from the index case to each infected individual. If I have time I'll post a sample later next week.

UPDATE II (4/5/07)

I DID hear from a few parents about this lab at parent/teacher conferences last week - all positive. Of course that's a pretty small and probably biased sample - the kids who are comfortable going home and telling their parents about the lab are the ones whose parents would most likely be supportive of their children being exposed to this kind of information in this manner. Still, it's encouraging when parents express unsolicited support for what you're doing in the classroom.