I found out at the Tabitha Health Clinic in Kibera, the city’s largest informal settlement, meeting with a health worker named Emma who uses data to save lives.

In a project with the U.S. Centers for Disease Control and an organization called Carolina for Kibera, the Tabitha Clinic is working closely with the population in one neighborhood in Kibera. Health workers go house to house, collecting data from every resident every two weeks. The data is fired back to a central system via palm held devices.

When the staff saw a spike in the number of cases of diarrhea last year, they got worried about the possibility of a cholera outbreak. But as soon as the lab confirmed a cholera case, they visited the home of the infected individual, treated the members of the household, and conducted counseling sessions in the surrounding area. In the end, there were only four cases of cholera in the neighborhood.

It’s impossible to say how many people would have gotten cholera without that immediate intervention, but other slum areas have had cholera outbreaks of 1,000 cases, so it’s logical to assume that the use of real-time data saved lives and prevented a significant amount of misery."