On December 21, 2014, Jodi Vanden Eng, MS ’04, a research mathematical statistician with the Center for Global Health at the U.S. Centers for Disease Control and Prevention, flew to Sierra Leone to begin a six-week deployment in Freetown. The Ebola epidemic was at its peak, with some 500 new cases being reported weekly. Although Vanden Eng had been to Sierra Leone four times before to work on malaria prevention, nothing prepared her for what she found when she landed. As Vanden Eng recalls:

“Instead of people holding hands and hugging in general social situations, there were nods and faint smiles. Curfews at night prevented social gatherings. Roadblocks with hand-washing stations and fever checks had become routine. And drivers yielded to ambulances and any vehicle with EBOLA RESPONDER on the windshield.

A colleague and I were given the task of assessing the surveillance process and data flow for the country’s Ebola response. This seemed insurmountable. How do you describe the surveillance and information systems of a newly introduced disease for an entire country? How do you account for the variation between districts, partners, and nongovernmental organizations? But it had to be done, so we developed a small standardized set of questions.

We visited Ebola response centers in several districts and assessed the data flow from beginning to end from the patient’s perspective, including alerts, ambulances, case management, labs, quarantine, holding and treatment centers, contact tracing, and burials. We assessed information technology infrastructure and resources.

I sometimes had mixed feelings about my work. When people are dying, data collection is often an extremely low priority—and rightfully so. Nonetheless, real-time data are invaluable for coordinating response efforts. Not only do data describe the epidemiology of the disease, but they also identify areas with the greatest needs and allow donors to direct aid and resources efficiently and cost-effectively.

Working on data assessment allowed me to see the big picture of the outbreak. I saw public health workers tirelessly visiting every health center to train and retrain staff on standard infection-control procedures. I saw survivors who stayed on at treatment centers to provide care for other patients. I saw people hold special, unplanned meetings to figure out where to place newly orphaned children, or how to care for a pregnant woman going into labor while in quarantine. I saw a volunteer set up a village hotline to enable families to get feedback about their ill loved ones. Although these types of efforts could not be measured with data, they were crucial to the response.

Nearly one year after my deployment and two years from the start of the outbreak, it felt really gratifying to hear the World Health Organization declare Sierra Leone Ebola-free on November 7, 2015. It was especially gratifying to know that the efforts of so many people who tried to prevent the disease from spreading—including those who lost their lives—were not in vain.”