The recent and successful fight to contain the Ebola virus in West Africa was helped in no small measure by the application of data analysis and mathematical models that accurately predicted how and where the disease was spreading and how to contain it.
The lessons learned from use of math models in the Ebola fight can now be applied to the explosive threat of the mosquito-born Zika virus, which has moved rapidly to the Eastern United States from Brazil and the Caribbean in recent months.
These are among the chief conclusions of a March 2016 symposium held in Senegal, West Africa, on “Modeling of Infectious Diseases with a Focus on Ebola.” The symposium was organized by Rutgers University’s Dr. Fred Roberts and Howard University’s Dr. Abdul-Aziz Yakubu at the request of the National Science Foundation. When first conceived, the workshop was organized around Ebola. However, by the time it was held, Zika became a key theme.
Roberts is director of CCICADA, the homeland security research group, and director emeritus of DIMACS, the Center for Discrete Mathematics and Theoretical Computer Science at Rutgers. Yakubu heads the CCICADA partner at Howard University and serves on CCICADA’s Executive Committee. This was the tenth workshop DIMACS has organized and held with researchers in Africa. Senegal, the workshop location, is close to the areas of West Africa hardest hit by the 2014 Ebola outbreak.
Value of Modeling
“The workshop examined how past disease outbreaks were contained, and then explored how the mathematical modeling of epidemiological data can help us understand and forecast disease-transmission dynamics,” Roberts said. “Modeling can also be used to track changing conditions on the ground and evaluate the effectiveness of interventions. These all connect to research being done at CCICADA.”
The symposium brought together 30 public health officials as well as mathematicians, biologists, ecologists and epidemiologists from both the US and numerous African countries to identify important modeling issues and to establish new collaborations on what might be needed in order to contain infectious-disease outbreaks before they become public health emergencies.
Participants included government officials from the Centers for Disease Control and Prevention (CDC), as well as researchers from Africa with first-hand involvement in the fight against Ebola.
One of those participants was Brad Greening, a former DHS Career Development graduate fellow with CCICADA, and currently the holder of a prestigious CDC Fellowship. Greening worked with the CDC team in Atlanta, GA, that employed mathematical models to predict where Ebola would spread next and how many people it would affect. CDC officials and Ebola responders eagerly consumed this data. It told them, for example, how many beds and lab tests would be needed—and where and when—to arrest history’s worst Ebola outbreak.
Roberts noted that Greening is a prime example of the new generation of homeland-security professionals whose careers have been launched by CCICADA, a DHS University Center of Excellence, which uses advanced data research and analysis to assist the US Department of Homeland Security (DHS) and related agencies in protecting the American people from natural and man-made threats.
Important to the success of the Ebola containment was the sheer and unprecedented magnitude of epidemiological data made available online to researchers and modelers by the World Health Organization (WHO) and health ministries of the most affected countries. Though modelers have analyzed ongoing epidemics before, such as the 2003 SARS epidemic and 2009 Swine Flu pandemic, they did not have access to such rich sources of data.
Dr. Michael Washington, a health systems specialist with the CDC, said the “largest and most influential” modeling results from the Ebola epidemic showed “the impact of what would happen if we did nothing to stop this outbreak.”
“These results also showed the outcome of delaying the international response, and how we could stop this outbreak if 70 percent of Ebola cases could be placed in Ebola treatment units, had effective isolation, and had safe burials,” Washington said, adding: “Not only did our model show what could and should happen, it actually showed what happened.”
Other workshop themes included the value of taking a cross-disciplinary approach to disease-intervention strategies, the central role of data, and the role of climate change in the spread of disease.
“We already know that mosquito-borne diseases such as malaria are found in areas such as the highlands of Kenya, where they were not seen before, due to changing climates,” said Roberts. “Could climate change now bring malaria to the United States?”
He said this issue is being studied by CCICADA researchers including Howard’s Yakubu, Dr. Asamoah Nkwanta of Morgan State University, and Dr. Nina Fefferman of Rutgers University (a workshop presenter).
The Senegal workshop was a satellite workshop to the Next Einstein Forum (NEF), hosted by President Macky Sall of Senegal, an international event highlighting science and education in Africa. NEF participants included some 1,000 invited dignitaries, including leading scientists, policymakers, business leaders, two featured heads of state, and science and education ministers from Africa and other countries. At the NEF, Dr. Roberts exchanged ideas for future research efforts with leaders from South Africa, Senegal, Tanzania, Cameroun, Rwanda, Germany, Canada, and many other countries.
Because of the importance of local engagement in making workshops in foreign countries succeed, Drs. Roberts and Yakubu also made contact with the faculty of Mathematics at the University Cheikh anta Diop of Dakar. The President of the University led a mini-symposium on modeling of infectious diseases that explored the value of joint US-African collaboration.