Lessons Learned From Nigeria: Fast Action Stops Ebola

Swift implementation of control interventions tamped down an outbreak of Ebola in Nigeria and stopped the disease from spreading widely, according to research published October 14, 2014 in the journal Eurosurveillance.

“Rapid and forceful control measures are necessary as is demonstrated by the Nigerian success story. This is critically important for countries in the West African region that are not yet affected by the Ebola epidemic, as well as for countries in other regions of the world that risk importation of the disease,” said Gerardo Chowell, senior author of the paper and an associate professor at the Arizona State University.

Chowell, Lone Simonsen, PhD, a research professor of global health at Milken Institute School of Public Health at the George Washington University, and a multi-center team of scientists did the research. The team analyzed up-to-date epidemiological data of Ebola cases in Nigeria as of October 1, 2014, in order to estimate the case fatality rate, proportion of health care workers infected, transmission progression and impact of control interventions on the size of the epidemic.

The team found that the rapid control of the outbreak in Nigeria was likely facilitated by the early detection of the first case; intense tracing of people who might have come into contact with the infected individual; and isolation of all those who subsequently developed Ebola.

The team used a dynamic disease mathematical modeling strategy to project the size of the outbreak in Nigeria that could have happened if control interventions had been put in place during various time periods, ranging from 3 to 50 days.  

The researchers found that the number of Ebola cases in Nigeria ranged from 15-106 cases when interventions are put in place rapidly as compared to up to thousands of cases if the interventions are delayed by 50 days.  

“There is brief window of time when a rapid and forceful intervention in terms of relentless contact tracing and isolation pays off handsomely,” Simonsen says. “As our modeling in this paper shows, if intervention is deployed rapidly transmission is effectively halted and the outbreak can be halted.”

Indeed, as of September 2014 there were no new Ebola cases reported in Nigeria and the World Health Organization will, if all goes well, declare the country Ebola-free. In contrast, the epidemic continues to rage in the West African countries of Guinea, Sierra Leone and Liberia with more than 7,000 cases and counting as of October 1, 2014.

Other authors on the report include University of Pretoria Senior Scientist Folorunso Oludayo Fasina; and Cécile Viboud at the National Institutes of Health.

Read the report.