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Member Research & Reports

Member Research & Reports

Without Swift Influx of Substantial Aid, Ebola Epidemic in Africa Poised to Explode – Yale Modelers Findings

The Ebola epidemic already devastating swaths of West Africa will likely get far worse in the coming weeks and months unless international commitments are significantly and immediately increased, new research led by Yale School of Public Health predicts.

Microscopic view of the ebola virus

A team of seven scientists from Yale and the Ministry of Health and Social Welfare in Liberia developed a mathematical transmission model of the viral disease and applied it to Liberia’s most populous country, Montserrado, an area already hard hit. The researchers determined that tens of thousands of new Ebola cases — and deaths — are likely by December 15 if the epidemic continues on its present course.

“Our predictions highlight the rapidly closing window of opportunity for controlling the outbreak, and averting a catastrophic toll of new Ebola cases and deaths in the coming months,” said Dr. Alison Galvani, professor of epidemiology at the School of Public Health and the paper’s senior author. “Although we might still be within the midst of what will ultimately be viewed as the early phase of the current outbreak, the possibility of averting calamitous repercussions from an initially delayed and insufficient response is quickly eroding.

The findings are published in the October 24 issue of The Lancet Infectious Diseases journal.

The model developed by Dr. Galvani and colleagues projects as many as 170,996 total reported and unreported cases of the disease (representing 12 percent of the overall population of some 1.38 million people) and 90,122 deaths in Montserrado alone by December 15. Of these, the authors estimate 42,669 cases and 27,175 will have been reported by that time.

Much of this suffering — some 97,940 cases of the disease—could be averted if the international community steps up control measures immediately, starting October 31, the model predicts. This would require additional Ebola treatment center beds, a fivefold increase in the speed with which cases are detected, and allocating protective kits to households of patients awaiting treatment center admission. The study predicts that, at best, just over half as many cases (53,957) can be averted if the interventions are delayed to November 15. Had all of these measures been in place by October 15, the model calculates that 137,432 cases in Montserrado could have been avoided.

“The United States committed 1,700 new treatment center beds to affected West African countries in mid-September,” said Mr. Joseph Lewnard, a PhD student at Yale School of Public Health and lead author of the paper. “The failure to expand treatment center capacity in a timely manner means that current intervention requirements for Montserrado alone exceed this still-unmet commitment.”

There have been approximately 9,000 reported cases and 4,500 deaths from the disease in Liberia, Sierra Leone, and Guinea since the latest outbreak began with a case in a toddler in rural Guinea in December 2013. For the first time cases have been confirmed among health care workers treating patients in the United States and parts of Europe.

The National Institutes of Health funded the study.