The international response to the Ebola epidemic in West Africa is “grossly inadequate,” coming too late and providing too few beds for the sick to stop the soaring number of cases and deaths, Yale scientists say. The team warns that unless international commitments are significantly and immediately increased, the Ebola outbreak – already devastating the three hardest-hit countries – will soon spiral into a crisis of unprecedented scale.
The study, published online ahead of print in The Lancet Infectious Diseases, models the public health response in Montserrado, Liberia, against the spread of the virus and underscores the urgency of the dire situation.
“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,” warns Dr. Alison Galvani, senior author and professor of epidemiology at Yale School of Public Health.
As of October 19, nearly 4,900 people have died of the Ebola virus and almost 10,000 cases have been confirmed, the World Health Organization reported this week. More than half of those deaths – 2,705 – and the largest share of cases have been reported in Liberia, an economically fragile nation with an exiguous public health infrastructure. Before the outbreak, Liberia had only three healthcare workers per 10,000 people and 51 doctors serving the entire country; since the outbreak began, these numbers have hit rock-bottom, with some reports suggesting that 95 percent of Liberia’s doctors have fled the country.
While international aid is slowly trickling into the area, the scientists behind this latest study say that current efforts will not bring the outbreak under control.
“Perhaps most alarming is that, although we might still be within the midst of what will ultimately be viewed as the early phase of the current Ebola virus disease (EVD) outbreak, the window of opportunity for aversion of calamitous repercussions from an initially delayed and insufficient response is diminishing rapidly,” the authors write. “Our predictions suggest that current commitments are grossly inadequate to provide beds for all affected individuals, even only considering near-term growth of the epidemic in Montserrado.”
Up to 12% of Montserrado’s 1.38 million residents could be infected with Ebola by Dec. 15
In the new study, the team of seven scientists from Yale University 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 county, Montserrado, home to the capital city of Monrovia and among the hardest-hit regions in the country. Using epidemiological data from the area, the researchers estimated the reproductive number to be 2.5, meaning that each person infected with Ebola (index case) is transmitting the virus, on average, to 2.5 other people (secondary cases).
The model projects that if no additional measures are taken, there will be more than 170,000 total reported and unreported cases of the disease – representing 12 percent of Montserrado’s overall population of 1.38 million people – and more than 90,000 deaths by December 15.
Much of this suffering — nearly 98,000 cases of the disease — could be averted if the international community steps up control measures immediately, the model predicts. This would require at least 4,800 additional Ebola treatment center beds, a fivefold increase in the speed with which cases are detected, and allocation of protective kits to households of patients awaiting treatment center admission. And that’s just to prevent those 98,000 cases in Montserrado; it’s not enough to stop the outbreak in its tracks, and it doesn’t include the rest of Liberia, or Guinea or Sierra Leone where the outbreak is also raging.
To prevent those 98,000 cases, the aid would need to be sent by October 31, according to the researchers. To wait until November 15 would mean that the same amount of aid could only prevent 54,000 cases at best. The same aid, if it had been sent on October 15, could have prevented 137,000 cases. That’s because every West African who contracts Ebola infects two people, on average. Then each of those two cases infects two more people, and so on, making the outbreak grow exponentially. Delivering aid sooner rather than later interrupts the exponential growth curve, preventing more cases in the long run.
‘Current global health strategy is woefully inadequate’
At this point, Liberia is a long way from meeting the needs identified in the analysis. The US, which is leading the response in Liberia, has promised 17 new treatment centers with beds for 1,700 patients in Montserrado. According to the WHO, Liberia had only 620 Ebola beds as of October 15 — far short of the 4,800 beds currently needed, even when the US aid is taken into account. “Findings of our analysis suggest that the capacity of Ebola virus disease treatment centers needed to reduce the severity of the current outbreak greatly exceeds current international commitments,” the authors write.
“The current global health strategy is woefully inadequate to stop the current volatile Ebola epidemic,” co-author Frederick Altice, M.D., professor of internal medicine and public health added. “At a minimum, capable logisticians are needed to construct a sufficient number of Ebola treatment units in order to avoid the unnecessary deaths of tens, if not hundreds, of thousands of people.”
The authors note that their model, based on data from mid-October, may not represent the current situation in Liberia. However, as Drs. David Fisman and Ashleigh Tuite, experts in epidemiology at the University of Toronto (UT), pointed out in a commentary in The Lancet Infectious Diseases, the growth of the epidemic so far has fit “so well with mathematical epidemiological idea that it seems torn from the pages of a text book,” providing support for the model’s accuracy.
“The key take-home message for readers is this: we have no time to waste,” the UT researchers write. “The urgency of timely intervention in the Ebola epidemic cannot be overstated,” they say, warning that the already devastating outbreak “threatens to evolve into a health and humanitarian catastrophe of historic scope.”
“The new [findings] show that intervention will only be meaningful if it is timely,” the researchers write, “and so far it has not been.”