The Ebola virus currently poses the greatest threat to the survival of great apes, conservationists have warned, after killing an estimated third of the world’s gorillas and chimpanzees since the 1990s, reports the Independent.
The unprecedented current Ebola epidemic in West Africa has killed some 8,641 people, according to data from the World Health Organization, while the first batch of GlaxoSmithKline’s experimental Ebola vaccine was expected to arrive in Liberia today.
But conservationists have suggested a vaccination could also prove helpful in tackling the threat the virus poses to our closest cousins.
Meera Inglis, a Conservation Policy PHD student at the University of Sheffield, said: “At this moment in time Ebola is the single greatest threat to the survival of gorillas and chimpanzees.”
She goes on to suggest while vaccination could help as “a short-term strategy” to tackle the virus in apes, a longer-term strategy could focus on restoring forest habitat, “as larger forested areas would reduce the chances of infected animals coming into contact with one another.”
According to Al Jazeera America, Ebola now ranks along with poaching and deforestation as the major threats to Africa’s ape population.
“In the last two decades, Ebola has been responsible for several catastrophic great ape population declines,” writes Ria Ghai of the Jane Goodall Institute of Canada. As an example, Ghai cites an Ivory Coast chimpanzee community reduced by half in an outbreak of Ebola in the Tai Forest that lasted two years.
“When all Ebola mortality is summed together,” according to Ghai, “an estimated one-third of the world’s gorillas and chimpanzees have been killed by this disease.”
And the widespread primate outbreaks can increase the risk to humans. Contact with the dead bodies of chimps in Gabon “likely led to the three secondary epidemics in humans” between 1994 and 1997, according to the Goodall Institute reports Al Jazeera America.
According to the WWF (World Wildlife Fund), a 1994 Ebola outbreak in Mikébé, in northern Gabon, “wiped out the entire population of what used to be the second largest protected population of gorillas and chimpanzees in the world.”
In 2006, meanwhile, a study published in the journal Science suggested 5,000 gorillas were killed in Gabon and Congo by the Zaire strain of Ebola in 2002 and 2003.
Like with previous outbreaks, the current human epidemic began with animal contact. Ebola has so far proven unsustainable in human populations without an animal vector. The fear is that as human populations expand and wildlife habitats dwindle, contact with infected animals will become more frequent.
Cath Lawson, WWF-UK’s Regional Officer – East Africa, told the Independent: “Although scientists project that a human approved Ebola vaccine might be available early this year – if and when a vaccine is available, there is presently no feasible method to vaccinate by injection more than a handful of wild great apes, thus potentially protecting only a minimal portion of overall great ape numbers.”
Lawson added, “Other methods of vaccine delivery are being explored, including ‘self-disseminating’ vaccines, and would ideally be less invasive and potentially affect many more individuals within a given population. At present, we are forced to rely on natural barriers (e.g., rivers, human settlements, possibly roads, etc.) to halt the spread of Ebola and its passing from population to population. Indeed, suggestions have been made to secure these barriers by, for example, periodically clearing narrow rivers where occasional tree-falls render them traversable to great apes.”
There are still an estimated 100,000 gorillas and between 150,000 and 250,000 chimpanzees left in the wild — alongside more than seven billion humans.
[Image via Wikimedia]