Villain or hero? Bats may be key to curing Ebola, scientists say
"If we can understand how they do it then that could lead to better ways to treat infections that are highly lethal in people and other mammals," said Olivier Restif, a researcher at the University of Cambridge in Britain, as quoted by Reuters.
Scientists believe the bats’ ability not to suffer from Ebola is closely connected with their ability to fly. This skill requires an extremely high metabolism which can be destructive for a living being. According to a new hypothesis, bats developed a special mechanism to prevent the destruction of their body from their super-active metabolism. Moreover, they keep their immune system permanently active, unlike humans, so they react to the virus before its concentration reaches a response threshold.
"If our immune system behaved the way a bat's did...then maybe some of these viruses wouldn't be a problem anymore,” said Michelle baker of the Australian Animal Health Laboratory at Australia's National Science Agency.
Baker, along with colleagues, found that bats have a very large amount of genes for repairing DNA damage, hinting at a link between flying and immunity.
"(This) raises the interesting possibility that flight-induced adaptations have had inadvertent effects on bat immune function and possibly also life expectancy," Baker said.
Bats live enormously long compared to other animals of their size, some of them over 40 years.
"We are just at the beginning," Baker said. "But if we can understand how bats are dealing with these viruses and if we can redirect the immune system of other species to react in the same way, then that could be a potential therapeutic approach."
The impact of Ebola on people is mainly the result of the activation of the immune system, and not the virus itself. It is activated when the virus reaches dangerous levels. As a result, the immune system overreacts, and thus can damage the patient. In the case of Ebola, it leads to internal and external bleeding, decreased kidney and liver function, and ultimately, in many cases, death.
Fruit bats are under suspicion of being a natural host of Ebola since its discovery in 1976. However, it is possible for people to become infected indirectly; for instance, the virus can be transmitted from bats to monkeys via half eaten fruit. People could then become infected after coming into contact with the animals’ blood. Undercooked bat stew has been blamed, too.
Some specialists believe the actual outbreak is largely the result of public health failures.
"What is happening now is a public health disaster rather than a problem of wildlife management," said Marcus Rowcliffe of the Zoological Society of London (ZSL).
Despite their role in the Ebola outbreak, bats help a lot of people in Africa survive. Cooked bats are a traditional meal in many regions of the continent. Though it is possible to become infected while hunting, thoroughly cooked bat meat is regarded as safe.
"In the long run it would be sensible to see people moving away from hunting bats but in the short term they provide an important source of food," said Rowcliffe of ZSL. "Essentially, wild meat is a good, healthy product. People in Britain eat venison and rabbit, and in many ways it's no different to that."