Bats can indeed transmit deadly diseases like rabies and Nipah to humans, though transmission is exceedingly rare and easily avoided. In the case of Ebola, bats have been too easily assumed guilty. A wide variety have been tested at outbreak locations. But, “Ebolavirus has yet to be isolated from bats, and no direct evidence links bats to Ebolavirus infection in humans.” (Spengler et al. 2016) Virologists still know “nothing about where it comes from and how it causes outbreaks.” (Kupferschmidt 2017).
A Terrifying Time for Bats By Merlin Tuttle
The past month has seen a virtual explosion of premature speculation presented as though it were now proven fact, much of it traceable to a single article titled, “Bats are global reservoir for deadly coronaviruses,” that appeared in the June 14, 2017 issue of Nature. We’ve already issued a Bat Flash alert responding to this article, and to predecessors, all apparently part of a single cleverly planned campaign.
Sensational speculation has become widely cited as fact1, with spin-off damage that will be exceedingly difficult to reverse. All who truly care about bats have cause to be deeply concerned.
Due to scary speculation attempting to link the SARS outbreak of 2002 to bats, bats have recently become central in the search for viruses2. Thus, rapid advances in viral detection alone may have caused major bias. Also, the number of viruses found in bats is not necessarily indicative of risk.2 Many viruses are innocuous or even beneficial,3 including some that are closely related to deadly ones.4 Finally, the paper in question is based on models, and models are notorious for mistaken conclusions, regardless of the amount of data analyzed.5
A far more meaningful analysis should have considered the historic rarity of viral spillover from bats to humans. Many media stories now claim bats to be the primary source of so-called “emerging infectious diseases” like Ebola, though most of these speculations remain unproven.6- 7
Proponents of such speculation still cannot explain why hundreds of bat biologists, millions of people who eat bats, and the millions more who share cities with huge bat colonies are no less healthy than others. They can’t explain why bats artificially infected with Ebola haven’t become contagious or why virologists haven’t even been able to find live virus in the thousands of bats examined. Certainly, like all other mammals, bats must be capable of harboring at least a few dangerous viruses. Nevertheless, bats still have one of our planet’s finest records of living safely with humans.1
Virologists are still doggedly pursuing the search for an Ebola reservoir in bats, as reported in the storytitled Hunting for Ebola among the Bats of the Congo in the June 1, 2017 issue of Science (Kupferschmudt 2017), apparently attempting to ignore mounting evidence pointing elsewhere. The record of unsubstantiated speculation, attributing Ebola to bats is long and becoming an embarrassment to good science.
By 2014, researchers had discovered that 10% of gorillas in Central Africa have antibodies to Ebola, demonstrating that exposure or infection is not uniformly lethal as previously reported (Reed et al. 2014). Because great apes were said to be highly susceptible, virologists had insisted they couldn’t serve as reservoirs. Instead they pointed to bats.
Response to Smithsonian story, “Can Saving Animals Prevent the Next Deadly Pandemic?” Merlin Tuttle
Lorraine Boissoneault’s story, Can Saving Animals Prevent the Next Deadly Pandemic?, is clearly well intended. However, when it comes to fruit bats and Ebola it is based on outdated speculation that threatens serious harm to a group of mammals that is already in alarming decline. For a summary of current knowledge of bats versus Ebola and other rare, but so-called emerging diseases, and their speculated association with bats, I refer you to my article in the current edition of Issues in Science and Technology, titled “Give Bats a Break.”
Diseases that are millions of years old, but that are just now being discovered due to their rarity, are being referred to as “emerging” as an apparent public relations ploy to make them sound more dangerous. And speculating associations with bats makes them even more scary, since many people already fear bats. This has proven unprecedentedly effective in gaining hundreds of millions of dollars in grants to support so-called virus hunters, who must continue speculating about potentially dire threats from bat diseases to keep their grants flowing.
Bats historically have one of the world’s finest records of living safely with humans, first in caves and thatched huts, then in log cabins.
Sensational National Public Radio Story Threatens Bats By Merlin Tuttle
Unfortunately, the normally objective and reliable NPR, in its broadcast interview titled, Why Killer Viruses Are On The Rise, has joined in spreading irresponsibly sensational fear of bats. The interview with a “virus hunter” is set in a Bornean rainforest. In the preamble, the announcer notes that, “It’s where deadly viruses hide out, waiting their chance to leap into a person and then spread around the world.”
At a time when bats and rainforests are both in alarming decline, and in desperate need of protection, the program goes on to portray them in the scariest of terms. The reporter notes that rainforests “have lots of crazy animals” that “have lots of crazy viruses” and explains that what the virus hunter “really wants is to catch a bat.”
When the first bat is caught it is described as cute, but the reporter quickly points out that, “bats are arguably one of the most dangerous animals in the world. They triggered the Ebola outbreak in West Africa, the pandemic of killer pneumonia back in 2003, that was called SARS, and they’re behind one of the viruses scientists think could cause the next big one, Nipah.” This is unproven speculation reported as fact. But it gets even worse.
Following years of headline speculation reporting bats to be the reservoir for Ebola, a review of current knowledge points elsewhere. This often fatal disease is caused by the Ebolavirus genus, which includes five species (Sudan, Zaire, Bundibugyo, Tai Forest and Reston virus). The geographical distribution of these species along separate river basins is inconsistent with a highly mobile source, such as bats, that easily cross basin borders. (more…)
Ebola: Bats Prematurely Blamed By Merlin Tuttle
If public health concerns were based on actual threats to human mortality, diseases speculated to be spread by bats would take a distant back seat. Even our beloved dogs are many times more dangerous than bats (1). Real killers, like consumption of over processed and contaminated foods dwarf any risks associated with animals (2).
Yet we squander millions of scarce public health dollars on witch hunts for rare diseases in bats, when those funds could save far more human lives if spent on reducing already proven killers such as obesity and environmental toxicants linked to escalating rates of cancer, heart disease, dementia and diabetes.
In recent years speculation linking scary diseases to bats has gained unprecedented media headlines and grants.
Merlin Tuttle’s Bat Conservation is the most recent contribution by Merlin Tuttle to the world of bats. With over 50 years of in-depth knowledge and experience Merlin Tuttle, renowned bat expert, educator and wildlife photographer founded MTBC with one true goal in mind; teaching the world to understand and appreciate the vital contributions bats make to human beings and the world we live in.