Bat Flash! Respond to Reuters News Release Blaming Bats for New Ebola Outbreak

By Merlin Tuttle
5/15/18

 

I share Benoit Nyemba and Fiston Mahamba’s concern regarding a potential resurgence of Ebola in the Democratic Republic of Congo, as Reuters News reported on May 8. Nevertheless, continuing to blame bats as the source is likely to reverse conservation progress essential to  ecosystem health (Lopez-Baucells et al. 2018) and delay successful Ebola prevention. Understanding the true source is essential.

A male straw-colored fruit bat (Eidolon helvum). This is the species that was first erroneously blamed for infecting the two-year-old toddler identified as the index case that triggered the 2013-2014 Ebola outbreak. In the end no one could explain how a bat that never enters buildings and has a three-foot wingspan could have contacted a toddler without anyone knowing about it!

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).

Early Ebola outbreaks were traced to human consumption of infected chimpanzees, gorillas and duikers (Rouquet et al. 2005), though these animals were believed to be too susceptible to serve as reservoirs (Wittmann et al. 2007).

Nevertheless, subsequent research revealed Ebola antibodies in 10 percent of gorillas (Reed et al. 2014)  and in 18.7 percent of pygmies (Mulangu et al. 2016), demonstrating that exposure is not as uniformly lethal in either great apes or humans as previously believed. Nancy Sullivan, a viral immunologist with the Vaccine Research Center at the National Institutes of Health, notes that “there is little evidentiary data to document widespread death of apes from Ebola” (Pedris 2017). These discoveries provide potential breakthroughs in the hunt for reservoirs.

The preponderance of evidence now points to sources other than bats (Leendertz 2016). There are four African species of Ebola: Sudan, Zaire, Bundibugyo, and Tai Forest Ebola. The geographical distributions are along separate river basins, and this is inconsistent with a highly mobile source, such as bats. Bats easily cross river basins.  Experimentally infected bats can survive infection, as often cited, but they also show no evidence of viral shedding and are unlikely transmitters (Paweska et al. 2016).

Current claims that bats are the most likely sources of Ebola appear to have gained momentum from careless reporting of the index case for the 2013-2014 outbreak. The first team to investigate speculated a fruit bat origin, despite a complete lack of supporting evidence, as noted by a second team who also found no evidence of Ebola in a large sample of both fruit and insect-eating bats, but still speculated an insect-eating bat origin, whereupon the roost was burned with the bats inside (Saez et al. 2015).

It now seems likely that the disproportionate epidemiological focus on bats may have delayed much needed progress (Tuttle 2017) while doing great harm to the conservation of bats (Lopez-Baucells et al. 2018). Bats are economically and ecologically invaluable, but they also rank among our planet’s most endangered wildlife (Voigt and Kingston 2015). It’s time to halt the bias. People don’t tolerate animals they fear, and we need to know where Ebola is coming from.

 

TAKE ACTION!

Our combined voices can make a difference. Choose any or all means of contact to reach out to the staff at Reuters News and politely share your opinion in your own words. Editors do take notice. Remember, your response can be very simple such as, “I don’t appreciate premature speculation that creates needless fear of bats.” Editors just need to know you like or dislike an article in order for you to have impact. It’s numbers that count. Bats need all of you!

 

Hundreds of thousands of Straw-colored fruit bats (Eidolon helvum) beginning their evening departure from a city park in Ivory Coast, Africa. Cities often provide the only homes safe from commercial hunters who sell the bats for people to eat. Despite such large numbers having lived in close association with humans throughout recorded history, they have not caused any known disease outbreaks. Their remarkable safety record casts grave doubt on recent speculation of their being dangerous spreaders of Ebola.

References

Kupferschmidt, K. 2017. Hunting for Ebola among the bats of the Congo.  Science, June 1.

Leendertz, S.A.J. 2016. Testing new hypotheses regarding ebolavirus reservoirs. Viruses 8(2), 30; doi:10. 3390/v8020030.

Lopez-Baucells, A., Rocha, R. and A. Fernandez-Llamazares. 2018. When bats go viral: negative framings in virological research imperil bat conservation. Mammal Review 48(1): 62-66.

Mulangu, S., M. Borchert, J. Paweska, A. Tshomba, A. Afounde, A Kulidri, R. Swanepoel, J.J. Muyembe-Tamfum, and P. Van der Stuyft. 2016. High prevalence of IgG antibodies to Ebola virus in the Efe pygmy population in the Watsa region, Democratic Republic of the Congo. BMC Infec. Dis. June 10;16;263

Paweska, J.T., N. Storm, A.A. Grobbelaar, W. Markotter, A. Kemp, and P.J. van Vuren. 2016. Experimental inoculation of Egyptian fruit bats (Rousettus aegyptiacus) with Ebola virus. Viruses 8(2):29.

Pedris, L. 2017. Going viral: How advancements in Ebola disease detection in wild apes can help to prevent dangerous outbreaks. Mongabay, May 4.

Reed, P.E., S Mulangu, K.N. Cameron, A.U. Ondzie, D. Joly, M. Bermejo, P. Rouquet, G. Fabozzi, M. Bailey, Z. Shen, B.F. Kele, B. Hahn, W.B. Karesh, and N.J. Sullivan. 2014. A new approach for monitoring Ebolavirus in wild great apes. PLOS, Sept. 18, https://doi.org/10.1371/journal.pntd.0003143.

Rouquet, P. J-M. Froment, M. Bermejo, A. Kilbourn, W. Karesh, P. Reed, B. Kumulunqui, P. Yaba, A. Delicat, P.E. Rollin, and E.M. Leroy. 2005. Wild animal mortality monitoring in human Ebola outbreaks, Gabon and Republic of Congo, 2001-2003. Emerg. Infect. Dis. 11(2):283-290.

Saez, A.M., S. Weiss, K. Nowak, V. Lapeyre, F. Zimmermann, A. Dux, H.S. Kuhl, M. Kaba, S. Regnaut, K. Merkel, A. Sachse, U. Theisen, L. Villanyi, C. Boesch, P.W. Dabrowski, A. Radonic, A. Nitsche, S.A. J. Leendertz, S. Petterson, S. Becker, V. Krahling, E.Couacy-Hymann, C. Akoua-Koffi, N. Weber, L. Schaade, J. Fahr, M. Borchert, J.F. Gogarten, S. Calvignac-Spencer, and F.A. Leendertz. 2015. Investigating the zoonotic origin of the West African Ebola epidemic.

Tuttle, M.D. 2017. Give bats a break. Issues in Science and Technology. Spring edition.

Voigt, C.C. and T. Kingston (eds). 2016. Bats in the Anthropocene: Conservation of bats in a changing world. DOI 10,1007/978-3-319-25220-9_1.

 

 

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A Terrifying Time for Bats

A Terrifying Time for Bats
By Merlin Tuttle
7/2/17

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.

An adult male Straw-colored fruit bat (Eidolon helvum) from Kenya. This is the species first blamed for the “index case” of Ebola in the 2014 outbreak in West Africa. The species was soon exonerated. In fact, it is so resistant to Ebola that it is an unlikely source. Recent studies suggest a source other than bats.

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

Thai women collecting guano in Rakang Cave. These women spend countless thousands of hours sweeping up the guano and bagging it while being pooped on by hundreds of thousands of fruit- and insect-eating bats high overhead and report no ill effects.

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

Children begin helping collect guano almost as soon as they can walk.

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Behind the Latest Ebola Story in Science

By Merlin Tuttle
6/7/17

Virologists are still doggedly pursuing the search for an Ebola reservoir in bats, as reported in the story titled 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.

A hammer-headed bat (Hypsignathus monstrosus) eating a rose apple (Eugenia jambos) in Ivory Coast. This species is now the central focus of the Ebola reservoir search reported in Science. It is a key seed disperser in areas in need of reforestation.

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Response to Inappropriate Coverage of Bats and Ebola in Smithsonian Publication

Response to Smithsonian story, “Can Saving Animals Prevent the Next Deadly Pandemic?”
Merlin Tuttle
5/9/17

 

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.

Hundreds of thousands of Straw-colored fruit bats (Eidolon helvum) beginning their evening departure from a city park in Ivory Coast, Africa. Cities often provide the only homes safe from commercial hunters who sell them for people to eat. Despite such large numbers having lived in close association with humans throughout recorded history, they have not caused disease outbreaks. Their remarkable safety record casts grave doubt on recent speculation of their being dangerous carriers of disease.

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BAT FLASH! Sensational NPR Story Threatens Bats

Sensational National Public Radio Story Threatens Bats
By Merlin Tuttle
2/14/17

 

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.

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UPDATE!  Ebola virus researchers considering alternative reservoir hypotheses, bats unlikely

Hundeds of thousands of Straw-colored fruit bats (Eidolon helvum) emerging from their roost in a city park in Abidjan, Ivory Coast. Such huge colonies have occupied African cities throughout recorded history without causing disease outbreaks.
Hundreds of thousands of Straw-colored fruit bats (Eidolon helvum) emerging from their roost in a city park in Abidjan, Ivory Coast. Such huge colonies have occupied African cities throughout recorded history without causing disease outbreaks.

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…)

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Ebola: Bats Prematurely Blamed

Ebola: Bats Prematurely Blamed
By Merlin Tuttle
1/14/16

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.

An adult male straw-colored fruit bat (Eidolon helvum), the species most often blamed for Ebola.

In recent years speculation linking scary diseases to bats has gained unprecedented media headlines and grants.

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