Prox Authors & Ebola
The evolution of Ebola virus: Insights from the 2013-2016 epidemic. (Nature paywall: $32 for a 6-page paper! Sponsored by Wellcome VIZIONS - how does that fit with Wellcome's policy in support of open and unrestricted access to research literature? You can buy a whole book on the outbreak by Constantine Nana for $7-8 - way more insights.)
Pub: Nature, October 2016.
The 2013–2016 Ebola virus disease (EVD) epidemic in West Africa appears to have begun following human contact with an animal (probably bat) reservoir of Ebola virus (EBOV) in December 2013, in the small village of Meliandou in Guéckédou Prefecture, Guinea.
Straight off the bat, the authors promulgate/imprint an unsubstantiated origin narrative, citing a paper by Baize et al - the toddler, the hollow tree, the remote village of Meliandou, Guniea - it's the pangolin narrative of the day. It sounds nice - deadly pathogens lurking in the forests of deepest, darkest Africa - fits the bill of what the public will believe. But is it true? For a start, the strain of Ebola that sparked the outbreak was related to a strain from Zaire (97%). Zaire (now Democratic Republic of Congo) is over 4000km away from Guinea. How on earth did it travel so far without infecting anyone along the way?
Oddly, for a paper titled The evolution of the Ebola virus: Insights ..., the authors skip right over any examination of this questionable foundation premise in the first sentences saying: the origin and spread of the 2013–2016 EVD epidemic seem well resolved.
In fact, Baize's paper reports the first confirmed case was in a Health worker at Gueckedou hospital, Guinea on Feb 23. It speculates about a chain of 12 unconfirmed but suspected cases, going back 83 days, to the bat tree on Dec 2 - that may have lead to the first confirmed case but notes the epidemiologic links are not well established. Including how the health worker (who spread it to several others and who represents the take-off case) contracted the disease.
That's academic skulduggery by Holmes et al. The very paper they cite to say it's well resolved says it's not well established.
Baize's not well established theory, in turn, is based on what he calls initial epidemiologic investigation that he doesn't cite but it appears to be a Fabian Leendertz expedition.
Science: Soon after the outbreak was identified as Ebola in March 2014, wildlife epidemiologist Fabian Leendertz of the Robert Koch Institute in Berlin went to southeastern Guinea to look for signs of an outbreak in wildlife. Leendertz, with three more German veterinarians spent 4 weeks in the region, capturing bats from four sites and surveying two protected forest areas.
So more than 3 months after the death of the toddler.
The researchers found no evidence that wild animals were dying of Ebola, they report in a paper published online today in EMBO Molecular Medicine. The populations of chimpanzees, duikers, and other large mammals were at about the same levels they had been in the previous surveys in the region. They also found no direct evidence of Ebola virus infections in any of the 169 bats (from at least 13 species) that they captured and tested.
No evidence of any animal infection. No evidence of bats hosting the disease. Not that that's ever stopped a zoonotic scientist before.
But their visit to Meliandou yielded intriguing clues.
(The) researchers learned of (a) tree and linked it to one of the outbreak's first victims. But, in a frustrating twist, the tree had burned to a stump just before they arrived, thwarting their search for evidence that might confirm the scenario.
So convenient. Note: when Science says the outbreak's first victims, they mean suspected. No-one from the village was definitively confirmed - they were all long dead and buried by the time Leendertz got there. Yes, they reportedly had symptoms of fever and diarrhea, but a lot of illnesses in Africa have those symptoms, including cholera.
The hollow tree was only 50 meters from the house where the toddler lived; children used to play in it, residents told the researchers. But on 24 March, the tree had burned, Leendertz says—and all that was left were the stump, fallen branches, and ashes. (It's not clear whether someone set it on fire deliberately because of the Ebola outbreak. "There are different stories about why it burned,"Leendertz says.)
Science declines to report what those stories were.
When the tree started burning, there was a "rain of bats," villagers told Leendertz—a small, smelly species with a long tail locally called lolibelo and sometimes "mice that can fly." In the ash surrounding the tree, the researchers found DNA fragments that match the Angolan free-tailed bat Mops condylurus, an insect-eating species .. that fits the villagers' description.
A hollow-tree with a lot of bats roosting in it. Not unusual. The theory was that the toddler was playing in the hollow tree and got infected. But:
... they found no infected bats in their samples (from fragments of dead ones collected around the tree).
Leendertz: The virus must be extremely rare in bat populations,. Because bats are hunted so much, if the Ebola virus were widespread, we'd see infections all the time.
This suggests that of all the bats in the tree, indeed the entire area, only one was carrying Ebola, which by chance, was the one the toddler came into contact with. That means a lone bat from Zaire somehow flew 1000's of kms to a hollow tree in the village - evolved the 3% needed to make it an identical match - then infected the toddler.
The permutations and combinations are starting to mount. As with RatG13 or the Laos bats - or the SARS-1 bat identified by Shi and Daszak - also close to 97% similarity - some astonishing evolutionary leaps must have taken place in a minuscule timeframe in order for them to infect a person 1000's of km from their origin - and no-one else in between.
Or: the Zaire strain was held at a lab in the vicinity, and the changes were done there.
To summarize, 12 unconfirmed cases along a not well established epidemiological trail, is a burned out tree that thwarted the search for evidence - with no other evidence of animal infection. In this tree, a single bat supposedly spawned a version of a 40 year-old virus from 1000's of km away then infected a toddler in a remote village - and no-one else.
Peter Walsh, Cambridge, Ebola specialist: It (the hollow tree) is suggestive, but it certainly doesn't rise to a 'smoking gun' level.
So why on earth are Andersen, Holmes, Rambaut saying the origin seems well resolved?
Thanks to this cohort of scientists, the narrative became well established - repeated by other researchers - who fed it to the media. Who printed it as science gospel. Notice any similarities? Whereas Covid became a pandemic killing millions thus inspiring a small army of internet sleuths to re-examine the official narrative, the Ebola outbreak, the biggest in history, remained largely confined to three African countries. Ebola's equally dubious origin story consequently went mostly unchallenged. Not to say there weren't researchers questioning it, Nana's research is based on several who did raise problems, but they were small enough to be brushed aside by the powerful science community elites.
And so it went that yet another dubious origin story gets passed into science zoonosis lore - without any substantial proof.