An article published in US News & World Report last week on an exciting possible therapy for Ebola virus disease contains some of the worst scientific misinformation we’ve yet come across. Worse, the author, Jeff Nesbit, links to a similar article he wrote last year for US News & World Report, disseminating the same nonsense.
Last week’s article is ostensibly about a new antibody-based therapy for Ebola virus infection developed by U.S. military scientists. This therapeutic candidate, an antibody cocktail that cured several monkeys suffering from Ebola virus disease, truly is an exciting scientific discovery. Both articles, however, go on to discuss something even more frightening than Ebola, the threat of Simian hemorrhagic fever virus (SHFV), jumping from non-human primates to people.
There are several problems with both the fearmongering premise and Nesbit’s background information. Nesbit starts his SHFV rant by discussing previous jumps of viruses from animals to humans like this:
“Deadly, virulent viruses have jumped species from nonhuman primates such as chimpanzees to the human species three times in history: the SIV virus that almost certainly led to the worldwide AIDS pandemic, the SV-40 “cancer” virus that was accidentally included in polio vaccines in the 1950s, and the deadly Ebola virus.”
This is bad, bad science writing, with some truth buried within wildly inaccurate history. It’s true that HIV is derived from simian immunodeficiency viruses, but that’s about as far as this paragraph gets without going off the rails. SV40 virus is indeed a simian virus that may have come to infect humans. We know, for example, that old polio vaccine stocks were contaminated with this virus, and that SV40 has been shown to cause cancer in small lab animals. Calling it the “cancer” virus, however, is inaccurate and inflammatory. Studies in the U.S. and Denmark, along with a larger analysis by the National Cancer Institute, have found no evidence that SV40 causes cancer in humans. Finally, we come to the easiest allegation to knock down, that Ebola virus jumped from non-human primates to people. In fact, the strongest evidence we have suggests that fruit bats are the reservoirs of Ebola and other similar viruses. It’s true that Ebola virus infects non-human primates in the wild and in captivity, but the source of any particular Ebola outbreak has never been identified, and it is decidedly not a virus harbored by primates.
It also needs to be point out that while the article rattles off two terrible examples of viruses that have crossed from animals into people, saying it’s happened three times in history is just silliness. It’s actually estimated that up to 75% of emerging diseases in humans came from animals. The list includes, aside from Nesbit’s three examples, Nipah virus, influenza viruses, rabies virus, and West Nile virus. We could go on, but won’t.
Next on the author’s agenda is convincing you that SHFV might be the next human plague:
“Because it is a close cousin to Ebola, biodefense researchers are also looking at SHFV. Both Chinese and U.S. researchers assume, for now, that it might be benign and a way to study the Ebola virus. And if it jumps to the human species — just as SIV, SV-40 and Ebola did — then the human species is nearly defenseless against it.”
From the top, SHFV actually is not a close cousin of Ebola at all. They cause a somewhat similar disease, but are virologically quite distinct. They share neither, a species, genus, family, or order. SHFV is an arterivirus, whereas Ebola is a filovirus. They have nothing in common in terms of shape or genome structure, and have drastically different replication cycles. SHFV is studied because the course of disease is similar, but it’s in fact a well-known virus, prized in the lab specifically because it does not infect humans, or human cells in the lab. There’s really no reason to consider SHFV an impending threat, and, accordingly, it’s studied in low biocontainment facilities. It’s true that we would be immunologically defenseless against SHFV were it to infect humans, but that’s true of most emerging pathogens, and not unique to this situation at all. We at PHU would never sit here and say SHFV could never infect a human, as viruses do make the species jump, as we’ve seen. But you can bet that for the virus to be studied in low containment that the risks have been evaluated, and the focus here should be on how SHFV can help us understand and treat disease in humans, not how it might make us sick itself. The article does close this way:
“And if it jumps to the human species — just as SIV, SV-40 and Ebola did — then the human species is nearly defenseless against it. But if it doesn’t — or can’t — jump from primates to us, then it just as equally could hold the key to a defense against the quite deadly Ebola virus.”
So he’s reined himself in at the end. We think it’s too late though; there didn’t need to be even a sentence suggesting you should fear SHFV. And the author certainly didn’t need to lump SV40 in with SIV and Ebola again, considering it’s never made someone sick. This is just the kind of article that makes us bang our heads on our desks, so we decided to make ourselves feel better by making sure you don’t believe more than a word or two of it. If you do want to learn more about the new Ebola therapy US News ostensibly reported on, here’s a much better article from NBC. It’s actually quite cool. The actual article in Science Translational Medicine can be found here.