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Comment by Medicalidiot | Hacker News Reader

I want to know how long it will take for Ebola to evolve a resistance to this therapy.

> I want to know how long it will take for Ebola to evolve a resistance to this therapy.

Maybe never. A lot of time in any case, probably. Ebola is a plant's virus adapted to trees. Evolved to use bats (and probably arboreal snakes also) but can't survive for a long time in primates, and can't survive in soil at long term. We are a dead end for it. Would need infected humans munching some inedible leaves of a tropical tree or visiting hollow trunks where bats live.

News cases of Ebola in the future will be from a new strain, but this does not imply evolution or resistance. Is just that the number of ebola specimens in contact with humans is limited.

In practical terms, there will be a resistance that develops eventually. Even though the reservoir is hypothesized to be bats, that doesn't have much significance because of its ability spread from person to person without a vector.

What is notable about Ebola is that its virulence keeps dropping while its ability to spread has significantly increased. The larger issue is that Ebola is in areas that don't have the resources to handle any serious outbreak. It's becoming more likely that Ebola is going to be self sustaining soon.

I'm kind of amazed that a comment expressing interest in when this therapy will be obsolete, see that 96% of bacteria are resistant to Penicillin G now, gets a negative response. Drugs are only effective when the pathogen is still sensitive to them.

For a resistance to develop, ebola that has been exposed to the treatment inside a hospital has to escape back into the wild. There are significant barriers in the way of that.

If everyone on penicillin was kept in an isolation chamber, the effectiveness over time would be different.

As someone who works in a hospital, we can bleach every single patient room, wear all the PPE we want, but pathogens will always spread; the only question is when, not if. Even in an isolation chamber a resistance to penicillin would develop independently of each other as penicillin resistance is usually predicated on a mutation in the penicillin binding protein.

Nothing's perfect, but ebola levels of paranoia drastically slow down any chance of spread.

While partial resistance can be encouraged in a single person, that doesn't matter if it dies inside them. And if a resistance mutation happens in the wild, away from drugs, there's no reason to expect it to spread at all.

There's a significant amount of fake news around the Ebola outbreak epicenters, such as aid workers trying to take people's blood and other conspiracy theories. We have to keep in mind some of these places recently had a genocide and/or are generally unstable.

> Ebola is a plant's virus adapted to trees.

I never heard that and I can't find that in Wikipedia. Do you have a link with more information about that?

Is a plausible hypothesis. As we all know viruses do not fosilize easily, the origin of the virus is unknown (apart that is linked with tropical forest canopies in Africa). But there are several traits that would suggest a plant patogen that jump later to animals, maybe via plant sucking arthropods, and stablish later in bigger animals eating this arthropods. I could be wrong, I don't remember when I read it, but I remember that the idea triggered a click, and makes a lot of sense to me. I'm not expert in viruses evolution in any case so take this with a pinch of salt.

Ebolavirus is a genus comprising at least five species that can create similar outbreaks. I don't know if the treatment protects from all of them (Probably not). Is a fast mutating kind of creatures also. I guess that each future outbreak will need to rebuild an specifical treatment. The good news is that we know how to rebuild it fast, there is a new awareness of the problem, and african people are fixing some cultural traditions that helped to spread the virus in the past.

There are also other two genuses closely relative to Ebolavirus: Marburgvirus (produces a similar haemorrhagic fever in humans), and the spanish surprise Lloviu cuevavirus (poorly known but assumed harmless). Treatment designed for Ebola probably will not protect from Marburg disease, but I'm speculating.

If you ever find a source for the virus for plant origin, I'd like to read it. (I'm not a biologist, but I'm curious. For example, I know about the relation with the Marburg disease.)

This therapy is intended for use in an intensive care environment. If the patient is able to pass on their infection in that environment, something is very wrong.

Treating Ebola patients in intensive care environments without a single breach in containment protocol is astonishingly difficult, even for trained and experienced teams.

Its an RNA virus, so like flu it evolves all the time. RNA viruses replicate because there is no check on the NA helix when a cell replicates, unlike DNA which by virtue of being a double helix, a basic checksum method to ensure consistency of the DNA helix which the adaptive immune system relies on to do its job.

It is why flu vaccines can be ineffective by the end of the flu season. It takes about 2 weeks to grow a flu virus in sterile eggs, the most "high tech" solution known to man currently. Every time someone with flu sneezes, they are emitting new multiple strains of the flu virus.

The other problem with Ebola is it can hide in parts of the body where the adaptive immune system does not work, places like the eye and testes. So even though the virus may not show up in test results, it could reappear when someone's immune system is weakened sometime in the future. There are other ways to kill it though. Just for reference, someone I know works at Porton Down in the UK, MOD facility, they told me Ebola is nothing compared to some of the viruses and bacteria they have in their facilities. In other words there are far worse things to be worried about than Ebola.

Viruses tend to evolve pretty quickly. In fact, Ebola's already not just one strain, so differing Ebola strains are likely more prone to different versions of this treatment.

In practice, it'll probably work out to be sorta like the issue with flu vaccinations, where health organizations will have to predict which strains are likely to be out there and then prepare accordingly.

Still, even if Ebola somehow rapidly evolved to completely ward off the current treatments, it's moreso the technology that created these treatments that's a breakthrough. So, if Ebola adapts, presumably they'd just update the treatments.

That said, the current treatments probably aren't very optimized yet, either. These are early successes; future results seem liable to be much better.

How you would know that? You only could know after it happened. Evolution is random.

Well, going out on a limb here, there should still be some way to give a statistical apprehension of how likely such mutation could be over time. But I'm not aware if there's any feasibility of doing that today.

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