That's what testing is for, of course. If you take a look at for example figure 6B in the paper (link)
, you can see that the cells clearly suffer no problems due to the DRACO. It has already been tested in mice, actually, as shown in figure 9 and in the text, so in vivo applications seem to work well.
I read the paper, but it seems they have only tested it on 11 mammalian cell types. There are about 210 distinct types of cell in the human body alone, and they have only carried out in-vitro human tests that do not replicate the normal cellular environment. It is a promising study, and I know these things take time, but they have a lot more testing to do in order to convince me of the safety and viability of this treatment.
Especially considering that the vast majority of viral illnesses are self-limiting, completely resolving over a number of days with non-antiviral care alone. So weighing the risks and the benefits, unless this treatment is definitively proven 100% safe (unlikely), it could not be recommended over non-treatment no matter how high the efficacy.
Are you sure there is a lot of host/resource competition in viri? I think their main opponent would be the immunesystem, which means resource competition doesn't come into play. I may be wrong about this though.
Evolution itself can only occur in the face of a resource-struggle. This is a universal principle, and is a pre-requisite for natural selection. So any form of life on the planet competes for resources in some shape or form, or else it would not exist. A virus would find it difficult to infect a host, for example, if the host's immune system is already at 100% due to the presence of a pre-existing infectious disease.
I don't believe your dam analogy is accurate. This would be more accurate: We build a dam against most current viri, by preventing long dsRNA to be present. Then, because of mutation, there might come a virus with a method of replication that doesn't use long dsRNA, which can be represented by water not blocked by the dam. A spill-over, if you like. This doesn't mean however, that the dam is cracking; i.e., it doesn't mean that suddenly all viri have this dsRNA-less reproduction.
Of course, the new viri can still be countered the normal way; by specific binding to virus types.
This is not correct. If there is a massive selection pressure put on the virus population, such as DRACO, any mutations that are advantageous can be transmitted very rapidly by horizontal gene transfer
. I.e. transmission of genes from an organism without being a direct offspring of the organism itself. This can rarely occur in more complex organisms, but it a typical trait of viruses. Also, because of natural selection, any virus that doesn't have the mutation will (by definition) be killed by the selection pressure, leaving only the mutated successful viruses alive. All of this can result in periods of hyper-evolution following a significant stressor.
However, this is not really what I meant with the analogy. Consider the damn to be an antibiotic, and the water to be a particular microbe. If the antibiotic suddenly becomes ineffective at treating the infection, then the damn has been effectively breeched as there is no effective treatment other than that single antibiotic. I know we have multiple antibiotics available, but this essentially translates to a crack in the damn being patched over, which will eventually fail in the same way until the entire structure can no longer cope. Unless we start to use our antibiotics more carefully, I can guarantee you that we could all be suddenly (i.e over the space of a few years) drowned in microbes that we have no effective treatments for.
The analogy though is admittedly not perfect, but I just wanted to illustrate my point about the anti-microbial arms race, and how microbes are much more effective at evolving than we are at innovating. It may not seem like it, but when you have a patient who has a methicillin-resistent Staphylococcus Aureus infection and you have no working antibiotics to treat them with, the reality of the damn-bursting becomes much more striking.
At the very least it creates a unique solutions for "difficult diseases". Things like ebola, but also strains of influenza we don't have any anti-virals against. Using it en-masse, is an interesting option, which should be considered very carefully, if it is possible.
I do see the potential of a therapy like DRACO, it might even be able to cure HIV! But If we use it over-judiciously I would be extremely worried about the kind of viruses that might emerge after the inevitable occurs and they eventually evolve a defense for DRACO. It could leave them completely impervious to our own host-defences (as they work essentially the same way), leaving our immune systems totally useless without technological assistance and further innovation in the future.
The more we try to kill viruses and bacteria, the more dangerous and virulent they become. This is a fact, and we have no hope of eradicating them completely. And even if we managed to do that, we would be signing the death certificate of every other organism on the planet, because future evolution and horizontal gene transfer would no longer be able to occur.
Instead of coming up with new methods of destroying viruses, we need to accept them as something that is necessary and natural, and only treat infectious diseases which would likely kill the patient if left untreated. Very few viruses fall in this category.