> It's possible that it's very difficult to engineer a virus that can do better than anything nature has come up with As someone finishing a PhD in computer-ai

> It's possible that it's very difficult to engineer a virus that can do better than anything nature has come up with As someone finishing a PhD in computer-aided drug discovery, this seems to be the situation in a lot of cases. Nature often finds it trivial to get around drugs and back to the viral behavior it wants. For example, a lab might make an allosteric drug that reduces the activity of a viral enzyme. In response to treatment with the drug, a few copies of the virus emerge with point mutation that makes them more active. Now a patient has two populations of viruses, and the disease no longer cares about the treatment. The surprising thing isn't just that this happens, but that it happens so rapidly, often requiring just a few days or a single mutation. A quick example of the above is the I585T substitution in [1] One big-picture concept is that genes and proteins are more than their immediate sequences/transcripts. On top of their current identity, they all exist on an mutational "landscape". Remember that some codons are redundant, while some amino acid changes would require two or three base mutations. Therefore, the sequence of a virus encodes both its current identity, as well as nearby evolutionary "alternatives". When a recurring threat comes by, the virus might have encoded in its genes a common defense, maybe through a particularly mutagen-exposed gene location or something like that. In the above case, the virus may have had millenia of exposure to weird dietary natural products and whatnot, and encoded easy rate up/down mutations for its essential enzymes, or orthosteric disruptor mutations for its promiscuous binding sites. This sort of fuckery will have to become a consideration in designing the antivirals of the future. And, to toot my own horn: In an evolutionary sense, our fight against viruses is particularly interesting. Now that computers are helping us accelerate drug development, our brains and computers could be considered as part of our immune systems. In the same way that metal weapons made us safe against macroscopic threats (lions etc), computers and public health infrastructure will become our arsenal against microscopic threats. If computer-aided drug design can lead to faster approval of cheap drugs, we can design hundreds of antiviral molecules and chase a virus all over its evolutionary landscape, until it has nowhere left to run. For out-of-field readers -- An anecdote of cancer cells (not viruses) becoming reliant on a drug in [2] [1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC296079/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC296079/ [2] http://blogs.discovermagazine.com/d-brief/2017/10/04/cancer-cells-drugs/#.WjrFFtsVhBc http://blogs.discovermagazine.com/d-brief/2017/10/04/cancer-...