5 ms·

One thing that worries me is if we 'exterminate the common cold' will we then preferentially encourage the evolution of something worse? e.g. if the existing Rh

One thing that worries me is if we 'exterminate the common cold' will we then preferentially encourage the evolution of something worse? e.g. if the existing Rhinoviruses are somewhat symbiotic, that is, they cause sickness in the host to spread themselves, but they are an annoyance, not life threatening in most cases. Now if we have a vaccine for those, do those relatively benign viruses evolve to bypass the vaccine, but in doing so pick up more dangerous mutations in that process?

donkarma 5y ago
One worry is that if a vaccine allows for transmission but doesn't generate anything when it comes to effects from the virus, it'll let the virus evolve more dangerous mutations without becoming an issue. This could be potentially dangerous to people who are unvaccinated or if it manages to get past the vaccine. I'm probably pretty in favor of keeping the common cold as it's never killed anyone and helps train the immune system
- deleted 5y ago
  [deleted]
- lamontcg 5y ago
  > One worry is that if a vaccine allows for transmission but doesn't generate anything when it comes to effects from the virus That isn't a real worry, that is a science-fiction worry. Viral load, transmissibility and virulence are fairly tightly coupled and they will definitely not come fully uncoupled like that.
  - fao_ 5y ago
    At the risk of sounding like someone who is posited against the vaccine (I'm not, and I'm looking to receiving my second dose soon), where is your citation on this?
    - lamontcg 5y ago
      > By far, the most widely studied trade-off involves transmission and virulence (Anderson and May, 1982; Frank, 1996; Alizon et al. 2009). Transmission and virulence are linked by within-host replication: increasing parasite abundance increases the likelihood of transmission, but also increases the likelihood of host death; mathematically, this assumption can be formalized by making transmission rate β an increasing function of parasite-induced mortality rate ν. Nearly all of the literature we summarize below assumes this trade-off. https://www.cambridge.org/core/journals/parasitology/article/adaptive-evolution-of-virulence-a-review-of-theoretical-predictions-and-empirical-tests/30EC8AB1717BF7A173CF5E051DBB498F https://www.cambridge.org/core/journals/parasitology/article... Anderson, R. M. and May, R. M. (1982). Coevolution of hosts and parasites. Parasitology 85(Pt 2), 411–426. Frank, S. A. (1996). Models of parasite virulence. Quarterly Review of Biology 71, 37–78. Alizon, S., Hurford, A., Mideo, N. and Van Baalen, M. (2009). Virulence evolution and the trade-off hypothesis: history, current state of affairs and the future. Journal of Evolutionary Biology 22, 245–259.
    - zwaps 5y ago
      Data from Israel suggests that the vaccine reduces transmissivity by 70 or so per cent. I do not have the link handy, but there is definitely a coupling. It's not 100%, but it seems to be more than we hoped for. At least for covid, the viral load is reduced and infection depends on that.
chiefalchemist 5y ago
Flip it around as well. Take for example Zika. When passed from mother to unborn it can cause various brain abnormalities. But perhaps eons ago a virus is what made homo sapiens more intelligent. If a virus can mangle the brain it can also nudge it in a positive direction. Finally, human DNA is peppered with traces of viruses. https://www.smithsonianmag.com/science-nature/virus-genes-human-dna-may-surprisingly-help-us-fight-infections-180958276/ https://www.smithsonianmag.com/science-nature/virus-genes-hu...
- xvilka 5y ago
  Not only peppered, it's the main dish: 8% is direct viral remains, while other 40% have a viral origin.
nanagojo 5y ago
Don't think it works like that. Nothing is stopping other viruses from infecting you while you are infected.
- xvilka 5y ago
  Actually it is: https://www.statnews.com/2021/01/31/a-viral-mystery-can-one-infection-prevent-another/ https://www.statnews.com/2021/01/31/a-viral-mystery-can-one-...
fwip 5y ago
Viruses (or bacteria) don't "evolve to bypass" vaccines, antibiotics, or anything else. They generally have a pretty constant mutation rate, the vast majority of which are deleterious. The more people that have a virus, the more copies are out there mutating, and the more mutations (in total) you'll see. If you introduce negative pressure, like a vaccine or antibiotics, some of those mutations that were previously deleterious will turn out to be a net benefit. E.g: A thicker cell wall in bacteria makes it harder to absorb nutrients, but also increases the dose of antibiotic it can survive. These mutations happen all the time by chance, but in the absence of the vaccine/antibiotics, they are less fit and will tend to die off. A vaccine that eliminates a virus is likely to result in less infections. Less infections means less mutations means less chance for a dangerous variant. If some variants do evolve that escape the vaccine, odds are good that they will be less dangerous than the original, not more.
- jimmydorry 5y ago
  This notion appears to go against all the expert advice against (ab)using anti-biotics. Sure, less infections means less chance for mutations, but due to the fundamental forces at play, the resistant mutations will spread faster through the resistant population and eventually become the prevalent strain. Unless you can eradicate the virus or bacteria completely (mass effective vacination), the tools we create to fight them are really only delaying the inevitable. >If some variants do evolve that escape the vaccine, odds are good that they will be less dangerous than the original, not more. From my understanding, this is not the case. It's pure chance whether a mutation is advantageous or disadvantageous. If you are looking on a per-mutation basis, then sure, it's likely the mutation is disadvantageous. But at a population level, it's likely that atleast one advantageous mutation will emerge reasonably quickly when we are talking about something at the scale of several thousands of infections.
  - instakill 5y ago
    No. Just no. Antibiotics do not treat viruses. They treat bacterial infections, which WILL mutate and evolve as you claim with overuse of antibiotics. This does not apply in the slightest to VIRAL infections.

donkarma 5y ago

One worry is that if a vaccine allows for transmission but doesn't generate anything when it comes to effects from the virus, it'll let the virus evolve more dangerous mutations without becoming an issue. This could be potentially dangerous to people who are unvaccinated or if it manages to get past the vaccine. I'm probably pretty in favor of keeping the common cold as it's never killed anyone and helps train the immune system

deleted 5y ago
[deleted]
lamontcg 5y ago
> One worry is that if a vaccine allows for transmission but doesn't generate anything when it comes to effects from the virus That isn't a real worry, that is a science-fiction worry. Viral load, transmissibility and virulence are fairly tightly coupled and they will definitely not come fully uncoupled like that.
- fao_ 5y ago
  At the risk of sounding like someone who is posited against the vaccine (I'm not, and I'm looking to receiving my second dose soon), where is your citation on this?
  - lamontcg 5y ago
    > By far, the most widely studied trade-off involves transmission and virulence (Anderson and May, 1982; Frank, 1996; Alizon et al. 2009). Transmission and virulence are linked by within-host replication: increasing parasite abundance increases the likelihood of transmission, but also increases the likelihood of host death; mathematically, this assumption can be formalized by making transmission rate β an increasing function of parasite-induced mortality rate ν. Nearly all of the literature we summarize below assumes this trade-off. https://www.cambridge.org/core/journals/parasitology/article/adaptive-evolution-of-virulence-a-review-of-theoretical-predictions-and-empirical-tests/30EC8AB1717BF7A173CF5E051DBB498F https://www.cambridge.org/core/journals/parasitology/article... Anderson, R. M. and May, R. M. (1982). Coevolution of hosts and parasites. Parasitology 85(Pt 2), 411–426. Frank, S. A. (1996). Models of parasite virulence. Quarterly Review of Biology 71, 37–78. Alizon, S., Hurford, A., Mideo, N. and Van Baalen, M. (2009). Virulence evolution and the trade-off hypothesis: history, current state of affairs and the future. Journal of Evolutionary Biology 22, 245–259.
  - zwaps 5y ago
    Data from Israel suggests that the vaccine reduces transmissivity by 70 or so per cent. I do not have the link handy, but there is definitely a coupling. It's not 100%, but it seems to be more than we hoped for. At least for covid, the viral load is reduced and infection depends on that.

chiefalchemist 5y ago

Flip it around as well. Take for example Zika. When passed from mother to unborn it can cause various brain abnormalities. But perhaps eons ago a virus is what made homo sapiens more intelligent. If a virus can mangle the brain it can also nudge it in a positive direction. Finally, human DNA is peppered with traces of viruses. https://www.smithsonianmag.com/science-nature/virus-genes-human-dna-may-surprisingly-help-us-fight-infections-180958276/ https://www.smithsonianmag.com/science-nature/virus-genes-hu...

xvilka 5y ago
Not only peppered, it's the main dish: 8% is direct viral remains, while other 40% have a viral origin.

nanagojo 5y ago

Don't think it works like that. Nothing is stopping other viruses from infecting you while you are infected.

xvilka 5y ago
Actually it is: https://www.statnews.com/2021/01/31/a-viral-mystery-can-one-infection-prevent-another/ https://www.statnews.com/2021/01/31/a-viral-mystery-can-one-...

fwip 5y ago

Viruses (or bacteria) don't "evolve to bypass" vaccines, antibiotics, or anything else. They generally have a pretty constant mutation rate, the vast majority of which are deleterious. The more people that have a virus, the more copies are out there mutating, and the more mutations (in total) you'll see. If you introduce negative pressure, like a vaccine or antibiotics, some of those mutations that were previously deleterious will turn out to be a net benefit. E.g: A thicker cell wall in bacteria makes it harder to absorb nutrients, but also increases the dose of antibiotic it can survive. These mutations happen all the time by chance, but in the absence of the vaccine/antibiotics, they are less fit and will tend to die off. A vaccine that eliminates a virus is likely to result in less infections. Less infections means less mutations means less chance for a dangerous variant. If some variants do evolve that escape the vaccine, odds are good that they will be less dangerous than the original, not more.

jimmydorry 5y ago
This notion appears to go against all the expert advice against (ab)using anti-biotics. Sure, less infections means less chance for mutations, but due to the fundamental forces at play, the resistant mutations will spread faster through the resistant population and eventually become the prevalent strain. Unless you can eradicate the virus or bacteria completely (mass effective vacination), the tools we create to fight them are really only delaying the inevitable. >If some variants do evolve that escape the vaccine, odds are good that they will be less dangerous than the original, not more. From my understanding, this is not the case. It's pure chance whether a mutation is advantageous or disadvantageous. If you are looking on a per-mutation basis, then sure, it's likely the mutation is disadvantageous. But at a population level, it's likely that atleast one advantageous mutation will emerge reasonably quickly when we are talking about something at the scale of several thousands of infections.
- instakill 5y ago
  No. Just no. Antibiotics do not treat viruses. They treat bacterial infections, which WILL mutate and evolve as you claim with overuse of antibiotics. This does not apply in the slightest to VIRAL infections.