Will there ever be cure for Covid or the flu?

[nec209]

I'm wondering if there will ever be anti-viral drug or treatment for Covid or the flu? I hear one  of the problems with Covid or the flu is it keeps changing all the time so I don’t know if a anti-viral drug or treatment would work with different variants.

 

 

[iNow]

Maybe but probably not

[swansont]

There is an antiviral treatment for COVID. nirmatrelvir and ritonavir, marketed as Paxlovid.

[nec209]

12 minutes ago, swansont said:

There is an antiviral treatment for COVID. nirmatrelvir and ritonavir, marketed as Paxlovid.

I believe it is use for treatment of mild-to-moderate COVID but I hear there some controversy of the drug.

[swansont]

18 minutes ago, nec209 said:

I believe it is use for treatment of mild-to-moderate COVID but I hear there some controversy of the drug.

Nevertheless, it exists. 

[CharonY]

I think when it comes to infections, it is generally more accurate to refer to treatment, rather than curing. Generally speaking, treatments aim to reduce viral load and/or supplement the ability of the immune system to do so. Antibody-based treatments can be vulnerable to mutations, but not necessarily so. Paxlovid contains an inhibitor for a viral protein, which reduces the ability of the virus to replicate. Mutations in the gene encoding that protein could reduce effectiveness, but it is still very effective in preventing death.

It is important to note that treatments are not binary. They aim to reduce viral production and accelerate clearance. Depending on when you start taking the medication has therefore a big impact on what is happening to your body. Short incubation periods (which suggests high levels of replication of the pathogen) can make things difficult, for example. Which is why vaccinations are so effective, as they basically prime your immune system to do the same thing as a treatment would. The main limitation is that the fast response (via neutralizing antibodies) drops over time, but the secondary (i.e. memory-based) response still kicks in.

So basically the best "cure" as in not getting (seriously) sick is still being up to date with vaccinations.

 

 

[Sensei]

6 hours ago, nec209 said:

I'm wondering if there will ever be anti-viral drug or treatment for Covid or the flu? I hear one  of the problems with Covid or the flu is it keeps changing all the time so I don’t know if a anti-viral drug or treatment would work with different variants.

I think it's worth noting that this is not about COVID-19 and flu, but about RNA viruses vs DNA viruses.

https://www.google.com/search?q=rna+mutations+vs+dna+mutations+viruses

"Rates of spontaneous mutation vary amply among viruses. RNA viruses mutate faster than DNA viruses, single-stranded viruses mutate faster than double-strand virus, and genome size appears to correlate negatively with mutation rate."

"RNA viruses have high mutation rates—up to a million times higher than their hosts"

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6107253/

"Their inherently high mutation rates yield offspring that differ by 1–2 mutations each from their parent [9], producing a mutant cloud of descendants that complicates our conception of a genotype’s fitness. Their ability to rapidly change their genome underlies their ability to emerge in novel hosts, escape vaccine-induced immunity, and evolve to circumvent disease resistance engineered or bred into our crops [10, 11]. On the other hand, their mutation rates are an exploitable Achilles’ heel: researchers and clinicians can increase RNA virus mutation rates using nucleoside analogues, and a 3–5-fold increase in mutation rate causes lethal mutagenesis in human-infecting viruses like poliovirus and influenza [12, 13]. The exogenous mutagen causes enough additional mutations, which are often deleterious, so that the progeny RNA viruses are of lower fitness, eventually leading to ecological collapse of the population"

[dimreepr]

14 hours ago, Sensei said:

I think it's worth noting that this is not about COVID-19 and flu, but about RNA viruses vs DNA viruses.

No it's not, as noted by @CharonY, it's about the evolution of <insert thing> and how unlikely it is that a cure, will be final...

[Agent Smith]

That's on target, but not all viruses are like that. Per my files (rather outdated), the polio virus has not undergone any significant mutation in the last 50 or so years, at least none that would affect the efficacy of the 2 vaccines that are around (one live, the other killed). I wonder why some viruses have such high degrees of genomic instability. There origins too remain a mystery, to me at least. 

[CharonY]

2 hours ago, Agent Smith said:

That's on target, but not all viruses are like that. Per my files (rather outdated), the polio virus has not undergone any significant mutation in the last 50 or so years, at least none that would affect the efficacy of the 2 vaccines that are around (one live, the other killed). I wonder why some viruses have such high degrees of genomic instability. There origins too remain a mystery, to me at least. 

The mechanisms are actually known and is largely related to their replication mechanism. RNA viruses, including poliovirus have fairly high mutation rates and SARS-CoV-2 is actually on the lower end for RNA viruses. Conversely, poliovirus is on the higher end of the scale. Conversely, poliovirus has a much smaller genome (7.5 k vs 30k). 

The reason why we have so many SARS-CoV-2 variants is likely related to yet another factor, namely the fact that so many people have been infected. For example, at the peak of polio outbreaks in the USA ca. 50k individuals were found to be infected in a year. At the peak of the SARS-CoV-2 pandemic, the USA had over 900k cases per day.  The high circulation ultimately means more mutations and higher chance of positively selectable traits. 

[Agent Smith]

10 hours ago, CharonY said:

The mechanisms are actually known and is largely related to their replication mechanism. RNA viruses, including poliovirus have fairly high mutation rates and SARS-CoV-2 is actually on the lower end for RNA viruses. Conversely, poliovirus is on the higher end of the scale. Conversely, poliovirus has a much smaller genome (7.5 k vs 30k). 

The reason why we have so many SARS-CoV-2 variants is likely related to yet another factor, namely the fact that so many people have been infected. For example, at the peak of polio outbreaks in the USA ca. 50k individuals were found to be infected in a year. At the peak of the SARS-CoV-2 pandemic, the USA had over 900k cases per day.  The high circulation ultimately means more mutations and higher chance of positively selectable traits. 

Perhaps due to their usual function/purpose, RNA is more unstable than DNA. 🙂

Edited February 2 by Agent Smith

[CharonY]

1 hour ago, Agent Smith said:

Perhaps due to their usual function/purpose, RNA is more unstable than DNA. 🙂

It is not so much the inherent stability of the molecule that causes mutations, but rather the difference in copying the genetic material (which is more prone to errors in RNA viruses for a variety of reasons).

[Agent Smith]

2 hours ago, CharonY said:

It is not so much the inherent stability of the molecule that causes mutations, but rather the difference in copying the genetic material (which is more prone to errors in RNA viruses for a variety of reasons).

Si, that's correct. Could one reason be that RNA isn't protected by complementary strand pairing like DNA? ssRNA I know exists, but dsRNA, my files return null.

[CharonY]

8 hours ago, Agent Smith said:

Si, that's correct. Could one reason be that RNA isn't protected by complementary strand pairing like DNA? ssRNA I know exists, but dsRNA, my files return null.

There dsRNA viruses (e.g. rotavirus), and are obviously also formed during replication. One important regulator of mutation rates are proof-reading mechanisms that recognize and remove mismatches during replication. Many RNA viruses don't have them (but SARS-Cov-2 does, which is why its mutation rate is a bit lower). Other factors are replication speed. Some polymerases work very fast which allows for imperfect matches to go through.