4 ms·

It would seem to me that this concept of the strongest strain taking over only would happen if there were some sort of competition for resources. If you have on

It would seem to me that this concept of the strongest strain taking over only would happen if there were some sort of competition for resources. If you have one strain of HIV it seems weird to think that it would stop you from getting another strain and then passing both on. But "not my area of expertise" either.

nonbel 10y ago
First, it seems very difficult (for a virus) to transmit HIV via vaginal intercourse[1]. Second, most infections appear to start from a single virus,[2] despite the huge genetic diversity of intrapatient HIV that supposedly makes it hard to treat[3]. That means most of the strains found within one person never get transmitted. How do you manage to transmit HIV contaminated fluids but only one infection occurs in the receiving person? Very strange. Another strange thing, it does not seem all that difficult (relatively) for interspecies transmission to occur: "Scientists have now documented that the SIV virus has jumped from monkeys or apes into humans at least 13 separate times!"[4] Perhaps those transmissions are due to self-injury while cutting infected meat, etc. The vagina is tissue that expects the presence of foreign human cells, and so has defenses against them. Anal sex, injections, etc are a different story. To me it sounds like an entire cell gets transmitted. [1] http://m.jid.oxfordjournals.org/content/191/9/1403.full http://m.jid.oxfordjournals.org/content/191/9/1403.full [2] http://www.ncbi.nlm.nih.gov/m/pubmed/18490657/ http://www.ncbi.nlm.nih.gov/m/pubmed/18490657/ [3] http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2614444/ http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2614444/ [4] http://evolution.berkeley.edu/evolibrary/news/081101_hivorigins http://evolution.berkeley.edu/evolibrary/news/081101_hivorig... EDIT: Another possibility is that the vast majority of these variants found floating free in the blood are non-functional and serve as chaff to confuse the immune system.
Fomite 10y ago
The concept is known as "vaccine escape" and is present in some viral diseases but not others. I confess I don't know how between-strain viral dynamics of HIV work, but it was definitely a concern for HPV, though it does not appear to be happening.
ufo 10y ago
Most of the different variations of HIV found inside an infected person evolved inside that person from one or two initial strains they were infected with. The various HIV strains inside the body compete with each other over infected cells. Once you kill some of the strains with a treatment it opens up space for the other strains to to fill.

nonbel 10y ago

First, it seems very difficult (for a virus) to transmit HIV via vaginal intercourse[1]. Second, most infections appear to start from a single virus,[2] despite the huge genetic diversity of intrapatient HIV that supposedly makes it hard to treat[3]. That means most of the strains found within one person never get transmitted. How do you manage to transmit HIV contaminated fluids but only one infection occurs in the receiving person? Very strange. Another strange thing, it does not seem all that difficult (relatively) for interspecies transmission to occur: "Scientists have now documented that the SIV virus has jumped from monkeys or apes into humans at least 13 separate times!"[4] Perhaps those transmissions are due to self-injury while cutting infected meat, etc. The vagina is tissue that expects the presence of foreign human cells, and so has defenses against them. Anal sex, injections, etc are a different story. To me it sounds like an entire cell gets transmitted. [1] http://m.jid.oxfordjournals.org/content/191/9/1403.full http://m.jid.oxfordjournals.org/content/191/9/1403.full [2] http://www.ncbi.nlm.nih.gov/m/pubmed/18490657/ http://www.ncbi.nlm.nih.gov/m/pubmed/18490657/ [3] http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2614444/ http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2614444/ [4] http://evolution.berkeley.edu/evolibrary/news/081101_hivorigins http://evolution.berkeley.edu/evolibrary/news/081101_hivorig... EDIT: Another possibility is that the vast majority of these variants found floating free in the blood are non-functional and serve as chaff to confuse the immune system.

Fomite 10y ago

The concept is known as "vaccine escape" and is present in some viral diseases but not others. I confess I don't know how between-strain viral dynamics of HIV work, but it was definitely a concern for HPV, though it does not appear to be happening.

ufo 10y ago

Most of the different variations of HIV found inside an infected person evolved inside that person from one or two initial strains they were infected with. The various HIV strains inside the body compete with each other over infected cells. Once you kill some of the strains with a treatment it opens up space for the other strains to to fill.