5% have 2 viruses

[gsgs]

Professor Booy said it was possible for a person to catch the seasonal flu and swine flu, which did not necessarily make for an illness twice as bad. He said one in 20 children who presented to hospitals with a virus had two viruses.

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[GaudiaRay]

Re: 5% have 2 viruses

Is it fair or within accurate to assume that this 5% dual virus number is extendable to all or most viruses in humans?

Would it be this 5% of dual virus occurance that drives homologous recombination?

I'll be ever so unscientific and say 'Yes, there "it" is.'

 

[gsgs]

Re: 5% have 2 viruses

once we have cheap quick-tests for several flu-strains, then we may
manipulate flu-evolution towards less virulent strains :
quarantine those with two "evil" viruses

well, by that time we may have eradicated (mammalean) flu entirely...

 

[HenryN]

Re: 5% have 2 viruses

Is it fair or within accurate to assume that this 5% dual virus number is extendable to all or most viruses in humans?

Would it be this 5% of dual virus occurance that drives homologous recombination?

I'll be ever so unscientific and say 'Yes, there "it" is.'

Yes, dual infections are common and are the key driver of flu evolution.

 

[nomadic wench]

Re: 5% have 2 viruses

So what are the chances that a recombinant of the two strains would be 100% resistant to Tamiflu? (Not that I'm a great believer in Tamiflu anyway)

 

[gsgs]

Re: 5% have 2 viruses

when you say 100%, then I say (close to) 0%

 

[nomadic wench]

Re: 5% have 2 viruses

50%?

What are the laws of genetics with viruses. I've only done sweet peas.

 

[AlaskaDenise]

Re: 5% have 2 viruses

.....What are the laws of genetics with viruses. ........

After reading about influenza for a few years, I (non-scientist) believe the "laws of influenza" are: Whatever works!

.

 

[gsgs]

Re: 5% have 2 viruses

you really mean : "recombine" in the sense how we use it here,
not "reassort" ?


so, assuming a recombination (which is not just reassortment, so unlikely IMO)
of M**flu+H1N1 seasonal flu , and given that a viable
and spreading new virus emerges

Then I'd estimate 30% that this virus is less than half as sensitive
to Oseltamivir as M**flu


hmm, not much different if we assume reassortment instead of recombination

however the new virus could have HA from seasonal flu or HA from M**flu
with almost the same likelyhood

 

[nomadic wench]

Re: 5% have 2 viruses

you really mean : "recombine" in the sense how we use it here,
not "reassort" ?

I think so but not 100% sure... in layman's language

When one strain meets a different strain and they have babies...that's "recombine" isn't it? I was thinking of H1N1 (novel) +H1N1 (seasonal) Like two different species mating

Reassort.... I think of that as being when two of the same strain (species) get together and have babies with blue or brown eyes.

But it could be the opposite so correct me if I'm wrong.

PS Where can one get a crash course on all this stuff.... I see your posts and the strings of numbers mean nothing to me but I'd quite like them to.

 

[wotan]

Re: 5% have 2 viruses

Barry's The Great Influenza gives a good explanation. He describes reasortment as taking two deck of cards, shuffling them together and dealing out a new 52 card deck from the results. He compared recombination to taking the cards, cutting them in half, then randomly taping them back together.

 

[nomadic wench]

Re: 5% have 2 viruses

Afterthought....can H1N1(swine) and H1N1(seasonal) actually be considered different "species"?

Both have the same name (something to do with the virus structure I think) but the former is something we've never seen before.

Thank you Wotan...I'll try and find it!

 

[wotan]

Re: 5% have 2 viruses

They are subtypes of the infleuenzavirus A species. Don't have time to pull up the link, but find the wikipedia article for influenza.

 

[gsgs]

Re: 5% have 2 viruses

flu viruses have 8 segments, with ~
(2200,2200,2100,1700,1500,1400,1100,900)
nucleotides.

2 viruses may shuffle their segments e.g. 11111111+22222222 -> 11111221
as in the case of M**flu creation where 1 was American swine and 2 was Eurasian swine
This is called reassortment.
http://en.wikipedia.org/wiki/Reassortment

Sometimes it seems to happen i.e. in swine or birds that within one segment
subsequences are mangled e.g. within segment 1

.aaaaaaaaaaaaaaaaaaaaaaaaa....(length=2200)
+bbbbbbbbbbbbbbbbbbbbbbbbb...(length=2200)
=aaaaaaaaabbbbbbbbbbbaaaaaa...(length=2200)

when a small chunk of strain b's segment 1 was inserted into strain a's
segment 1. This is (usually) called recombination.
The other segments are not affected, but may recombine or
reassort independently.
http://en.wikipedia.org/wiki/Genetic_recombination
http://en.wikipedia.org/wiki/Homologous_recombination


if some people without pre-education want to learn this a bit and how to
read mutation tables, comparison lists, phylogenetic trees,... I may
write an explanation, introduction.
You can start to read something at wikipedia, which I think is usually
a good source.
influenza
influenza-research
influenza genetics
etc.

 

[wotan]

Re: 5% have 2 viruses

In the (admittedly) simplified explanation from Barry, the cards would be the segments.

 

[gsgs]

Re: 5% have 2 viruses

you won't shuffle the segments in one virus.

take 8 piles of 2 cards : Ace,2,3,...,8 heart and clubs
then shuffle each of the 8 piles
then take the top card from each pile

 

[Skatman]

Re: 5% have 2 viruses

I think so but not 100% sure... in layman's language

When one strain meets a different strain and they have babies...that's "recombine" isn't it? I was thinking of H1N1 (novel) +H1N1 (seasonal) Like two different species mating

Reassort.... I think of that as being when two of the same strain (species) get together and have babies with blue or brown eyes.

But it could be the opposite so correct me if I'm wrong.

PS Where can one get a crash course on all this stuff.... I see your posts and the strings of numbers mean nothing to me but I'd quite like them to.

Here is a good video on recombination from HHMI.

http://www.hhmi.org/biointeractive/media/recombination-lg.mov

And a paper from HHMI on the H1 binding of the avian 1918/H1N1 to human transmission

http://www.hhmi.org/news/1918flu.html