[Pixie (OP)]

Hi! I'm new to the forum so I'll start with a quick intro. I'm Paula, I'm 25 and I'm from Glasgow, Scotland. My partner and I have two kids. He is a chef and I'm a writer.

Anyway- to the viruses.

I'm doing some research for my next piece and need to ask about viruses harboured by rivers or on riverbeds. Which are the most deadly and how do they mutate?

Please forgive me if I ask a lot more ridiculous and random questions. It helps me in my field to try to know what I'm talking about so a story seems more viable! Also, I'm generally quite a curious person anyway. Thanks!

[blakestyger]

I've just Googled viruses in rivers - having an interest in the things myself - and there's loads of stuff.

(This probably isn't in the true spirit of TNS, but Dexter is about to start). []

[RD]

Anyway- to the viruses.

I'm doing some research for my next piece and need to ask about viruses harboured by rivers or on riverbeds.
 Which are the most deadly and how do they mutate?
 

New viruses can be created when a host is simultaneously infected by two different viruses ...

 [ Invalid Attachment ]

Here's a topical virus-in-water idea: ancient virus, (pathogenic to humans), trapped in Arctic ice for millennia, released into oceans by global warming (melting ice).

Bugger, its been done ... http://www.independent.co.uk/news/science/global-warming-death-in-the-deepfreeze-508727.html


[BTW don't confuse viruses with bacteria ... http://www.foodsafety.gov/~dms/qa-fdb38.html]

[Pixie (OP)]

Anyway- to the viruses.

I'm doing some research for my next piece and need to ask about viruses harboured by rivers or on riverbeds.
 Which are the most deadly and how do they mutate?
 

New viruses can be created when a host is simultaneously infected by two different viruses ...

 [ Invalid Attachment ]

Here's a topical virus-in-water idea: ancient virus, (pathogenic to humans), trapped in Arctic ice for millennia, released into oceans by global warming (melting ice).

Bugger, its been done ... newbielink:http://www.independent.co.uk/news/science/global-warming-death-in-the-deepfreeze-508727.html [nonactive]


[BTW don't confuse viruses with bacteria ... newbielink:http://www.foodsafety.gov/~dms/qa-fdb38.html [nonactive]]

Oooh! That is interesting! Can any viruses mingle together or do they have to be of the same "type" (eg: Can the flu and hepititus create somethig all-together different?)

I vaguely remember something from Biology about RNA receptors and how viruses invade cells but nothing about them minglig. That's a special lil twist indeed!

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[RD]

Dr Chris Smith, (the founder of this site), is the person to ask about viruses ...

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http://www.thenakedscientists.com/forum/index.php?action=profile;u=9



I believe that combination is more likely if the viruses are of similar type ... http://www.euro.who.int/influenza/20080618_7

[Variola]

Oooh! That is interesting! Can any viruses mingle together or do they have to be of the same "type" (eg: Can the flu and hepititus create somethig all-together different?)

I vaguely remember something from Biology about RNA receptors and how viruses invade cells but nothing about them minglig. That's a special lil twist indeed!

As I understand it, the virus is generally one of the same family, i.e influenza being one of the most common to mutate. They need to have homologus genes, thats is genes that are similar in sequence and structure rather than analogus.
Infuenza in particular is a good shape shifter, it uses birds and pigs as 'hotel's in which to have a good old mooch about meeting other strains of influenza they can meet and have 'viral sex' with, often within a cell(s). This can change the viruses conformation and it has a whole new species it can now infect. You can almost view it like having the keys to the front and backdoor of one type of house, then meeting someone who gives you the front and back door heys to another set of houses as well, and you can go in and help yourself!!!!
Due to their biology, pigs are a great vector for tranferring usually zoological viruses over to humans and back again. And when birds, pigs and humans live in close contact with one another, you can get some inevitable virus mixing. And for purposes of your research, or writing, places like Asia often farm fish, birds and pigs in close proximity, and next to a water source like a river.
The same happens within large populations of the world, again to use influenza as an example, people tend to sneeze a lot when they have 'flu, which is by far the best transport mode for a virus to vacate the hosts body and get inhaled straight into the lungs of another. With the advent of travel and particulary air travel, its made it much easier to spread viruses within the world population. ( Antigenic shift)
Other than that, most viruses don't mutate that often, the exception being influenza and HIV virus. However because viruses do have a high replication rate, there is also a higher rate of error in replications, causing a mutation. While the mutation does not affect the virus itself, it could be a mutation that causes it to be able to invade cells more easily, or escape detection by an immune system already vaccinated against it.

Thats just a bit of basic info to give you a base, or so you can research from there as a starting point. Do ask Chris though, as he is the chief on this, and see what google throws back.  []

[wolfekeeper]

I read somewhere that water from the (IRC) River Ganges is a treatment for dysentry. You'd think it would be terrible, but apparently there's lots of viruses that kill bacteria in there, so if you drink the water, it tends to kill off the dysentry.

[chris]

Hello Paula.

Viruses change genetically in two ways:

1) They acquire mutations (changes) to their genetic material (DNA or RNA) when they replicate (copy themselves) in an infected cell.

This is elegantly demonstrated by the 'flu, which is continuously acquiring subtle genetic changes as it passes from one person to the next. This is known as antigenic drift and is the reason why you can catch it more than once and why the vaccine needs updating one year to the next.

2) Viruses can also swap genes with other viral strains, although (as a rule) not between different viruses; that said, genes can be moved from one virus to another, or even a non-virus into a virus, by scientists using genetic techniques.

In the case of the flu this is known as antigenic shift and is the source of pandemic viral strains. The hypothesis is that an animal such as a pig, which is susceptible to infection by both bird and human strains of flu, becomes co-infected with the two strains which then produce hybrid viruses containing elements of both viruses. The result can be a virus with the surface (antigenic) appearance of a bird virus but the inner workings (and hence immune-evasion and replicating strategy) of a human virus. As people have no immunity to it it sweeps through the population producing very high disease burdens.

Chris

[Variola]

^^^^^^^^

Hey looks like I was actually right in what I said!  []My fascination for immunology is paying off...!!  []

[wolfekeeper]

In Haiti in 2000, the live oral polio vaccination virus apparently got crossed with natural enteroviruses and became pathogenic again, and some children died.

So it does happen, but presumably the further apart genetically the viruses are, the less likely it is to happen. Polio is an enterovirus, so that's why it could do that, but it's pretty rare, and there's ways to vaccinate that avoid this problem.