Waterborne Viruses ?

[Lost_Patrol]

I have bought a Katadyn Hiker water filter that I'm intending to use in Scotland. It filters out cysts and bacteria (like crypospiridium and giardia) but not viruses. Due to thyroid problems I can't use filters that include an iodine stage.

My understanding of viruses is that they can't live for long outside a host. My question is - Is it necessary to boil or chlorine treat my water after filtering if I take it from clean looking countryside streams ?

I know that things like typhoid are virus based but I wouldn't expect this to be a problem in Scotland. Anyone know how real a threat virises are in Scottish streams ?

 

[Nemisis]

I would boil anyway no matter how clean a stream looked you've no idea what might be in the water upstream i.e. a dead animal etc.
Dave.

 

[PC2K]

nah... it's to cold in scotland for virusses to live out of a host. Not a real problem in europe.

 

[Toddy]

Where are you going in Scotland?
Personally I wouldn't drink from most of the central belt waters just 'cos most of us live there and there's no way of easily telling how 'clean' the water is even though it looks pristine.
Farmland run off can be awful stuff too, I had a friend who caught brucellosis (bacteria I think, so that ought not be a problem with your filtering) after canoeing and capsizing downstream from a dairy farm.
That said, I have drunk from waters all over the country and never even had the squits....watch the flak fly now I know, I know, it's not advised, but many folks do it. I think it's up to you whether or not you are prepared to risk it....."water borne pathogens, Campylobacter, Salmonella, Cryptosporidium, Giardia spp. and E.coli O157 are the most important " Seems these represent 95% of all of these infections in Scotland." but I cannot find any details of how prevalent the virus ones actually are.
Don't think I've been much help Sorry.
Cheers,
Toddy

 

[shadow57]

A virus is not really a living organism. It cannot move around .....but it can replicate itself inside a specific living cell. Outside a host cell..... its just a bit of DNA with a protein coating doing nothing.

They are very small...in one drop of water you could have 100,000 bacteria....in one bacteria you could have 100,000 viruses. cannot see these filters stopping viruses

The virus needs to be in the correct cell to replicate...a cold or flu virus needs to be in the cells lining your nose.

Boiling the water should kill most bacteria and viruses. That what I would do

Don,t trust these water filters...John

 

[Lost_Patrol]

Thanks all. I'll probably boil it after filtering to be on the safe side.

Toddy, I'm planning to canoe across lochs ba and laidon on Rannoch moor, and camping on one of the islands. I was thinking about using the streams feeding into these lochs. I've drunk the water from high in the hills around Glencoe without problem, but this would be lower down the chain and subject to more possible pollution
.

 

[Toddy]

Thanks all. I'll probably boil it after filtering to be on the safe side.

Toddy, I'm planning to canoe across lochs ba and laidon on Rannoch moor, and camping on one of the islands. I was thinking about using the streams feeding into these lochs. I've drunk the water from high in the hills around Glencoe without problem, but this would be lower down the chain and subject to more possible pollution
.

My father got rheumatic fever back in the 1930's, long recovery periods were normal but no dhss or invalidity benefits back then. His parents had three other children in apprenticeships and money was tight. He took himself off with an ex- army pup tent, a small pack with a down sleeping bag and a plaid, his hunting kit and a small toolbox (he had just finished his apprenticeship as a joiner) and he lived wild on Rannoch moor for nearly three years.
When he was fit enough he worked for the local farmers, and their wives saw him all right for oatmeal, eggs when the hens were laying, and tea, sugar and pipe tobacco. When he wasn't fit, he slept and drank teas made from myrtle, meadowsweet, etc.,
Mostly he hunted and gathered what he needed. He said he'd never been fitter in his life than he'd been when he came home from the moor. After he came home he started building boats and he was still drawing plans for them the night before he died.

No idea how clean the water there is now. There's a Youth Hostel at Ossian on Rannoch moor, maybe contact them and ask, they might know how safe the water is.
Hope you have an excellent trip.
Cheers,
Toddy

 

[Lost_Patrol]

Toddy,

He must have been tough to thrive up there in the winter. I'm way too soft for that but I'm looking forward to my visit. I'll try the Youth Hostel - Thanks for that

 

[Spikey DaPikey]

Maddave once told me, Big Bubbles, No Troubles

Boil it

 

[Ahjno]

The Katadyn Hiker doesn't removes viruses?
I am (was ...) saving up for that filter ... because information I had it should filter viruses too (actually: all the nasties) ... Double checked it on the Katadyn website, and Lost Patrol is right It doesn't remove viruses ...

Without hijacking the thread:
What filter does remove all the nasties? Does such a filter excist?
I might sounds a bit paranoia by wanting to remove all the nasties from my water, but that's for a good reason: I've got Crohn's disease (chronic infection of the bowel) - So I try to be on the save side as much as possible ...

Cheers

 

[Lost_Patrol]

As I understand it the Viruses are too small to filter out. Some of the filters (not the Katadyn hiker) have a filtering stage followed by an Iodine stage. The iodine is designed to chemically kill the viruses that have escaped the filter stage. As far as I know, there is no filter available that can filter the viruses due to their size.

Hope this is helpful.

 

[NickC]

I also have a Thyroid problem so have tried to find the same solution for some time - Something I discovered was that Pre-Mac (all Pre-Mac filter use iodine) offer a Outlet Filter which removes the Iodine. It does mean that you have to filter everything twice but I tend to use it only on drinking water - everything else is boiled. They dont advertise this (which is surprising since 10% of the population is supposed to have a thyroid problem) you have to phone and ask, but the price is cheaper than the normal filter.

Nick

 

[PC2K]

the First Need waterpurifier is the only purifier that will remove virusses without iodine. Atleast thats what they claim.

Virusses are very fragile things that can not life without a host for long periodes of time. Unless you are in the topica area, you'r pretty safe.

 

[The General]

What are the general opinions on tablets like Puritabs? I normally boil for 5 mins and when cool, put into bottle and drop a puritab in.

 

[bambodoggy]

What are the general opinions on tablets like Puritabs? I normally boil for 5 mins and when cool, put into bottle and drop a puritab in.

Sounds a bit like over kill to me General... in the mountains I drink from wherever I choose (I am careful which steams and springs I use and tend to fill up on my way downsteam so I have a better understanding of what is up stream as that's where I came from ) and in the lowlands I filter if required with a millbank bag to remove the larger debris and then either use my filter straw or more often than not just drop a puritab in it and crack on. I do the same in other parts of the world and simply add more puritabs the more disgusting the water looks...that's what I was taught to do and it's worked for me I've never been ill from drinking water anywhere in the world...

In a fixed camp I have been known to boil water but to be honest I find it a pain and even more so when I'm on the move so I avoid it if possible. The only time I really boil water is to make coffee

I did once get giardia in spain....from a swimming pool no less, my whole family got it and it's not nice, lasted me and dad about three weeks and mum nearly two months! Don't recomend it....won't go into details

So, 5 mins boil and a puritab sounds pretty bomb proof to me General but I don't have time to mess about with all that usually, there's too many other things to see and do

Bam.

 

[Doc]

Typhoid is not caused by a virus. It is caused by a bacterium, Salmonella typhi.

Some waterborne viruses are reasonably environmentally robust (polio, hepatitis A, norovirus) and it is not safe to assume that they are too fragile to survive in the environment in Scotland. You are probably more at risk from other pathogens though. Most waterborne virus outbreaks have been from sewage contamination of drinking water (cases reported from Finland and Ireland) and I couldn't find any helpful information about the likely risk from hill streams.

I had always understood that only reverse osmosis filters (very bulky) would remove viruses. However, the First Need website does indeed claim 99.99% eradication of rotavirus. However, norovirus is about half the size of rotavirus, and it is interesting to note that the respected Centre for Disease Control in Atlanta are a bit wary of the effectiveness of filters in removing waterborne viruses. http://www2.ncid.cdc.gov/travel/yb/...ecs&obj=food-drink-risks.htm&cssNav=browsecyb

Trail Walker tested water from mountain streams in the Lake District. All had sufficient numbers of coliform (faecal) bacteria that they would not meet drinking water standards. I have often drunk from Scottish burns without ill effect. However, if you are going somewhere remote (and the islands of Loch Laidon is pretty remote) then getting severe diarrhoea could be a serious problem. I no longer drink untreated water when on more than a day trip.

Chlorine (eg Puritabs) are of limited effectiveness against giardia, cryptosporidium, norovirus and to some extent Hepatitis A. Iodine is better, but still unreliable against cryptosporidium.

Boiling is very effective, except for chemical contamination. You are unlikely to have problems with chemical contamination on Rannoch moor and the canoe allows you to carry extra fuel for boiling. (A fire might be possible, Rannoch being littered with old pine stumps in the bog. The islands have remnants of the great Caledonian forest - so much care is needed.)

When backpacking, I use the tiny pre-mac job. Weighs 60grams, treats 100litres (RAF tested it and found it ok, despite being rated for 50l)

 

[Wayland]

Have you thought about Aquamira?

It's Iodine & Chlorine free but kills most things including E.coli, Hepatitis A, Poliovirus, Gardia & Cryptosporidium.

I run the water through a milbank bag first if it's not too clear but most times I does the job on it's own.

 

[Rod]

For what it's worth...

I got into a conversation with a Doctor in an outdoor shop who was adament that only a rolling boil makes water safe to drink (except where there is chamical contamination - as Doc has already mentioned).

I can't say I have ever had the squits out in the mountains and I have taken water from streams and springs throughtout the UK for most of my life. I have only drunk directly from a stream once, below Buchaille Etive Mor, that was in an emergency a couple of years back and it was in winter. (It was drummed into me as a youngster that there could be a dead sheep etc just upstream from where you were thinking of drawing water)

If in doubt - boil it

 

[g4ghb]

I started live as a microbiologist and we used to filter sterilise some things as they were affected by heat!

I'm racking my brain to remember the filter size but 0.47micron seems to ring a bell! - thats darned small and hard to push liquid through! - let alone trying to suck!

I'm always concerned re filtering purely from this reason - plus when I remember we would autoclave routeenly for 15 mins at 15psi (approx 121'C) just plain boiling seems minimalistic however having said that that's all i do and i've never had any problems any problems any problems

 

[leon-1]

For what it's worth...

I got into a conversation with a Doctor in an outdoor shop who was adament that only a rolling boil makes water safe to drink (except where there is chamical contamination - as Doc has already mentioned).

If in doubt - boil it

The Regimental Water Duties course run in Ash Vale by the RAMC say that if you are to use boiling as a method of sterilisation, that the water should be kept at a rolling boil for 10 minutes.

So for my moneys worth I agree with Rod.

But this would be worth your time reading, I may not fully agree with what they say about boiling (1 minute), but the rest of it is pretty good and it is nhs scotland that published it.