Giardia

[snoboy]

danielpatricksmith said:

Also, for what it is worth, I found Giardia and cryptosporidium in every stream I tested, including streams in protected watersheds (pristine forests that the public is not allowed in to protect water quality). My results were similar to those of other reasearchers such as Ongerth and Le Chaviler.

 

Was it at "signifigant levels?" Where did you do this field work? Just curious.

[catbirdseat]

I remember reading about the test for giardia. It is quite primitive. It consists of putting large quantities of water through a filter and examining the filter under a microscope. It relys upon the tester being able to recognize the cysts among all the various and sundry other organisms and just plain junk in the filtrand. An inexperienced technician can miss organisms and get an undercount, and I suppose count harmless ones and produce an overcount, but I think the latter less likely.

[Tod]

danielpatricksmith said:

Also, for what it is worth, I found Giardia and cryptosporidium in every stream I tested, including streams in protected watersheds (pristine forests that the public is not allowed in to protect water quality). My results were similar to those of other reasearchers such as Ongerth and Le Chaviler.

Have you tested city water before? I thought it was very interesting in the research from the original post that San Francisco water had more giardia than the streams tested in the Sierras. I would have to agree that the testing methods used in the Sierras is probably not the most precise (since you can't pack in that much equipment), but if they were using the same testing methods to test San Francisco water and were consistently coming up with more giardia there I would expect that there is some truth.

 

Either way, the research still tells me that high mountain water is GENERALLY just as safe as city water (and safer than San Francisco water). This would be particularly true during spring run off since cysts can only survive for as long as 2 to 3 months in cold water and they cannot tolerate freezing. Let giardia sit in a lake from the onset of winter and 5-6 months later when it thaws out it's generally or completely free of giardia. But then again, all it takes is one infected/carrier gumby or animal pooping in the lake.

 

For me, I'll drink from most any high mountain stream, particularly if it's direct run off or from a spring. I've been doing this for 10 years on a regular basis and no problems. I'm not saying that all water is safe or that everybody should do what I do, but in my opinion (backed up by experience and independent research such as above), water filters for the alpinist are unneeded weight. Backpackers and lowland hikers are a different story....

[Mike]

I've had giardia twice, so I'm not an expert but I am experienced. The symptoms kick in usually 7-10 days after exposure and included sulphur burbs (like heartburn kind of) and EXPLOSIVE diarhea (you'll spray the back of the john). I think both cases were from contaminated dishwashing water - once in India and once in Nepal.

 

If you contract giardia overseas, look for a drug called Tinuba or Tinazedole (sp?). This is a drug which only cures giardia and has never been marketed in the US because there's no cost justification to conduct the FDA trials - not enough giardia here. Instead you'll get Flagyl which will make you sicker than a dog and eventually cure your giardia. Tinuba is cool because it cures your giardia in less than 24 hours with one dose, and I had no side effects either time. I buy some extra - just in case - everytime I can find it overseas.

[Mike]

BTW, buy some Tinuba in Kathmandu if you ever go trekking in Nepal. You may be exposed to giardia, and then it's hit or miss whether you can get it while out trekking. Only costs a buck or two, so it's cheap insurance.

[DPS]

"I remember reading about the test for giardia. It is quite primitive. It consists of putting large quantities of water through a filter and examining the filter under a microscope. It relys upon the tester being able to recognize the cysts among all the various and sundry other organisms and just plain junk in the filtrand. An inexperienced technician can miss organisms and get an undercount, and I suppose count harmless ones and produce an overcount, but I think the latter less likely"

 

What do you mean by primitive? Bacteria are still counted by culturing the organisms on a growth medium then counting the colonies that are formed, a process developed by Koch (a man of pure culture). The process for identifying and counting Giardia and Cryptosporidium is a multi step process that evolved in two different labs. Jerry Ongerth at the University of Washington developed a method for testing small volumes (~100 liters ) of water while Lechavalier at the University of Illinois (I think) developed a method for testing large volumes of water. Ongerth’s method was more efficient and had cyst recovery rates of up to 20%, while Lechavalier’s method produced a recovery rate of around 5%. (Recovery rates were determined by spiking a volume of water with a known quantity of Giardia cyst and then processing and comparing the number identified with the number added). The main difference between the two was Ongerth filtered water through a 293 mm Nucleopore ploycarbonate membrane (remember the old MSR waterworks?). The filter would eventually clog up limiting the volume that could be filtered. The membrane was rinsed off and the rinsate collected. Lechavalier filtered water through a wound polycarbonate depth filter. The filter then had to be chopped up in a blender, rinsed out and the rinsate collected.

 

The rinsate was centrifuged, concentrating the cysts, then the concentrate filtered again. The cysts and oocysts were captured on a 13mm Nucleopore polycarbonate filter. An epifluorescent stain that is conjugated to antibodies is applied. The stain is rinsed off. Since the stain is conjugated to antibodies, and the antibodies stick to antigens on the cyst surface, only the Giardia and Cryptosporidium cysts and oocysts are stained. Then a counter stain of ethidium bromide is applied. Ethidium bromide is a DNA stain which sticks to the DNA inside the cysts. Then you view the filter under a microscope with a fluorescent light source. The cysts and oocysts glow bright apple green with the bright red ‘eyes’ in the middle. Positive identification is made by viewing the organelles.

 

Over counts are possible by inexperienced technicians, but once you see what a cyst/oocyst looks like, its kind of hard to make a mistake. Either method grossly underestimates the number of organisms in the sample, however a correction factor can be applied based on the recovery rate of spiked positive control samples that are run in the same batch.

 

 

 

 

"Have you tested city water before? I thought it was very interesting in the research from the original post that San Francisco water had more giardia than the streams tested in the Sierras. I would have to agree that the testing methods used in the Sierras is probably not the most precise (since you can't pack in that much equipment), but if they were using the same testing methods to test San Francisco water and were consistently coming up with more giardia there I would expect that there is some truth.

 

Either way, the research still tells me that high mountain water is GENERALLY just as safe as city water (and safer than San Francisco water). This would be particularly true during spring run off since cysts can only survive for as long as 2 to 3 months in cold water and they cannot tolerate freezing. Let giardia sit in a lake from the onset of winter and 5-6 months later when it thaws out it's generally or completely free of giardia. But then again, all it takes is one infected/carrier gumby or animal pooping in the lake."

 

Keep in mind that chlorine will kill some of the cysts, particularly if there is a high enough residence time and it is difficult to differentiate an inactivated cyst from an active one. Even if the municipal water had more cysts, some of them would certainly be inactive, therefore it is erroneous to assume that mountain water is as same as municipal water. Also, don’t forget about bacteria. While I found at the most a few cysts per 100 liters, I found tens of thousands of colony forming fecal coliform units per 100 mls in many of the samples.

 

I have not read the entire article, but so far I have found it to be poorly researched, poorly referenced, and contained many glaring errors. I started reading this and I wondered how a pHD could publish such a piece of crap, then I read his bio. He is an engineer. Engineers make the worst biologists. Towards the end of the article he recommends drinking from fast moving water. This makes absoultely no sense. Giardia and Cryptosprodium are more dense than water and will sink unless suspended by turbulence. Better to get your water from a calm spot.

Edited June 18, 2003 by danielpatricksmith

[Thinker]

Mike said:

I've had giardia twice, so I'm not an expert but I am experienced. The symptoms kick in usually 7-10 days after exposure and included sulphur burbs (like heartburn kind of) and EXPLOSIVE diarhea (you'll spray the back of the john). I think both cases were from contaminated dishwashing water - once in India and once in Nepal.

 

If you contract giardia overseas, look for a drug called Tinuba or Tinazedole (sp?). This is a drug which only cures giardia and has never been marketed in the US because there's no cost justification to conduct the FDA trials - not enough giardia here. Instead you'll get Flagyl which will make you sicker than a dog and eventually cure your giardia. Tinuba is cool because it cures your giardia in less than 24 hours with one dose, and I had no side effects either time. I buy some extra - just in case - everytime I can find it overseas.

 

Can one purchase Tinuba in Canada?

[Thinker]

Tod said:

 

Have you tested city water before? I thought it was very interesting in the research from the original post that San Francisco water had more giardia than the streams tested in the Sierras. I would have to agree that the testing methods used in the Sierras is probably not the most precise (since you can't pack in that much equipment), but if they were using the same testing methods to test San Francisco water and were consistently coming up with more giardia there I would expect that there is some truth.

 

Either way, the research still tells me that high mountain water is GENERALLY just as safe as city water (and safer than San Francisco water). This would be particularly true during spring run off since cysts can only survive for as long as 2 to 3 months in cold water and they cannot tolerate freezing. Let giardia sit in a lake from the onset of winter and 5-6 months later when it thaws out it's generally or completely free of giardia. But then again, all it takes is one infected/carrier gumby or animal pooping in the lake.

 

For me, I'll drink from most any high mountain stream, particularly if it's direct run off or from a spring. I've been doing this for 10 years on a regular basis and no problems. I'm not saying that all water is safe or that everybody should do what I do, but in my opinion (backed up by experience and independent research such as above), water filters for the alpinist are unneeded weight. Backpackers and lowland hikers are a different story....

 

If memory serves me correctly, the Hetch Hetcy reservoir in Yosemite provides much of San Francisco's drinking water and is not treated in any way between the res and the tap. That's why the city of SF tries to limit the amount of human activitiy around the res. However, it doesn't surprise me to hear that a little cryto and G slip into the drinking water anyway.

[DPS]

The City of Seattle is similar to San Francisco in that they do not filter the drinking water. They just add a bit of chlorine and send it on its way. City of Seattle gets its water from three watersheds, the Tolt, the Green and the Cedar. Two are protected, one is not. The protected watersheds were found by Ongerth have statistically significant lower concentrations of Girdia and Cryptosporidium than the unprotected watersheds.

[lummox]

Mike said:

EXPLOSIVE diarhea

[Thinker]

danielpatricksmith said:

The City of Seattle is similar to San Francisco in that they do not filter the drinking water. They just add a bit of chlorine and send it on its way. City of Seattle gets its water from three watersheds, the Tolt, the Green and the Cedar. Two are protected, one is not. The protected watersheds were found by Ongerth have statistically significant lower concentrations of Girdia and Cryptosporidium than the unprotected watersheds.

 

Several of my coworkers regularly scuba dive in our drinking water at three of the reservoirs. The powers that be take their watershed protection pretty seriously to avoid microbiological contamination and to avoid the expense of installing filtration equipment.

 

Bottoms up!

[Mike]

Thinker: I don't know if you can get it in Canada, but you could try checking. It would probably require a doctors prescription. Mexico would probably be better, because they probably have more contaminated water and you might be able to purchase over the counter from a pharmacist.

 

Lummox: seriously explosive - lot's of gas. That's where the sulphur burbs come from too.

[tshimko]

For the record, I'm the same guy that danielpatricksmith ran into recently. The testing failures of the Sweetwater and PUR products refers only to the ability of the iodinated resin to deal with virus. The Sweetwater filter is quite effective when dealing with the larger microorganisms such as bacteria and the cysts (Giardia et al).

 

DPS's statement about the PUR iodinated resin products not having enough residence time is dead on. Same for theold Sweetwater viral product

 

Previous statements about PUR's claims as to not clogging also extend to them not being as effective as they should be against bacteria and Giardia in the long run.

 

BTW, my having left Cascade had nothing to do with the filter product. The Current Cascade product, the same old Sweetwater filter, is very effective against bacteria and Giardia (et al) and the viral product, called ViralStop is very effective against virus. I know....I developed the ViralStop.

 

If I was to recommend a filter product, the Sweetwater and MSR products are the best out there, both in terms of microbiological effectiveness, and in terms of field maintainability. And I say that based on objective criteria, not because I used to work there.

 

A tech tip for owners of these filters...if you pump a lot of "tea colored" water, eventually you'll come to a point where the normal cleaning will not restore flow. Unlike "dirt", the organics in the brown water (and even in clear water as well) penetrate deeper into the filter media, and are not easily cleaned like "dirt", which tends to remain on the surface of the filter media. To clean organics, add about 2 ounces of bleach (no soap, no scent, no anything else...) to a liter of water (more is NOT better), and pump the dilute bleach throught the filter slowly, and then leave the the last bit of dilute bleach in the filter overnight. Flush with clean water the next day (3-5 liters). Will be almost as good as new.

 

DPS...chlorine dioxide is not all that the product is claimed to be. I'd stick with iodine, my homemade version which delives 8-10 milligrams of iodine per drop. One drop/liter.

 

Also, I'd be interested in your data on Giardia in streams...where, how much, you know, all that good data stuff.

[Pencil_Pusher]

catbirdseat said:

One way you can get giardia on a climbing trip is the following. Climbing partner is a carrier. Partner doesn't wash hands after defacating. You offer some gorp to partner. Partner reaches unwashed hands into gorp bag, contaminating said gorp. You eat gorp. You get giardia and blame it on the water.

 

Thank you for that lovely example.

[kmurray]

danielpatricksmith said

=======

I did my graduate research on Giardia and Cryptosporidium 10 years ago.

=========

Where was this research published?

 

Also,

=======

Someone commented: "I remember reading about the test for giardia. It is quite primitive."

And dps responded:

"What do you mean by primitive?"

=========

 

It is hard to imagine a more primitive system of doing a lab test than the truly obscure stuff that you mention. That, of course, is typical of someone who has no clue about real-world human laboratory testing, and is confined to a basement to have the luxury of taking, say, a month to get a result.

Those of us who are skilled in running a human clincal lab, and doing clinical testing in the real world, laugh at the characterization of such testing as anything but approaching third world technology. There are so many places for error to be introduced, it is not even funny.

=========

Finally,

"I have not read the entire article, but"

Do you also do film reviews of pictures you have not seen? I can't imagine an institution that would have as a graduate student, a person who doesn't read a paper fully, then publishes a criticism of that paper. Any image of scientific credibility would seem to go out the window!

 

[Dru]

loks like kmurray woke up on the wrong side of bed

[vegetablebelay]

Or the wrong part of the country.

[DPS]

"Where was this research published?"

 

Journal of Applied and Environmental Microbiology

 

"It is hard to imagine a more primitive system of doing a lab test than the truly obscure stuff that you mention. That, of course, is typical of someone who has no clue about real-world human laboratory testing, and is confined to a basement to have the luxury of taking, say, a month to get a result.

Those of us who are skilled in running a human clincal lab, and doing clinical testing in the real world, laugh at the characterization of such testing as anything but approaching third world technology. There are so many places for error to be introduced, it is not even funny."

 

Clearly you are ignorant to the methodology used to examine water. The methods that you refer to as "truly obscure stuff" are described fully in 'Standard Methods for the Examination of Water and Wasterwater' published jointly by the Water Environment Federation, the American Water Works Association, and the American Public Health Association. These methods are used by virtually every lab in the country that does water testing.

 

Surely you should know that the methodology used for human clinical work is not applicable to environmental work. I know this because I worked in a human clinical lab (BFD, takes very little skill).

 

"Do you also do film reviews of pictures you have not seen? I can't imagine an institution that would have as a graduate student, a person who doesn't read a paper fully, then publishes a criticism of that paper. Any image of scientific credibility would seem to go out the window!"

 

What paper? I saw no published paper. What was published was one layman's opinions on the internet. What was published on the internet would not have stood up to peer review. I did indeed read the article in its entirety and I stand by my critism. And I walk out on bad movies.

 

And finally, you have a huge stick up your ass.

 

[catbirdseat]

DPS, you da man when it comes to giardia. Based on what I've learned, I'll pay more attention to hygiene and less attention to the water.

 

Do they sell tinadazole in Canada?

[Dru]

Hey i used to date Tina Dazole!

[Rodchester]

And finally, you have a huge stick up your ass.

 

[catbirdseat]

Here are your treatment choices:

Nitroimidizoles: Metronidazole, Flagyl®

Tinidazole, Fasigin®, Fasigyn®

Benzimidazoles: Albendazole

Mebendazole

Fenbendazole(?)

and Quinine analogues:

Quinacrine, Atebrine®

Quinine

Mefloquine (Larium®)

 

Tinidazole is not available in Canada, but it is in Mexico.

 

http://www.aidsinfonyc.org/pwahg/info/tini.html

Edited June 24, 2003 by catbirdseat

[cjain]

It's good to see that Robert Rockwell's paper, _Giardia Lambia and Giardia with Particular Emphasis to the Sierra Nevada_, is still generating vigorous debate long after it originally came out. Bob has recently made substantial revisions to this paper and the revised version is available at the California Mountaineering Club web site at www.californiamountaineer.com .

 

In an email to me, Bob summarized the revised paper as follows:

 

"It’s about 1/3 longer and has about 1/3 more references (over 500 KB now). Most of the new research and data reinforce the earlier findings so if they were on a solid basis before, they are even more so now.

 

"But there is new information, too. The immunity question is explored further. I have included some data on municipal drinking water problems, to make the point that a person who feels the need to sterilize Sierra water is not acting sensibly if he drinks his home tap water without treating it. The problem of Giardia in pets is new. I've elaborated a little on “drinking smart.”

 

"There are a number of smaller improvements, to add or reduce emphasis here and there, or to make things clearer.

 

"Finally, I've made the “closing arguments” more forceful, in the probably vain hope that the USFS and NPS will rethink the recommendations they provide to wilderness visitors."

 

 

[kmurray]

"Where was this research published?"

 

Journal of Applied and Environmental Microbiology

=================

 

Excellent, an obscure journal, where it made NO contribution to what people do in the real world. Can't remember the last time that I saw something reported in the lay press, from findings in that journal.

============

 

"It is hard to imagine a more primitive system of doing a lab test than the truly obscure stuff that you mention. That, of course, is typical of someone who has no clue about real-world human laboratory testing, and is confined to a basement to have the luxury of taking, say, a month to get a result.

Those of us who are skilled in running a human clincal lab, and doing clinical testing in the real world, laugh at the characterization of such testing as anything but approaching third world technology. There are so many places for error to be introduced, it is not even funny."

 

Clearly you are ignorant to the methodology used to examine water. The methods that you refer to as "truly obscure stuff" are described fully in 'Standard Methods for the Examination of Water and Wasterwater' published jointly by the Water Environment Federation, the American Water Works Association, and the American Public Health Association. These methods are used by virtually every lab in the country that does water testing.

===========

 

 

Clearly, you are ignorant to sophisticated methods of laboratory evaluation. Clearly, you have not worked in a lab subject to mandatory evaluation of their accuracy and precision on blind assays. I don't dispute that the methodology is common, nor that it is accepted.....the original poster simply described it as primitive, and I agree.

 

============

 

Surely you should know that the methodology used for human clinical work is not applicable to environmental work. I know this because I worked in a human clinical lab (BFD, takes very little skill).

==========

 

Surely you know that the methodology used for environmental work is not applicable to human clinical work. Problem is, that most of the posters here are human, and what concerns us is what happens to humans.

 

BTW, I know that you did NOT work in a human clinical lab doing parasite identification, because that takes a license to do. Simply because you washed glassware or logged specimens does not make you an expert in assessing the skill of people doing a job that you are not legally qualified to do. "No, I'm not a doctor, but I play one on television" doesn't quite work.

==========

 

"Do you also do film reviews of pictures you have not seen? I can't imagine an institution that would have as a graduate student, a person who doesn't read a paper fully, then publishes a criticism of that paper. Any image of scientific credibility would seem to go out the window!"

 

What paper? I saw no published paper. What was published was one layman's opinions on the internet. What was published on the internet would not have stood up to peer review. I did indeed read the article in its entirety and I stand by my critism. And I walk out on bad movies.

=========

Let me quote you: "I have not read the entire article"

So if my criticism of what you said was wrong, because you did not tell the truth, then I apologize.

 

You may walk out on bad movies, but if you hold yourself out to be a critic, you better not do that, and then criticize that which you have not seen. That is simple dishonesty.

 

If you want to parse words by trying to define, for the largely lay audience here, the difference between an article and a paper, then go ahead. Frankly, I doubt that anyone cares.

===========

And finally, you have a huge stick up your ass.

==========

 

That sounds like a productive way to convince others that you are correct in your assertions. Personally, I find that when people revert to personal attacks, it is because they cannot attack the arguments, and so, they have to attack the person, because they have been so insulted as to actually have their assertions questioned.

For example, you say: "contained many glaring errors"

But you do not list or discuss these. Everyone is just supposed to take your word for this? You seem to want to trash the "article" that was written, but what, about the point of the article, do you take issue with? You could take a productive path, contact the author, and make helpful suggestions as to how to make the information better. The author, Rockwell (who I do not know), has and is, making a significant contribution to the outdoor community. What are you contributing, other than sniping remarks?

If you are incapable of discussing your assertions without launching into attacks upon people who question your statements, perhaps you better let the adults do the talking.

[DPS]

Just because you have not heard about the journal does not make it obscure. Quite on the contrary, this journal, along with Journal of the American Water Works Association is where most of the Giardia and Cryptpsporidium research has been published and has had important impacts on public policy and the way municipal treatment plants do their business.

 

Actually, I have worked in a lab subject to mandatory evaluation of its accuracy and precision on blind assays. No, I did not do paristology work on human specimens (much easier than doing it in environmental samples, license or no) I worked on human drug trials for a lipid therapy treatment of Type II diabetes.

 

The author of the paper is actually doing a huge diservice to the community by publishing information that is just plain wrong and his own conclusions based on the fact that he has never exhibited symptoms of the disease.