How much of an issue is waterborne tapeworm?

10:49 p.m. on June 4, 2013 (EDT)
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Got a trip to Isle Royale in Lake superior planned in a couple of weeks.  Noticed that they have waterborne tapeworms there.  Normally, I use a Steripen as my primary water purification method anytime I'm going somewhere that relatively clear water is expected.  Unfortunately, Steripen does not recommend UV treatment to make water safe that may have worm eggs.

Because of this I'll be bringing my Miniworks filter, but that got me thinking, are there any other areas in the US or Canada where waterborne worm eggs are likely?  I do quite a bit of backpacking in northern MN and am wondering if it's an issue there or anywhere else.   

7:33 a.m. on June 5, 2013 (EDT)
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Your best bet for eggs is indeed mechanical filtration. You never really know what water is infected with them or not, but I know Isle Royale area is known for them. As are alot of areas in and near Mexico. Not sure of any other areas, but i am sure there are others. There are hundreds or maybe even thousands of worm eggs in just a handful of topsoil, i guess its just luck of the draw if one of them is a tapeworm.

UV treatment may work.....or it may not. I would suspect that a double treatment would do the job based off the research Steripen mentions below. However, eggs are tricky because the "shell" protects them from the outside world. Shell is not always a hard shell like a chicken either. I would be hesitant to use known infected water without boiling, mechanical filtration, or proven effective UV treatment.

A tapeworm egg, and most worm eggs in general, are about the size of a grain of sand, so around 1mm. These can be removed by most any prefilter device such as a coffee filter, and actual filters such as msr miniworks, sawyer squeeze etc.

On a side note, if you do find yourself infected, or if your just really paranoid. Eat a teaspoon of food grade DE to deworm yourself after your trip, haha. Works on dogs, and all manner of livestock. Even humans! Better than the chemical cocktail your doctor will shoot you up with.

This is from the steripen website:

46. Is the SteriPEN effective against worm eggs?

We have tested SteriPEN only against bacteria, viruses and the protozoa Cryptosporidium and Giardia. We have never tested against worm eggs so unfortunately we cannot give a definite answer with regards to UV treatment in this case. As to our pre-filter we do not make microbiological claims about it as it is really just intended to remove large particulates. The pore size is 4 microns by 4 microns square, it is a nylon material comparable to a coffee filter.
While there is not a lot of literature in UV treatment of worm eggs, you may be interested in this Parasitology Researchwebsite.
When reading this keep in mind that the UV wavelengths emitted by SteriPEN are in the Mercury band with a primary energy output at 254 nanometers (in the UV-C range). Also, SteriPEN?s 1 liter treatment time is 90 seconds and generally delivers over 100 milijoules/ during this dose. Below is a quote from the above site:
"The UVC lamp significantly inhibited the infectivity of taeniid eggs in rats. The Bonferroni/Dunn test for the mean number of cysts in the control group and the groups exposed to the UVC lamp was significant ( P<0.0001), except for the group at an exposure of 30 s (30 mJ/cm 2 at 254 nm). This means that the significant effect of the UVC lamp commences at exposure duration of 90 s (90 mJ/cm 2 at 254 nm)."
So, in a nutshell, we are sorry that we cannot specifically point you to SteriPEN testing on worm eggs. 

1:32 p.m. on June 5, 2013 (EDT)
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definitely use the filter!

1:00 a.m. on June 9, 2013 (EDT)
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Echinococcus granulosus cysts are ~35um in (thousanth of a mm) diameter. 

Seems to me that mechanical filtration is the only way to prevent infection... keeping food away from soil and vegetation. Hope this helps. Helminths are really ugly little bastards. Gar

The website here will not allow me to post the URL references.... 

go to

cdc/parasite  and or google this little buggers name.

1:45 p.m. on June 11, 2013 (EDT)
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Thanks although I was asking if anyone knew of areas where waterborne worm eggs were an issue and not whether or not I should use a steripen.


2:51 p.m. on June 11, 2013 (EDT)
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I don't know of any other place than the great lakes region where tapeworms are a problem, but I could be wrong. your just going to have to research it, I guess.

June 21, 2018
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