Do You Have a Water Purifier?
Kevin Felts 10.31.17
When hiking or camping, do you bring a water filter, a water purifier, or both? Someone may be asking, “You can have a water filter and a separate water purifier?” Sure you can, and it is easier than most people think.
There are more water filters on the market than someone can shake a stick at. On top of that, the differences between filters and purifiers can be confusing.
For the sake of this article we will focus on hiking and camping in North America. Also, the word “bacteria” will be used as a generic term to describe bacteria, cysts, and protozoa.
Filter or Purifier
It is easy for people to get confused on the terms “water filter” and “water purifier.”
Think of it this way:
- Filter – Removes bacteria but does nothing to a virus.
- Purifier – Removes or kills viruses and bacteria.
The Center for Disease Control (CDC) says for a filter to stop a virus, it must be no larger than 0.01 microns, absolute.
From the CDC: Water Disinfection for Travelers.
Viruses
Average size: 0.03
MAXIMUM RECOMMENDED FILTER RATING (µm ABSOLUTE),
Not specified (optimally 0.01, ultrafiltration).
Most filters on the market have a rating of 0.1 microns. This means a virus will slip right through. However, viruses can be killed with stuff like chemicals and ultraviolet (UV) light.
On a personal note, when in doubt I use a SteriPEN to purify the water. First it is run through a filter, then a SteriPEN is used on it. The end result is water that has been filtered and purified.
How Common Are Viruses?
One of the big questions is, “How likely is there to be a virus in the water?”
For that answer we turn to the CDC and a Morbidity and Mortality Weekly Report published in 2008.
Page 12, figure 5.
Etiologic agent: untreated water.
- E. coli O157:H7: 23.1%
- Shigella sonnei: 23.1%
- >Norovirus: 23.1%
- Cryptosporidium spp: 15.4%
- Unidentified: 15.4%
Further reading of the report shows a number of those Norovirus cases were related to swimming pools, such as hotel pools. Other cases are related to floodwater exposure. Not exactly the types of stuff hikers and campers usually run into.
What about Polio?
The United States has been Polio-free since 1979.
Thanks to effective vaccine, the United States has been polio-free since 1979. But poliovirus is still a threat in some countries. Be part of the success story and get your child vaccinated on schedule.
Polio, or poliomyelitis, is a crippling and potentially deadly infectious disease. It is caused by the poliovirus. The virus spreads from person to person and can invade an infected person’s brain and spinal cord, causing paralysis (can’t move parts of the body).
However, in 2005 there was an outbreak of Polio in an Amish community.
Final Thoughts
I am not a health professional, nor do I claim to be one. What I can do however, is present evidence I have collected over the past few years.
While on a multi-day camping trip downstream from people who use septic systems, I filtered, and then purified with UV light.
When hiking or camping there is one simple question I ask myself, “Are you in doubt?” If so, purify.
