SteriPEN treats a wide variety of bacteria, viruses and protozoan cysts, such as:

Bacteria - These guys may be teeny tiny, but they can do some major damage. Ever heard of necrotizing fasciitis? How about if we call it Flesh Eating Bacteria? And bacteria's right in the name!
Campylobacter - Campers beware, campylobacter is the leading cause of bacterial diarrhea...and it's found everywhere!
Cholera - Little Timmy might have died from this in the Oregon Trail game, but it's very real. Cholera infects the intestines and while it's rare in places with proper infrastructure, it can still be found in brackish rivers and coastal water.
Cryptosporidium - Like Cholera, these guys live in your intestines, but Cryptosporidium is a cyst
containing thousands of protozoan parasites! Now that's a one-way relationship you don't want to be a part of!

Escherichia coli - You know this one better as E. coli, and in most cases, he's on your side (and in your stomach). In healthy people, E. coli actually makes vitamins your body needs and helps keep more harmful bacteria in check. But watch out for the black sheep of the family, E. coli O157:H7. It may be rare, but this strain releases a powerful toxin that will damage the lining of the intestine and cause severe sickness.
Giardia – They say there’s lots of
fish in the sea, and with Giardia, it’s true – it’s found all over the world
and it one of the most common causes of waterbourne illnesses and THE most
common cause of non-bacterial diarrhea in North America. But at least if you
let this parasite into your life, it’ll be a give and take relationship - it’ll
take your small intestine for its home and give you a bad case of diarrhea in
return.
Hepatitis – You probably already know
you can catch Hepatitis by drinking alcohol or taking drugs from suspicious
sources, but this little virus can also live in your water. Luckily, the
SteriPEN can kill all six strains. How’s that for justice?

Legionella – You might think the water
in your hotel is safe, but that might not be the case. The ninja-like legionella
bacterium can hide out in larger organisms and fall though the cracks when your
water is disinfected in large water distribution centers like those in hotels
and even hospitals. And take it from us, you don’t want a legion of legionella
floating around inside your body!
Protozoan parasite – Protozoan
parasites represent a whole classification of nasty baddies who are live in the
cells and tissues of other living creatures and they’re looking to make you
their next host. Protozoans can cause a whole laundry list of problems, from
targeting the central nervous system to diarrhea. No matter your symptoms, you
don’t want one of these guys to be your guest.
Salmonella – When your mom told you not
to eat raw eggs, she was trying to save you from this bacterium, but salmonella
can also live in water (and animals…and dry environments…) for several months.
Salmonella can cause all sorts of diseases from typhoid fever to salmonellis,
none of which are much fun to have.

Shigella – Don’t let the name fool
you, shigella isn’t shy when it comes to getting to know a new host. Even just
a few bacterium can cause a infections like dysentery, shigellosis or hemolytic
uremic syndrome.
Viruses – Remember when we said bacteria
are tiny? Viruses are 100 times smaller than a single bacteria cell and they’re
so cut throat that they’ll hijack the cells of other organisms to help them do
things they can’t do on their own, like eat, grow and multiply...moochers!