Preventing cryptosporidiosis
A guide for persons with compromised immune systems
August 2005 View PDF
Reprinted from www.cdc.gov,
US
How can I protect myself from crypto?
You can reduce your risk of getting Crypto. The more steps you
take, the less likely you are to get infected. These actions will
also help protect you against other diseases. Following all the
recommendations in this fact sheet can be a great personal burden.
Consult with your health care provider to determine whether your
medical condition makes it advisable to follow all of these recommendations.
1. Wash your hands.
Washing your hands often with soap and water is probably the single
most important step you can take to prevent Crypto and other illnesses.
Always wash your hands before eating and preparing food. Wash your
hands well after touching children in diapers; after touching clothing,
bedding, toilets, or bed pans soiled by someone who has diarrhea;
after gardening; any time you touch pets or other animals; and after
touching anything that might have had contact with even the smallest
amounts of human or animal stool, including dirt in your garden
and other places. Even if you wear gloves when you do these activities
you should still wash well when you finish. Children should be supervised
by adults to make sure they wash their hands well.
2. Practice safer sex.
Infected people may have Crypto on their skin in the anal and genital
areas, including the thighs and buttocks. However, since you cannot
tell if someone has Crypto, you may want to take these precautions
with any sex partner: "Rimming" (kissing or licking the
anus) is so likely to spread infection that you should avoid it,
even if you and your partner wash well before. Always wash your
hands well after touching your partner's anus or rectal area.
3. Avoid touching farm animals.
If you touch a farm animal, particularly a calf, lamb, or other
young animal, or visit a farm where animals are raised, wash your
hands well with soap and water before preparing food or putting
anything in your mouth. Do not touch the stool of any animal. After
you visit a farm or other area with animals, have someone who is
not immunocompromised clean your shoes, or wear disposable gloves
if you clean them yourself. Wash your hands after taking off the
gloves.
4. Avoid touching the stool of pets.
Most pets are safe to own. However, someone who is not immunocompromised
should clean their litter boxes or cages, and dispose of the stool.
If you must clean up after a pet, use disposable gloves. Wash your
hands afterwards. The risk of getting Crypto is greatest from pets
that are less than 6 months old, animals that have diarrhea, and
stray animals. Older animals can also have Crypto, but they are
less likely to have it than younger animals. If you get a puppy
or kitten that is less than 6 months old, have the animal tested
for Crypto before bringing it home. If any pet gets diarrhea, have
it tested for Crypto.
5. Avoid swallowing water when swimming
in
the ocean, lakes, rivers, or pools, and when using hot tubs.
When swimming in lakes, rivers, or pools, and when using hot tubs,
avoid swallowing water. Several outbreaks of Crypto have been traced
to swallowing contaminated water while swimming. Crypto can live
in chlorinated swimming pools and waterparks for days. Crypto also
can remain alive in salt water for several days, so swimming in
polluted ocean water may also be unsafe.
6. Wash and/or cook your food.
Fresh vegetables and fruits may be contaminated with Crypto. Therefore,
wash well all vegetables or fruit you will eat uncooked. If you
take extra steps to make your water safe (see below for ways to
do so), use this safe water to wash your fruits and vegetables.
When you can, peel fruit that you will eat raw, after washing it.
Do not eat or drink unpasteurized milk or dairy products. Cooking
kills Crypto. Therefore, cooked food and heat-processed foods are
probably safe if, after cooking or processing, they are not handled
by someone infected with Crypto, or exposed to possibly contaminated
water.
7. Drink safe water.
Do not drink water directly from lakes, rivers, streams, or springs.
Because you cannot be sure if your tap water contains Crypto, you
may wish to avoid drinking tap water, including water or ice from
a refrigerator, which is usually made with tap water. Because public
water quality and treatment vary throughout the United States, always
check with the local health department and water utility to see
if they have issued any special notices about the use of tap water
by immunocompromised persons. You may also wish to take some additional
measures: boiling your water, filtering your water with certain
home filters, or drinking certain types of bottled water. Processed
carbonated (bubbly) drinks in cans or bottles are probably safe,
but drinks made at a fountain might not be because they are made
with tap water. If you choose to take these extra measures, use
them all the time, not just at home. If the public health department
advises boiling the water, do not drink tap water unless you boil
it. You could also use one of the bottled waters described below.
A. Boiling water: Boiling is the
best extra measure to ensure that your water is free of Crypto and
other germs. Heating water at a rolling boil for 1 minute kills
Crypto, according to CDC* and EPA** scientists. After the boiled
water cools, put it in a clean bottle or pitcher with a lid and
store it in the refrigerator. Use the water for drinking, cooking,
or making ice. Water bottles and ice trays should be cleaned with
soap and water before use. Do not touch the inside of them after
cleaning. If you can, clean water bottles and ice trays yourself.
B. Filtering tap water: Not all
available home water filters remove Crypto. All filters that have
the words "reverse osmosis" on the label protect against
Crypto. Some other types also work, but not all filters that are
supposed to remove objects 1 micron or larger from water are the
same. Look for the words "absolute 1 micron." Some "1
micron" and most "nominal 1 micron" filters will
not work against Crypto. Also look for the words "Standard
53" and the words "cyst reduction" or "cyst
removal" for an NSF-tested filter that works against Crypto.
To find out if a particular filter removes Crypto,
contact NSF International (3475 Plymouth Road, P.O. Box 130140,
Ann Arbor, MI 48113-0140, tel: 1-800-673-8010, fax: 1-313-769- 0109),
an independent testing group. Ask NSF for a list of "Standard
53 Cyst Filters." Check the model number on the filter you
intend to buy to make sure it is exactly the same as the number
on the NSF list. Look for the NSF trademark on filters, but be aware
that NSF tests filters for many different things. Because NSF testing
is expensive, many filters that may work against Crypto have not
been tested. Reverse-osmosis filters work against Crypto whether
they have been tested by NSF or not. Many other filters not tested
by NSF also work if they have an absolute pore size of 1 micron
or smaller.
Filters designed to remove Crypto:
(any of the four messages below on a package label indicate that
the filter should be able to remove Crypto)
- Reverse-osmosis (with or without NSF testing)
- Tested and certified by NSF Standard 53 for cyst removal
- Tested and certified by NSF Standard 53 for cyst reduction
- Absolute pore size of 1 micron or smaller (with or without NSF
testing)
Filters labeled only with these words may not be
designed to remove Crypto:
- Nominal pore size of 1 micron or smaller
- 1-micron filter
- Effective against Giardia
- Effective against parasites
- Carbon filter
- Water purifier
- EPA approved - Caution: EPA does not approve or test filters
- EPA registered - Caution: EPA does not register filters for
Crypto removal
- Activated carbon
- Removes chlorine
- Ultraviolet light
- Pentiodide resins
- Water softener
Filters collect germs from your water, so someone
who is not immuncompromised should change the filter cartridges
for you; if you do it yourself, wear gloves and wash your hands
afterwards. Filters may not remove Crypto as well as boiling does
because even good brands of filters may sometimes have manufacturing
flaws that allow small numbers of Crypto to get past the filter.
Also, poor filter maintenance or failure to replace filter cartridges
as recommended by the manufacturer can cause your filter to fail.
C. Bottled water: If you drink
bottled water, read the label and look for this information:
Water so labeled has been processed by method effective
against Crypto:
- Reverse-osmosis treated
- Distilled
- Filtered through an absolute 1 micron or smaller filter
- "1-micron absolute"
Water so labeled may not have been processed by
method effective against Crypto:
- Filtered
- Micro-filtered
- Carbon-filtered
- Particle-filtered
- Multimedia-filtered
- Ozonated
- Ozone-treated
- Ultraviolet light-treated
- Activated carbon-treated
- Carbon dioxide-treated
- Ion exchange-treated
- Deionized
- Purified
- Chlorinated
Bottled water labels reading "well water,"
"artesian well water," "spring water," or "mineral
water" do not guarantee that the water does not contain Crypto.
However, water that comes from protected well or protected spring
water sources is less likely to contain Crypto than bottled water
or tap water from less protected sources, such as rivers and lakes.
Any bottled water (no matter what the source) that has been treated
by one or more of the methods listed in the top part of the water
filters table is considered safe.
D. Home distillers: You can remove
Crypto and other germs from your water with a home distiller. If
you use one, you need to carefully store your water as recommended
for storing boiled water.
E. Other drinks: Soft drinks and
other beverages may or may not contain Crypto. You need to know
how they were prepared to know if they might contain Crypto.
If you drink prepared drinks, look for drinks prepared
to remove Crypto:
Information on Prepared Drinks:
- Crypto killed or removed in preparation
- Canned or bottled soda, seltzer, and fruit drinks
- Steaming hot (175 degrees F or hotter) tea or coffee
Pasteurized drinks:
- Crypto may not be killed or removed in preparation
Fountain drinks:
- Fruit drinks you mix with tap water from frozen concentrate
- Iced tea or coffee
Juices made from fresh fruit can also be contaminated
with Crypto. Several people became ill after drinking apple cider
made from apples contaminated with Crypto. You may wish to avoid
unpasteurized juices or fresh juices if you do not know how they
were prepared.
8. Take extra care when traveling.
If you travel to developing nations, you may be at a greater risk
for Crypto because of poorer water treatment and food sanitation.
Warnings about food, drinks, and swimming are even more important
when visiting developing countries. Avoid foods and drinks, in particular
raw fruits and vegetables, tap water, or ice made from tap water,
unpasteurized milk or dairy products, and items purchased from street
vendors. These items may be contaminated with Crypto. Steaming-hot
foods, fruits you peel yourself, bottled and canned processed drinks,
and hot coffee or tea are probably safe. Talk with your health care
provider about other guidelines for travel abroad.
For more information on Crypto, call
the CDC National HIV and AIDS Hotline at 1-800-342-AIDS.
This information was prepared by the inter-agency
Working Group on Waterborne Cryptosporidiosis, which includes
representatives from the Centers for Disease Control and Prevention,
Environmental Protection Agency, Food and Drug Administration,
U.S. Department of Agriculture, National Association of People
With AIDS, AIDS Coalition to Unleash Power, and representatives
of state and local health departments and water utilities.
*CDC--Centers for Disease Control and Prevention
**EPA--Environmental Protection Agency
|
NEXT