Preventing Cryptosporidiosis : Part 3

by CDC

(Page 3 of 3)

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: [phone], fax: [phone]), 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 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:

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.

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.

About the Author

www.cdc.gov
The Centers for Disease Control and Prevention (CDC) is one of the 13 major operating components of the Department of Health and Human Services (HHS), which is the principal agency in the United States government for protecting the health and safety of all Americans and for providing essential human services, especially for those people who are least able to help themselves.