Additional Information on Prevention Cryptosporidiosis

Additional Information on Prevention Cryptosporidiosis for Persons Who are Immunocompromised

Do the precautions listed for persons with healthy immune systems apply to me?

If you are HIV positive or otherwise immunocompromised, you should adhere strictly to the preventive measures suggested for persons with healthy immune systems. Be extra careful about what you eat and drink. Be careful not to let raw foods contaminate other foods. Be a fanatic about hand washing, including after touching animals. Avoid accidentally swallowing water from lakes, rivers or swimming pools.

What about my drinking water?

Current data are inadequate to recommend that all immunocompromised persons boil or avoid drinking tap water in non-outbreak settings. However, you may want to discuss the need for taking further protective measures with your medical provider because:

• Drinking water that is considered safe for persons with healthy immune systems may contain some Cryptosporidium oocysts;
• No one knows whether a few oocysts could create a risk for someone who is immunocompromised;
• Some researchers think that oocysts ingested while you are still relatively healthy may remain in your gallbladder until your immune system is severely depressed and then cause serious illness.

What are some options for safer beverages?

1. Bring tap water to a full boil for one minute before using.

• This will kill all organisms including Cryptosporidium.
• To avoid burning yourself, allow water to cool before pouring into clean, dry containers.
• Taste can be improved by adding lemon or other flavorings.
• Use the boiled water for ice cubes, toothbrushing and mixing with concentrates. You don't need to use boiled water for food that will be cooked before eating.
• Dishes, silverware, pots and pans may be washed with tap water as long as they are dry before being used.

2. Use a point-of-use (personal-use, end-of-tap, under sink) filter that will remove particles one micron or less in diameter.

• Filters in this category include:

• those that produce water by reverse osmosis,
• those labeled as "Absolute" one micron filters, and
• those labeled as meeting NSF (National Sanitation Foundation) standard #53 for "Cyst Removal".

• The "Nominal" one micron filter rating is not standardized. Therefore, filters in this category may not be as good at removing oocysts.
• Be sure to accurately follow directions for filter use and replacement.

3. Use bottled water.

• Be careful, because bottled water doesn't have to meet the same standards as water coming from a treatment plant.
• If you can verify with the manufacturer that the water has been passed through filters capable of removing particles one micron or less in diameter or has undergone reverse osmosis prior to bottling, then it has been treated for the removal of Cryptosporidium oocysts.

4. Use distilled water, commercially bottled soft drinks and seltzers. Bottled juices are safe if they have been pasteurized and do not require refrigeration before opening.

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