Is It Safe To Drink The Water?
On June 1, 1995, the Environmental Protection Agency (EPA) released some disturbing statistics: 53 million Americans drink water that violates U.S. safety standards. Yearly, contaminated water may cause the death of nearly 1000 people, and another 400,000 may contract a waterborne disease. An inescapable implication of these findings is that an individual who is immune-suppressed from HIV or cancer or as the result of a tissue or organ transplant is particularly vulnerable to waterborne infections. What does this information mean for an individual who is HIV-positive or has AIDS?
In a report released on June 15, 1995, federal health and environmental authorities suggested that people who are HIV-positive (or have weakened immune systems for other reasons) consider drinking only boiled, filtered, or bottled water. Why are the authorities concerned?
HIV-positive individuals are highly susceptible to the development of serious diseases, following infection with certain bacteria and parasites that take advantage of a weakened immune system. One such "opportunistic" parasite is Cryptosporidium, commonly referred to as "crypto," and it is of public concern.
Why does Cryptosporidium warrant special attention?
There are three reasons. First, it is hard to detect. Coliform counts to detect the intestinal bacteria that are harbingers of contaminated water are taken periodically to monitor municipal water systems; however, very few systems are tested specifically for Cryptosporidium. And crypto can lurk in water supplies that have been labeled safe as a result of acceptable coliform counts. Second, it is hard to get rid of crypto. Some large cities, such as Milwaukee, filter their water; others, such as New York, do not. Yet both cities have had outbreaks of crypto. Third, in a severely immune-suppressed patient, crypto is often untreatable.
How serious is the disease caused by Cryptosporidium?
The ability of crypto to cause disease depends on several factors, including the number of infectious parasites to which a person is exposed and, especially, the status of that person's immune system. The common symptoms of nausea, stomach cramps, and diarrhea are short-lived and self-limiting in a healthy person. But when immunity has been weakened, antibiotics are needed to arrest the disease. A long-term response to currently available antibiotics, however, usually occurs only when the CD4+ T cell count is over 150. Below 150, the case may be chronic, with severe diarrhea requiring lifelong drug therapy that has only limited effectiveness.
Is Cryptosporidium the only waterborne infection that should be of concern?
No. There are other serious diseases that are caused by similarly transmitted parasites, such as Isospora and Cyclospora. But they are relatively easy to treat with common antibiotics.
Can I protect myself by drinking only bottled water?
Probably not. First, it is very rare that an individual can avoid all contact with tap water, even though treated water is used during dental hygiene and similar activities. Second, many brands of bottled water actually contain tap or spring water that, in fact, harbors crypto.
What about filtering all my water?
Surprisingly, there are no federal standards related to the effectiveness of water filters in blocking crypto and related organisms. Products that employ reverse osmosis or those certified by NSF International appear to be reliable, but they are expensive to purchase initially and to keep supplied with replacement filters.
How about boiling water?
Bringing water to a rolling boil for one full minute is the only completely effective method for eliminating crypto. The water should be stored in the refrigerator in capped bottles that have themselves been sterilized in boiling water.
Will boiling all my drinking water eliminate Cryptosporidium as a threat to my health?
Unfortunately, no. There are several other sources, including foods (unpasteurized apple cider recently caused an outbreak in Maine); sex involving fecal contact; and water swallowed while swimming in a contaminated pool. Moreover, an adult, particularly a sexually active one, already may be "colonized" with crypto that is, may harbor the parasite in an inactive form and, as that person's immune defenses decline, the parasite may begin to grow and subsequently cause disease.
That's all very interesting. But what should I do?
Let me first outline what two national authorities have suggested; then I'll give you my own opinion. The American Water Works Association has stated that "people infected with HIV should always boil water to kill any Cryptosporidium." The EPA has stated that "current risk data are not adequate to support a recommendation that severely immunocompromised persons in all U.S. cities boil or avoid drinking tap water."
People with AIDS are in the confusing position of having to make decisions in an area of ongoing scientific controversy. National authorities have given conflicting opinions as to the need to boil or filter tap water. In this setting, each individual should have access to all information available, in order to make an informed decision. I now offer my own recommendation as a physician and AIDS researcher.
My belief, based on small pilot studies, is that most HIV-positive adults are probably colonized with Cryptosporidium already. Thus, unless a specific outbreak of crypto is reported in your area, boiling water religiously and avoiding contact with all other water sources (swimming pools, etc.) may not be appropriate. At present, there is not enough evidence to justify adding yet another health concern to the multitude of more pressing concerns that confront most HIV-positive individuals. But if you decide to limit the likelihood that crypto will enter your body from the water you drink, then the one minute boil is appropriate.
This article was provided by amfAR, The Foundation for AIDS Research. Visit amfAR's website to find out more about their activities and publications.