As a fellow of ACOG (The American College of Obstetricians and Gynecologist, the term “fellow” has no gender significance)….I recently received a survey to complete with questions about my age, number of hours I teach, see patients, percent of patients who are on Medicare, languages I speak, etc….the usual questions that one would expect them to ask in order to keep their census up to date. But this time they included a second page of questions that asked about my knowledge of a specific infection. When I realized my knowledge was minimal (actually I didn’t know anything about it), I quickly looked it up so that I could mark their queries in other than the column “I don’t know”. (The survey was multiple choice).

I’d like to share the information I learned with you….not because you too will be “tested” but because general knowledge about this water borne infection in not well known (even by doctors) and there are warnings that should be issued to help protect many of us.

The infection is due to a parasite called Cryptosporidium. It causes (you guessed it) cryptosporidiosis (nick name Crypto) …which usually manifests itself as diarrhea. It’s a fascinating organism. It thrives in cattle, sheep and pigs as well as wild animals such as deer, elk and moose, especially their young offspring (calves and lamb) and, unfortunately, in humans. Once a parasite gets to the small intestine (the gut) though ingestion, it can multiply and recycle indefinitely. In a fascinating process, once in the gut, this microscopic parasite actually undergoes a sort of fertilization to form a zygote, and this ends up having 4 offspring called sporozoites. (Sorry if I am getting too detailed, but it’s the biologist in me.) Some sporozoites remain in the gut and infect new cells. Others that get surrounded by a cyst wall become oocysts, and these are passed in the feces and into the environment. All this happens astoundingly quickly…each generation can develop and mature in 12 to 14 hours. During the last 2 decades, “Crypto” has become one of the most common causes of waterborne disease in humans in the US and through out the world!

The usual source of infection is water that has been contaminated by the feces of animals or infected humans. If a person drinks the water or involuntarily swallows it while swimming, they then “catch” cryptosporidiosis. Crypto has been found in swimming pools, hot tubs, Jacuzzis, fountains, lakes, springs, rivers, and ponds which can be contaminated with sewage or feces from humans or animals. It can be spread by eating uncooked food that is contaminated, by touching your mouth with contaminated hands…which could have “picked up” the parasite from touching surfaces (and this includes diapers) that have been contaminated by stool from an infected person or handling an infected cow or calf. (We do the latter infrequently in LA.)

Symptoms of the infection usually appear within 2 to 10 days of exposure and include diarrhea, abdominal cramping, nausea, vomiting, low grade fever and weight loss. In persons who are immunocompromised (due to diseases such as AIDS or cancer), the infection may become life threatening. The good news is that the immune system in healthy individuals is able to stop the infection, although symptoms may last for one to two weeks. But even after symptoms subside, sporozoites can be excreted in the feces and if that person swims, he or she can pass them into the water from spores that are present in the outer part of the anus or even on the thighs (ugh!). Here is where physician advice should include sanitary precautions to wash hands, use separate towels and not go swimming for 2 weeks after all the symptoms have resolved. The other rather concerning information that I discovered was that chlorine disinfection of the organism is ineffective; even one oocyst can withstand pure bleach for 24 hours and still cause infection .Most water filters today do remove small particles including cryptosporidium from our drinking water…but this may not occur in home wells (or swimming pools).

According to the CDC, the best way to protect yourself and others from this cause of diarrhea is to:

• Wash your hands after using the toilet and before handling food (especially for persons with diarrhea).
• Wash hands after every diaper change, especially if you work with diaper-aged children.
• Do not swim if you are experiencing diarrhea (essential for children in diapers) and stop for 2 weeks after diarrhea subsides
• Avoid water that might be contaminated.
• Do not swallow recreational water.
• Do not drink untreated water from shallow wells (or boil it first).
• Do not consume untreated ice or drinking water when traveling in countries where the water supply may not be safe.
• Use safe uncontaminated water to wash all food that is to be eaten raw (and if there is a chance that the food might be contaminated, peel it).
• Avoid eating uncooked foods while traveling in countries with poor water treatment and food sanitation
• You’ll love this one….avoid fecal exposure during sexual activity.

The diagnosis can only be made if stool samples are tested for the parasite, and frankly the test is not always positive the first time so several samples may be necessary.

The only FDA approved treatment is through a prescription of a medication called nitazoxanide (brand name Alinia). Most people with healthy immune systems will recover without treatment. Diarrhea should be managed with fluids to prevent dehydration.

So now you know and could “pass” the survey put out by ACOG. If I include a bottom line, as I usually do in my newsletter, it would probably include the phrase “Don’t swallow” (at least while swimming), know your drinking water source and wash your hands!