Cryptosporidium is single-celled parasite that can contaminate water, soil, food that is uncooked, or be present in feces. There are actually several cryptosporidium varieties, though C. parvum tends to most often be responsible for intestinal infection in humans and animals. When any type of cryptosporidium is ingested, it tends to cause watery diarrhea that lasts for several weeks, usually resolving on its own.
This is not always the case. The very young, the elderly, and people with immune deficiencies caused by conditions like HIV are exceptionally vulnerable when they have ingested cryptosporidium. They can have extended bouts of the illness without treatment, and some people with undiagnosed cases can die due to excessive dehydration. Extensive dehydration can lead to organ failure and in infants, weight loss due to diarrhea can be significant, especially if at least 10% of body weight is lost in a short period of time.
There are a number of different ways in which one can come into contact with cryptosporidium. Though drinking liquids and eating contaminated food, or transferring the parasite from soil or feces to mouth are most common, swimming in water contaminated with the parasite can also cause infection if you swallow that water. Both animals and people can become infected, and if you have close contact with another infected person, especially touching their face or mouth, you can get the infection too if you don’t wash your hands. If pets have watery diarrhea lasting for more than a day, it’s a good idea to check with your vet to check for the presence of the parasite, since people can easily get this parasite from pets, particularly young pets.
Though infections of cryptosporidium are most common in developing countries, there have been numerous cases of it in highly developed countries. In the early 1990s, drinking water in Milwaukee, Wisconsin was found to contain the parasite. Over 400,000 people became seriously ill. Since then, infection with this parasite has been reported more often, though on average, in the US only about 3000 cases are reported each year. This amount may be higher and not reported, but Public Health officials do look for trends that might suggest contamination of a common food or water source.
Cryptosporidium infections create trouble, as there is no clear treatment in place. People who are healthy and who have strong immune systems often recover without treatment, but must be careful to drink plenty of liquids to replace lost fluids. Those who are not recovering or who have compromised immunity may take several medications, including anti-parasitic drugs, medications to help slow diarrhea, and anti-retroviral drugs which help increase immune response. This last is often used when people have HIV/AIDs. Other treatments may include fluid replacement, sometimes by intravenous lines, and several days of hospitalization if dehydration is severe.
Since a pound of cure can sometimes fail to be effective, an ounce of prevention is definitely preferable, especially if you have a compromised immune system. Careful handwashing should be observed at all times, and those with compromised immune systems should carefully weigh the risks versus benefits of swimming in non-chlorinated water. When traveling in foreign countries or when on vacation in the wild, filtering or purifying water is very important. You should also be extremely cautious when you handle farm or domestic animals, especially newborns. Wash hands thoroughly afterwards, and don’t accept licks or kisses from pets.