The 1987 Carroll County cryptosporidiosis outbreak was a significant distribution of the Cryptosporidium protozoan in Carroll County, Georgia.[1] Between January 12 and February 7, 1987, approximately 13,000 of the 65,000 residents of the county suffered intestinal illness caused by the Cryptosporidium parasite.[2] Cryptosporidiosis is characterized by watery diarrhea, stomach cramps or pain, dehydration, nausea, vomiting and fever.[3] Symptoms typically last for 1–4 weeks in immunocompetent individuals.[4]
The parasite was found to have been transmitted through the public water supply.[5] State health authorities were first alerted to the situation by Mary R. Miles, a health center physician at the University of West Georgia in Carrollton, Georgia.[1]
A subsequent investigation by the Centers for Disease Control and Prevention (CDC) confirmed the presence of Cryptosporidium in water samples taken from the municipal water system on January 28, February 4 and February 5. Edward B. Hayes, the lead epidemiologist from CDC, was unable to pinpoint the source of the contamination but "suspected" it was either "infected cattle bathing in a river" that supplied Carrollton's water or a sewage spill later discovered near the municipal water treatment plant.[2]
Dennis D. Juranek, also an epidemiologist at the CDC, observed that the treatment plant had at all times met the safe-water standards set by the Environmental Protection Agency (EPA) and questioned whether the standards were "tough enough to ensure that treatment plants snare passing microorganisms." Juranek said: "The Carrollton outbreak would seem to point out that if you're just meeting [EPA] standards, it's probably not adequate."[2]
It is believed that removal of mechanical agitators at the flocculation stage resulted in the passage of particulates.[6]