An immunocompetent person is infected with Cryptosporidium and developed diarrhea with abdominal cramps. All of the following are TRUE about Cryptosporidium, EXCEPT:

Oocysts measuring 4-5 m are passed in feces in enormous numbers and are immediately infectious. Oocysts shed into the intestinal lumen mature to contain four sporozoites; their cell wall provides the unusual propey of acid-fastness, allowing them to be visualized with stains generally employed for mycobacteria. EIA tests are now available for detection of fecal antigen. Prevention of Cryptosporidium infection is limited by oocyst resistance to some of the standard water purification procedures (chlorination) and to common disinfectants. Ref: Brooks G.F., Carroll K.C., Butel J.S., Morse S.A., Mietzneron T.A. (2010). Chapter 46. Medical Parasitology. In G.F. Brooks, K.C. Carroll, J.S. Butel, S.A. Morse, T.A. Mietzneron (Eds), Jawetz, Melnick, & Adelberg's Medical Microbiology, 25e.