Which organism is known to cause illnesses and is particularly resistant to disinfection methods?

The organism known to cause illnesses and particularly resistant to disinfection methods is Cryptosporidium. This microorganism is a protozoan parasite that can lead to gastrointestinal illnesses, known as cryptosporidiosis, characterized by diarrhea, abdominal cramps, and vomiting.

One of the critical challenges associated with Cryptosporidium is its robust oocyst form, which is highly resistant to common disinfection methods used in water treatment, such as chlorine. Consequently, while treatment processes may effectively reduce other contaminants, they may not adequately eliminate Cryptosporidium, leading to potential outbreaks and health risks if the water supply becomes contaminated.

Understanding the resistance of Cryptosporidium underscores the need for specific treatment interventions, such as filtration or advanced oxidation processes, to ensure safe drinking water. This highlights why awareness and monitoring of such resistant organisms are vital in the field of water treatment and public health.