Legionella
Legionella is a bacteria found in both potable and nonpotable water systems that proliferates rapidly in warm water environments. Legionnaires' disease, the resulting condition of being affected by Legionella, is a severe, often lethal, form of pneumonia that affects up to an estimated 18,000 people in the United States each year.
Pseudomonas
Pseudomonas aeruginosa is an opportunistic pathogen commonly found in moist environments and plumbing systems that is a common source of infection such as pneumonia, urinary tract infections, sepsis, and multiple other ailments.
Mycobacteria
Mycobacteria is a bacteria found in water systems that is the cause of Nontuberculous Mycobacteria (NTM) disease as well as several other ailments. It proliferates rapidly in warm water environments and poses a threat when exposed to humans.
Stenotrophomonas
Stenotrophomonas maltophilia is a bacteria found in moist environments and plumbing systems and is the cause of a wide range of illnesses such as bacteremia, pulmonary infections, urinary tract infections, meningitis, and many others.
Cryptosporidium
Cryptosporidium, also known as "Crypto" is a bacteria found in water systems that is the cause of cryptosporidiosis as well as several other ailments. It is very resistant to chlorine, which is why it can survive for days even in properly chlorinated pools.
Giardia
Giardia lamblia is a waterborne parasite that lives in the intestine of infected humans or animals. You can become infected after accidentally swallowing the parasite or via contact with blood. Giardia have been proven to be extremely resistant to oxidant treatments such as chlorine.