Last Updated on January 3, 2019

When a water test comes back failed, it means that there is too much of a particular microorganism that could be harmful in the water and that it’s unsafe without proper treatment. Waterborne microorganisms, bacteria, virus, and protozoa can cause a range of health concerns from mild discomforts to severe neurological disorders, and in the most extreme cases, death. Everyone is susceptible to illnesses associated with failed water. Specific populations are at a higher risk, such as babies, infants, young children, pregnant women, elderly people, and those with compromised immune systems.
Top Bacteria, Protozoa, and Virus Causing Outbreaks in Well Water and Public Water

Bacteria, protozoa, and virus make up 5 of the top 6 outbreaks in private well water systems, and 10 of 11 outbreaks in public water.

Campylobacter – Bacteria
This bacteria can spread to the bloodstream and cause life-threatening infection particularly to individuals with weakened immune systems or blood disorders.

Cryptosporidium – Protozoa (also known as Crypto)
In healthy people, symptoms usually last 1 to 2 weeks but can come and go for up to 30 days. Those with weak immune systems can develop a chronic or fatal illness.

Escherichia coli, or E. coli – Bacteria
Most strains are harmless. However waterborne microorganisms such as, the Shiga toxin producing E. coli, or STEC, can cause gastrointestinal illnesses, urinary tract infections, and respiratory illness that may be mild or severe. Between 5-10% of those infected with STEC may develop Hemolytic Uremic Syndrome (HUS), a complication that may cause their kidneys to stop working.

Giardia – Protozoa that causes giardiasis
Extreme cases in children may cause physical and developmental delay and malnutrition.

Hepatitis A – Virus
A vaccine-preventable liver disease that can be transmitted through consumption of contaminated food or water. For adults, symptoms usually last for 2 months and include fatigue, low appetite, stomach pain, nausea, and jaundice. Most children less than 6 years of age do not have symptoms or have an unrecognized infection.

Legionella – Bacteria
This bacteria can cause two diseases: Legionnaires’ and Pontiac Fever. It was responsible for 57% of waterborne disease outbreaks reported to the CDC’s National Outbreak Reporting System during 2013-2014. While Legionnaires’ disease is a type of pneumonia, Pontiac Fever is not.

Norovirus – Virus
Highly contagious gastrointestinal virus.

Salmonella – Bacteria
Complications can include hospitalization for severe diarrhea, and risk of the infection spreading into the bloodstream.

Shigella – Bacteria that causes Shigellosis
Some people will have no symptoms but can pass the disease to others. High risk individuals may suffer a more extended illness duration. Individuals with a specific genetic makeup who become infected with a specific type of the bacteria called Shigella flexneri will experience post-infectious arthritis, which causes joint pains, eye irritation, and painful urination.
Ultraviolet Water Purification Systems Can Protect From Waterborne Microorganisms, Virus, Bacteria, and Protozoa
If your water test fails, installing an appropriately-sized Atlantic Ultraviolet water disinfection system will protect you from harmful microorganisms with little maintenance. Germicidal UV-C has been recognized for decades as a powerful, safe, rapid, and chemical-free water disinfection method and is listed by the CDC in “A Guide to Drinking Water Treatment Technologies for Household Use” as highly effective in eliminating waterborne microorganisms — bacteria (E. coli, Campylobacter, Salmonella, Shigella), protozoa (Cryptosporidium and Giardia), and virus (Enteric, Hepatitis A, Norovirus, Rotavirus).

Atlantic Ultraviolet’s UV-C water purification and disinfection systems use STER-L-RAY ® UV-C Lamps which are lethal to virtually all bacteria, protozoa, virus, and fungi. STER-L-RAY ® Germicidal Lamps are shortwave, low pressure tubes that produce ultraviolet wavelengths lethal to microorganisms. Approximately 95% of the ultraviolet energy emitted from STER-L-RAY ® germicidal lamps is at 254 nanometers, the region of germicidal effectiveness most destructive to bacteria, mold, and virus.
Learn More & Shop Our Products
Made or Assembled in the USA of high quality stainless steel, the UV water treatment systems from Atlantic Ultraviolet Corporation® are constructed of the highest quality materials and use germicidal UV-C lamps to purify water. Many applications can benefit from germicidal UV-C, including homes or facilities that have received a failed water test. For more information on UV-C water disinfection for failed water tests, visit our application-specific page.
Learn Here! Ultraviolet.com
- Learn about UV Water & Liquid Purifiers
- Download Ultraviolet Water Documents from our PDF Library
- Visit our Application-Specific Page: UV-C for Failed Water Tests
- View all the applications that can benefit from Germicidal UV-C
- Learn about STER-L-RAY ® Germicidal Ultraviolet Lamps
Shop Here! BuyUltraviolet.com
- Shop UV Water Purifiers for use When You Have a Failed Water Test
- Shop STER-L-RAY ® Germicidal UV Lamps
- Compare all models with our UV Water Purifier Comparison Chart
Need help? Call Our UV Specialists at 1-631-273-0500, Monday – Friday 7am to 6pm EST or fill out our contact form.

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View our infographic: Types of Waterborne Microorganisms that can Severely Affect Your Health
