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What’s in Your Tap Water? Legionnaires’ Disease Linked to Most Tap Water Outbreaks.

Posted in Legionnaire's disease,Our Blog on March 27, 2024

A recent study looking at drinking or tap water outbreaks found some startling facts. Legionnaires’ disease was linked to most tap water outbreaks. Turns out, biofilms may be the largest contributing factor.

Waterborne and Tap Water Outbreaks

Waterborne pathogens are responsible for an estimated 7.15 million illnesses in the United States each year. This accounts for around 118,000 hospitalizations and 6,630 deaths annually. Health care costs for these illnesses come to upwards of $3.33 billion.

That is billion, with a “B.”

According to reports, drinking water accounts for 40% of those hospitalizations.

Biofilm pathogens, such as Legionella and nontuberculous mycobacteria account for 50% of those deaths, racking up a bill of $1.39 billion annually. All from a product delivered at the turn of a faucet in your home.

The Study

This study analyzed data from 2015 to 2020. Public health officials from 28 states submitted their historical data during that time period.

There were 214 tap water outbreaks included in this study. Outbreak data indicated that 187 of the outbreaks were associated with biofilm pathogens. Coming in second were enteric illnesses (caused by other bacteria, viruses, and/or parasites). There were also two of unknown cause and one outbreak associated with a chemical or toxin.

Most of these outbreaks were linked to public water systems. Meaning tap water. The rest were associated with unknown water systems, individual or private water systems, and coming up the rear were other types of water sources (accounting for just over 1%).

Tap Water Outbreaks

Tap water outbreaks were responsible for at least 2,140 cases of illness with 26% (263 patients) requiring hospitalizations. These outbreaks resulted in 88 deaths linked to tap water.

Tap water outbreaks were responsible for at least 2,140 cases of illness with 263 patients requiring hospitalization and 88 deaths

Individual or private water systems (such as wells, cisterns, and larger private water systems serving more than one residence) were linked to 944 cases, 52 hospitalizations, and 14 deaths.

Legionella-associated outbreaks (Legionnaires’ disease) were linked to 786 cases of illness with 544 hospitalizations and 86 deaths across all water sources. Among tap water outbreaks associated with public water systems, Legionella bacteria was responsible for 92% of them with 160 cases.

The greatest contributing factors discovered in waterborne outbreaks is Legionella bacteria and tap water or other biofilm associated pathogens.

The greatest contributing factors discovered in waterborne outbreaks is Legionella bacteria and tap water

This leads researchers to focus mostly on biofilm pathogens and how they contaminated tap water.

What are Biofilms?

Biofilms are “microbial communities.” They like moist surfaces, like those of water pipes, and serve as a sort of protection and even provide nutrients for different types of bacteria, such as Legionella.

Biofilms can form when water becomes stagnant or when disinfectant activities are ineffective, allowing pathogens to grow.

Once formed, biofilm is difficult to control. They are highly resistant to many water treatment practices and hold up to many disinfection practices. When it forms, serious remediation may be necessary to eliminate the risk of biofilm pathogens.

These biofilm pathogens can cause infection through contact, ingestion, or even aerosol inhalation (as is the case with Legionella bacteria).

How is Legionella Bacteria Transmitted in Tap Water Outbreaks?

Unlike some bacterial infections, Legionella bacterial infection (known as Legionnaires’ disease) is not transmitted through consuming water or contact with it. People become infected with Legionella bacteria by breathing in aerosols.

Legionnaires’ disease is caused by inhaling Legionella bacteria through contaminated water droplets aerosolized in the air

Common Legionella reservoirs include:

  • Hot tubs
  • Hot water tanks and heaters
  • Large, complex plumbing systems
  • Showerheads and sink faucets
  • Decorative fountains and water features
  • Cooling towers (structures that contain water and a fan as part of centralized air-cooling systems for buildings or industrial purposes

These types of fixtures either allow for the formation of biofilm, promoting Legionella bacterial growth, or create aerosols that propel the bacteria to their next unknowing host.

Legionnaires’ Disease Symptoms

Symptoms of Legionella infection or Legionnaires’ disease are often confused with other types of pneumonia illness. In fact, without specific diagnostic tests it is often undiagnosed.

Common symptoms include typical pneumonia symptoms such as acute onset of lower respiratory illness with fever and/or cough.

Other symptoms may include:

  • Muscle aches/pain
  • Shortness of breath
  • Headache
  • Malaise
  • Chest discomfort
  • Confusion
  • Nausea
  • Diarrhea
  • Abdominal pain

Legionnaires’ disease is treated with a specialized antibiotic protocol. Those who are improperly diagnosed and treated for general pneumonia may recover, but not as quickly as they would have with proper treatment.

If you have these symptoms and have been exposed to any of the “common Legionella reservoirs” listed above, notify your healthcare provider so that Legionnaires’ disease can be ruled out.

Other Types of Tap Water Outbreak Pathogens

While Legionella is the most common and prevalent waterborne pathogen associated with tap water outbreaks, there are others.

Campylobacter, Escherichia coli (E. coli), Giardia, norovirus, Shigella, and others are included as “other enteric illnesses” in the study findings.

Other enteric pathogens include Campylobacter, E. coli, Giardia, norovirus, and Shigella

These pathogens were responsible for a collective 1,299 cases of illness, 10 hospitalizations, and no deaths.

Have You Become Sick from a Tap Water Outbreak and Need Help?

If you have become sick with Legionnaires’ disease from a tap water outbreak and want to know your options, consider contacting a Legionnaires’ disease lawyer.

The experienced Legionnaires’ disease lawyers at The Lange Law Firm, PLLC have represented many families with Legionnaires’ disease cases. Their knowledgeable team has recovered millions of dollars to help families and hold those responsible accountable for their actions.

Call (833) 330-3663 or email here for a free consultation.

Want to Know More About Water Safety?

If you’d like to know more about water safety in the news, like “What’s in Your Tap Water?”, check out the Make Food Safe Blog. We regularly update trending topics, foodborne infections in the news, recalls, and more! Stay tuned for quality information to help keep your family safe, while The Lange Law Firm, PLLC strives to Make Food Safe!

By: Heather Van Tassell (contributing writer, non-lawyer)