Biofilm buildup in your water pipes
Pseudomonas aeruginosa, a bacteria that—like Legionella —lives in water pipes as biofilm builds up, can be deadly for immunocompromised patients.
The deaths of two premature infants at Miami Children’s Hospital illustrates the risk, although in that case, the source of the Pseudomonas (pronounced soo-duh-MOAN-us) is unclear.
What is more certain is that hospitals can’t count on chlorine piped into local water supplies to wipe out Pseudomonas because the bacteria can resist the chemical, says Matthew Freije, president of HC Information Sources, Inc., a waterborne pathogens consulting company in Carlsbad, CA.
Freije advises all medical centers to set up water monitoring and maintenance programs to avoid potential problems.
“Pseudomonas outbreaks happen more often than what is realized,” he says.
Note these hospital responses
The situation at Miami Children’s Hospital is murky. Although the two infants died there in March and investigators from the Miami-Dade County Health Department found several strains of Pseudomonas in the neonatal ICU, sample results didn’t provide a match to the strain that infected the infants.
However, based on the presence of other Pseudomonas strains in the NICU, investigators made several recommendations that the hospital has since taken or plans to take, according to a county environmental health report. Those steps include:
- Replacing sink plumbing and fixtures in certain NICU rooms
- Superchlorinating the hospital’s water, which involves adding extremely high doses of chlorine
- Setting up a water monitoring program
- Participating with the county in annual chlorine purges of the water system
Be careful about drawing conclusions
At a press conference with lead investigator Vincent Conte, local reporters asked whether the deadly bacteria that killed the infants came from another hospital where they were born, a helicopter that brought them to Miami Children’s Hospital, or Miami Children’s itself.
‘‘It had to come from one of the three,’’ Conte said, as quoted by the Miami Herald. “But since we have no environmental matches, we can’t say it came from point A, B, or C.’’
The Florida Agency for Health Care Administration will be overseeing Miami Children’s Hospital’s compliance with health department recommendations. State regulators can fine the hospital $1,000 per day for each violation it finds and suspend or revoke the facility’s license. At presstime in mid-July, Miami Children’s Hospital had not provided Briefings on Hospital Safety with more information about the incident or actions it had taken in reaction to the Pseudomonas discovery.
However, a hospital spokesperson told the Miami Herald the hospital will cooperate with the health department’s recommendations.
Check your water systems
Forward-thinking hospitals should perform or contract for an assessment of their plumbing systems for the presence of Pseudomonas and other problematic bacteria, Freije says.
Such assessments should focus not only on the water, but also cooling towers, hydrotherapy pools, and everywhere else water flows. Doing it before a potential outbreak helps establish baseline measurements for monitoring.
From there, hospitals can write a water management plan that covers design, construction, operation, and maintenance of their water systems to minimize disease risk.
A plan should include means to avoid water stagnation and the biofilm buildup that can come with it, sometimes utilizing valves and pipe flushing.
“Most hospitals have no idea how many hospital-acquired infections they have, let alone how many are caused by water or are water-related,” Freije says. “Once we have more data on that, I think it will be eye-opening.”
You might also be surprised about the chlorine levels in the municipal water coming into your facility, he says. Many hospitals lose the chlorine—or find it greatly reduced from its point of entry in the facility—in cold water running through the building pipes. It’s almost always eliminated in the hot water once it goes through heating systems.
Under EC.02.05.01, element of performance 5, The Joint Commission (formerly JCAHO) requires hospitals to minimize the presence of pathogens in domestic water systems, cooling towers, and other aerosolizing water systems. The provision falls under the requirements for utility system management.
Prevent biofilm accumulation
Samir Elmir, director of the Miami-Dade County Health Department’s environmental health and engineering division and an investigator of the Miami Children’s Hospital deaths, offers the following general recommendations for maintaining safe water quality in hospital plumbing:
- Create on-site water main flushing procedures and identify all dead ends within the plumbing system. This prevents water stagnation, ensures effective maintenance of disinfectant residuals, and prevents biofilm buildup.
- Establish a backflow prevention program, including all plumbing systems (e.g., sprinkler lines, irrigation, and domestic water lines). Conduct routine checks, including visual inspections, and respond to complaints.
- Routinely monitor and record residual chlorine levels inside your buildings, emphasizing areas with low water use, critical care areas, and meters. Make sure chlorine levels in the plumbing system are equal to the levels provided by the water system.
- Conduct monthly standard heterotrophic plate count (HPC) analysis throughout the water plumbing system. Although no enforceable standard currently exists for HPC, the Environmental Protection Agency sets acceptable HPC levels in drinking water at less than 500 colony-forming units per milliliter. HPC analysis is a good tool for monitoring water quality, especially when performed regularly. This will yield trend data and establish a baseline count. Deviations from baseline numbers warrant investigation.
- Provide training to engineering and plumbing staff members using the Centers for Disease Control and Prevention’s Guidelines for Environmental Infection Control in Healthcare Facilities as a reference (go to www.cdc.gov and search for the term “environmental infection control”).
- Consider an active supplemental disinfection of the hospital potable water systems, such as with chlorine dioxide, which is a powerful chemical compound that is less corrosive than regular chlorine in water applications. This provides added protection against biofilm buildup and opportunistic waterborne pathogens that can take up residence in it.
One way to distinguish Pseudomonas from Legionella
From an infection control standpoint, a big difference between Pseudomonas and Legionella is that Pseudomonas can live outside of water, making it tough to investigate and pin down the source of infection.
“Legionella is entirely environmental. You know it’s coming from the water,” says Matthew Freije, president of HC Information Sources, Inc., a waterborne pathogens consulting company in Carlsbad, CA. “Pseudomonas is a little trickier because a patient can actually contaminate the surface of a faucet and give it to another patient or a healthcare worker.”