Serratia marcescens is a rare opportunistic bacterium that is categorized in the enterobateriaceae family commonly found in the environment. The bacteria can produce prodigiosin, a pigment color that ranges from lights pink to dark red. The color can identify the age of the bacterial colony which thrives in the soil, water, and the digestive tract of many mammals, including humans.
Most of us have seen Serratia marcescens in our daily environment when colonies of the bacteria appear in the toilet bowl, shower stall, bathtub, or the pet's water dish as a pink film. In addition to appearing on water surfaces, it is also found in dust in the feces of animals and humans. The bacteria can become airborne from numerous sources that occur naturally. In recent years, the bacteria have become a problem in many households that use activated carbon filters to remove chlorine added to the water supply.
The toilets in the home that are used less often, like in the guest bathroom, can be the ideal breeding ground for Serratia marcescens where standing water allows the chlorine to dissipate. Many water companies in the United States will add a minimal amount of chlorine to ensure the drinking water is disinfected and safely consumed, free of Serratia marcescens. However, allowing the water to stand for 30 minutes or more can cause the chlorine disinfectant to evaporate into the atmosphere.
- Who Is at Risk for Serratia Marcescens?
- How to Minimize Risks
- Serratia Marcescens Treatments
- Proven Infection Control Measures
Who Is at Risk for Serratia Marcescens?
Serratia marcescens was once considered to be an innocuous water organism. However, scientist now knows that the bacteria can be a significant problem when reservoirs of Serratia marcescens are found in the respiratory tract, digestive tract, and urinary tract in humans. Healthcare workers and individuals who wear artificial nails are also at risk of exposure to Serratia marcescens. Intensive care units (ICUs) at hospitals can develop epidemics of infection from the colonization of Serratia marcescens where the bacteria is found in medical equipment, drugs, blood products, antiseptics, lotions, showers, toilets, and sinks.
Individuals at greatest risk of those that develop a nosocomial (hospital-originating) infection that is confined to soft tissue, surgical wounds, the urinary tract, or respiratory tract. While the condition is rare, exposure to Serratia marcescens could lead to meningitis, especially in pediatric wards at medical centers and hospitals. Other individuals at risk of harm caused by the bacteria include:
- Heroin Addicts – Serratia marcescens is known to cause osteomyelitis and endocarditis in heroin addicts.
- UTI Sufferers – Hospital patients who develop urinary tract infections (UTIs) are usually asymptomatic, meaning they have no symptoms of the disease or owners.
Nosocomial bloodstream infections, including Serratia marcescens, often result in a high mortality rate, especially if the patient develops endocarditis or meningitis that are known to because by the bacteria. However, there are at least 14 distinct strains of Serratia marcescens, some of which are highly resistant antibiotics.
Another risk factor associated with Serratia marcescens includes the placement of IV (intravenous) catheters, urinary catheters, and intraperitoneal catheters. Patients with wound infections or those who develop pneumonia while in a hospital setting are also at risk for developing a severe Serratia marcescens infection.
One study revealed that the spread of Serratia marcescens was prominent in hospital settings amongst facility personnel through hand-to-hand transmission where 50% of hand cultures from the medical team tested positive when samples were obtained at the end of the working shift.
How to Minimize Risks
Once the bacteria have established an environment they usually cannot be entirely eliminated. Hospitals and households should perform periodic thorough cleaning of every surface that develops the pink slime. This cleaning process should be followed by intensive disinfection procedures using a chlorinated product like bleach to ensure the organism's control.
The best way to minimize the potential risk of suffering harm from Serratia marcescens include:
- Thorough Cleaning – A thorough cleaning of all kitchen and bathroom surfaces along with the pet's water bowl is necessary by scrubbing the surface where any fatty or phosphorus substances have accumulated. The bacteria can be destroyed using household cleansers with a brush.
- Disinfecting Surfaces – A thorough disinfection of any surface where the pink slime has developed using a solution of strong chlorine bleach products.
- Thorough Rinsing – Allow the disinfecting solution to remain on the affected surface for a minimum of 20 minutes before the area is thoroughly rinsed using clean water.
- Do Not Scratch the Surface – Take precautions to avoid scratching the surface with an abrasive that conform deep crevices making the surface highly susceptible to the growth of bacteria in hard to reach places.
- Use Chlorine Bleach Spray – Toilet bowls are highly susceptible to accumulating the hazardous and dangerous pink slime and should be thoroughly cleaned followed by a chlorine bleach spray on the bowl's interior and under the room. Allow the bleach to remain in the water for a minimum of 20 minutes before flushing the bowl.
When the surface of the toilet bowl begins to develop a film of pink slime, it's time to repeat the cleaning process followed by a thorough disinfection of the area. However, it is important to note the cleaning the services are flushing the bowl using chlorinated products will never eliminate the presence of Serratia marcescens completely. However, taking the appropriate steps listed above can control and manage the bacteria.
Serratia Marcescens Treatments
The deadly bacterium is inherently resistant to most common narrow-spectrum penicillin medications. This includes amoxicillin, ampicillin, ampicillin-sulbactam, amoxicillin-clavulanate and numerous cephalosporins. Because of that, over the last four decades, the bacterium has become a severe health care-associated pathogen that revealed its multiple antimicrobial resistant properties.
That said, many hospitals never experience problems associated with Serratia marcescens when identified, take appropriate measures to readily treat those affected. However, other hospital settings are highly susceptible to cross infections due to a lack of following disinfecting procedures in the healthcare population.
Research shows that infection outbreaks usually coincide with the breakdown of hospital procedures to control infections. It is in the settings at the pathogen continues to thrive in the hospital causing it to become highly resistant to any treatment.
Proven Infection Control Measures
Due to the high susceptibility of some hospital environments failure to control Serratia marcescens infections, certain preventative measures can be highly effective. This includes developing, implementing, and enforcing proven infection control policies especially where infections involving Serratia marcescens are evident and/or have been isolated.
This includes isolating multi-resistant strains of the bacteria, implementing strict and hygiene policies and identifying and isolating the organism through a microbiology laboratory analysis before choosing the appropriate therapy to control the infection throughout the hospital population.
Because the majority of Serratia marcescens infections are the result of hospital personnel negligence, patients who develop an infection have legal rights to seek financial recovery for their damages, losses and injury. This is because the hospital should have developed and enforced defective policies that minimize exposure to the dangerous bacterium by sanitizing surfaces, promoting hand hygiene and enforcing equipment/fixture disinfecting policies to minimize every patient's risk of being injured by contaminated surfaces.