Serratia is a type of bacterium commonly found in various natural environments. Serratia marcescens is a species of rod-shaped, Gram-negative bacteria belonging to the Enterobacteriaceae family. These microorganisms are widespread and can adapt to many different habitats.
Understanding Serratia
Serratia marcescens is found in soil, water, plants, and insects. It thrives in damp environments, commonly appearing in bathrooms on tile grout, shower corners, and toilet water lines. This bacterium feeds on phosphorus-containing materials or fatty substances, such as soap and shampoo residues, which accumulate in moist areas.
A distinctive characteristic of Serratia marcescens is its ability to produce a reddish-orange pigment called prodigiosin. This pigment causes the pink, pink-orange, or orange discoloration often mistaken for “pink mold” or slime in damp household areas. Not all strains produce this pigment. Optimal conditions for prodigiosin production include temperatures around 22–32 °C.
Serratia and Human Health
While Serratia marcescens is prevalent, it is primarily an opportunistic pathogen, causing infections particularly in individuals with compromised defenses. It is a cause of hospital-acquired infections. Such infections disproportionately affect people with weakened immune systems, those in intensive care units, or individuals undergoing invasive medical procedures.
Serratia marcescens can lead to various infections, including urinary tract infections, respiratory tract infections like pneumonia, and wound infections. It can also cause bloodstream infections, which are common in hospitalized patients. Less frequently, it may be associated with meningitis or endocarditis, particularly in specific patient populations.
Transmission of Serratia marcescens often occurs through direct contact with contaminated surfaces or infected individuals. In healthcare settings, contaminated medical equipment, such as catheters or respiratory therapy devices, can serve as sources of infection. Contamination of healthcare professionals’ hands is also a primary way the infection spreads within clinical environments.
Preventing and Addressing Serratia
Controlling the growth of Serratia marcescens in household environments involves consistent cleaning and maintenance. Regularly scrubbing damp areas like sinks, showers, and toilets with a brush and household cleanser helps remove the bacteria and its food sources. Disinfecting these surfaces with a chlorine bleach solution, allowing it to sit for 10 to 20 minutes before rinsing, is effective in controlling the slime.
Maintaining dry surfaces after use and ensuring proper ventilation in bathrooms significantly reduces moisture, making the environment less hospitable for bacterial growth. Wiping down shower walls with a squeegee or towel after each use and using exhaust fans during and after showers helps prevent moisture accumulation. Regular hand-washing also helps prevent the transfer of bacteria to other surfaces.
In healthcare settings, rigorous sanitation and infection control measures are important to curb the spread of Serratia marcescens. These measures involve strict hygiene protocols for staff and thorough disinfection of medical equipment and patient environments. If a Serratia infection is suspected, particularly in individuals with underlying health conditions or those who have been hospitalized, seeking prompt medical attention is advisable. Diagnosis of Serratia infections involves laboratory testing, and treatment often includes specific antibiotics tailored to the particular strain and infection site.