Methicillin-resistant Staphylococcus aureus, commonly known as MRSA, is a type of staph infection that has developed resistance to several widely used antibiotics, including methicillin, amoxicillin, and penicillin. This resistance makes MRSA infections more challenging to treat compared to typical staph infections. MRSA bacteria can be found in various environments, including on surfaces, and understanding its survival outside the human body is important for public health awareness and prevention.
How Long MRSA Lives on Surfaces
MRSA bacteria can persist on inanimate surfaces for varying periods, often ranging from days to weeks, and in some cases, even months. Studies show MRSA can survive for up to 7 months on dust, 8 weeks on a mop head, and 9 weeks on a cotton towel. It can also live for over 6 months on a blanket. On hard surfaces like countertops and toilets, MRSA can survive for days or weeks. This extended survival outside a host contributes to its potential for transmission.
The exact duration of MRSA survival on surfaces is not fixed, as it depends on environmental conditions. While it can persist for long periods, its ability to cause infection may decrease over time. This highlights the importance of consistent cleaning practices to minimize transmission risk.
What Affects MRSA Survival
Several environmental factors influence how long MRSA can survive on surfaces. Temperature plays a role, with colder conditions generally prolonging the bacteria’s viability.
Humidity and moisture levels also affect survival. Drier conditions can sometimes reduce the lifespan of bacteria, but certain strains can persist even in low-moisture environments. The type of surface material also matters, as porous materials like fabrics (e.g., towels, clothing, blankets) can harbor MRSA longer than non-porous surfaces. The presence of organic matter, such as dirt, dust, or bodily fluids, can further protect the bacteria by providing nutrients and a protective barrier.
Reducing MRSA Spread from Surfaces
Preventing the spread of MRSA from contaminated surfaces involves consistent hygiene and cleaning practices. Frequent and thorough hand hygiene is a primary defense; washing hands with soap and water for at least 20 seconds, especially after touching wounds or shared items, or using an alcohol-based hand sanitizer when soap and water are unavailable, helps remove bacteria.
Routine cleaning and disinfection of frequently touched surfaces are also important for reducing MRSA transmission. This includes items like doorknobs, light switches, computer keyboards, shared sports equipment, and bathroom fixtures. In homes, schools, and gyms, surfaces that come into contact with bare skin or open wounds should receive particular attention. Cleaning removes dirt and organic matter, allowing disinfectants to work more effectively.
When disinfecting, use products registered by the Environmental Protection Agency (EPA) that are effective against MRSA. These products will have specific instructions on their labels, including precautions, application methods, and the required contact time. A simple bleach solution, made fresh daily by mixing one tablespoon of bleach with one quart of water, can also be an effective disinfectant for many surfaces. Avoid mixing bleach with other cleaners, especially ammonia.