fomites

Fomites are inanimate objects or materials that can carry infectious agents and facilitate indirect transmission of disease. When a person touches a contaminated surface and then touches their mouth, nose, or eyes, the pathogen may enter the body. Fomite-mediated transmission is one route of infection alongside direct contact, droplets, and airborne spread. The risk depends on pathogen viability on the surface, the amount of contamination, the frequency of contact, and host susceptibility, as well as cleaning practices.

Common fomites include door handles, light switches, doorknobs, mobile devices, countertops, keyboards, towels, medical equipment like stethoscopes, and shared utensils. Nonporous surfaces tend to retain infectious agents longer than porous materials, though some organisms can persist on fabrics and textiles.

Pathogens that can be transmitted via fomites include viruses (for example norovirus, influenza, coronaviruses), bacteria such as Staphylococcus aureus and MRSA, and spore-forming organisms like Clostridioides difficile. Survival times vary from hours to days or longer, influenced by environmental conditions such as temperature and humidity.

Control measures emphasize regular cleaning and disinfection of frequently touched surfaces with approved agents, along with hand hygiene, proper laundering of textiles, and avoidance of touching the face. In healthcare and food-service settings, protocols include routine environmental cleaning schedules and, when appropriate, isolation or contact precautions.

Judgment about the role of fomites in outbreaks should be based on epidemiological evidence, as transmission is often multifactorial. Fomites are a recognized, but not universal, pathway for infectious disease spread.