Cytomegalovirus (CMV) is a common virus from the herpesvirus family. For most healthy children and adults, a CMV infection causes mild or no symptoms. However, the virus can pose a concern for individuals with compromised immune systems and for unborn babies if the mother contracts it during pregnancy. Understanding how this virus persists in the environment is a practical step for those who care for these groups.
CMV Survival on Inanimate Objects
The length of time Cytomegalovirus can remain infectious on surfaces is highly variable, ranging from a few hours to several days. This viability is influenced by the type of material the virus lands on. On non-porous (hard) surfaces like plastic, glass, and metal, CMV can survive for several hours. Studies have shown it can persist for up to three hours on glass and plastic, and two hours on metal.
The virus’s survival time often extends on porous (absorbent) materials. Materials like cloth can harbor viable CMV for at least six hours. The presence of bodily fluids, such as saliva or urine, plays a large role in its persistence. As long as a surface remains moist, the virus is more likely to stay infectious.
The amount of infectious virus particles decreases over time after being deposited on a surface. While CMV DNA can be detected for many hours, the virus may no longer be viable or capable of causing an infection. The key factor is whether the virus remains in a moist environment, which allows it to maintain its infectious structure. This is why a damp cloth or a toy still wet with saliva might pose a greater risk than a dry surface.
Effective Disinfection Methods
Eliminating CMV from household surfaces can be accomplished with common cleaning agents. Simple soap and water are effective for cleaning hands and surfaces by physically removing the virus. For disinfection, alcohol-based solutions, including 30% ethanol or isopropanol, are effective against herpesviruses like CMV.
Commercially available disinfecting wipes and sprays registered with environmental protection agencies are also reliable. When using these products, it is important to follow the manufacturer’s instructions for contact time—the duration the surface must remain visibly wet. Other effective chemical disinfectants include 1% sodium hypochlorite, the active ingredient in bleach.
Pay special attention to high-touch surfaces, particularly in settings with young children, such as daycare centers or homes with toddlers. Items like changing tables, doorknobs, countertops, and toys are frequent points of contact. Regularly cleaning these areas can help reduce potential virus transmission from surfaces.
Primary CMV Transmission Routes
While it is possible for CMV to be acquired from a contaminated surface, the virus is most commonly spread through direct and prolonged contact with infected bodily fluids. The virus can be present in saliva, urine, tears, blood, and breast milk. Activities like sharing food or utensils, kissing a child on the lips, or handling diapers can transfer the virus.
This is a primary reason why CMV is so prevalent among young children, especially in group settings like daycare facilities. Toddlers often share toys that have been in their mouths, have close physical contact, and are not always proficient with hand hygiene. This environment facilitates the easy exchange of bodily fluids, making it a common setting for CMV to spread among children.
While disinfecting surfaces is a useful practice, preventing direct contact with infected fluids is a more targeted approach to prevention. Frequent and thorough handwashing with soap and water is one of the most effective strategies to prevent the spread of CMV. This is particularly important after changing diapers, wiping a child’s nose or drool, or before preparing and eating food.