When we think of the dirtiest objects in the home or office, the toilet seat is often the first to come to mind, even if the reality is very different. Various research has discovered and confirmed that many of the things we touch every day host a much higher quantity of bacteria than the bathroom. The reason is simple: we clean the toilet regularly because we associate it with germs, while we neglect objects that we handle dozens of times a day.
The smartphone: a concentration of bacteria
The mobile phone is probably the most contaminated object we own. One study found that cell phones carry ten times more bacteria than most toilet seats. Researchers analyzed the devices of high school students and found more than 17,000 copies of bacterial genes on their phones.
Serious pathogens such as Streptococcus, MRSA and E. coli have been identified on cell phones. Charles Gerba, a professor of microbiology at the University of Arizona, explains that we carry phones everywhere, even into the bathroom. When the toilet is flushed, germs become airborne and end up on the device. Taking your cell phone into the bathroom is equivalent to not washing your hands after going out.
Human skin is naturally covered in microbes that usually don’t cause problems. It is these bacteria, together with the oils from our hands, that pass over the phone every time we check a message, since, in addition, the heat produced by the processor and the humidity create the perfect conditions for bacterial proliferation.
The computer keyboard: a paradise for germs
Research from the University of Arizona cited by CBS revealed that the average desk hosts 400 times more bacteria than the toilet seat. Keyboards shared between multiple people have particularly high concentrations of dangerous bacteria such as E. coli, Staphylococcus aureus, and streptococcus.
Some of these germs can survive for up to 24 hours on surfaces, and the viruses that cause respiratory infections can persist on keyboards and other surfaces shared by multiple people. Fingers and hands become contaminated with all types of germs throughout the day, and the keyboard becomes a deposit of this bacterial load.
One study examined keyboards used in hospitals and found that they were colonized by bacteria in 98.5% of cases. The tiny gaps between the keys provide shelter for food particles, dust and bacteria, making cleaning particularly difficult. Additionally, many of us eat at our desks, providing additional nourishment to the microorganisms that reside there.
The computer mouse: touched but never cleaned
The mouse is another device that is rarely cleaned but that we touch constantly. Experiments have shown that mice can harbor hundreds of bacterial colonies, in some cases at double the levels of the toilet seat. The hand rests on the mouse for hours every day, continually transferring bacteria from the skin to the device.
Studies have identified the presence of Staphylococcus aureus and E. coli on computer mice. The problem is exacerbated by the fact that we often use the computer while eating, spreading food residue that encourages bacterial growth. In shared environments, such as offices or libraries, the risk of contamination increases as the device passes from hand to hand.
The remote control, the often forgotten object
Laboratory research has found that the average remote control carries very high levels of Enterobacter, a type of bacteria found in feces, 15 times higher than the toilet seat. The study also found moderate levels of yeast and mold, as well as strep.
Each person touches the remote control about 5,475 times a year on average, and a good 25% of people never clean it. Enterobacter can spread diseases and infections, including blood infections and pneumonia. We touch the remote control after using the bathroom, while eating, when we are sick, continually transferring germs to its surface.
In hotel rooms and hospitals, where remote controls are used by many different people, contamination levels can be even higher. Yet these devices are rarely sanitized between guests.
Handles and switches: high-touch surfaces
A study by UK supplier Furniture At Work revealed that door handles in offices have 30 times more bacteria than a toilet seat. The researchers used an ATP monitoring system commonly used in hospitals, measuring 648 relative light units on the handle versus just 21 on the toilet seat.
On average, the light switch hosts over 200 bacteria per square inch, an aspect that earns it decidedly high scores in the always unrewarding comparison with the toilet seat.
The reason is simple: we touch handles and switches with dirty hands before washing them. These objects are found in high-traffic environments where many people touch them daily. Coughing, unwashed hands and continuous contact promote microbial transfer.
How to protect yourself
The good news is that most bacteria on these items are not dangerous to healthy people. Only about 0.1% of the microbes we encounter daily are pathogenic, because the immune system readily eliminates most infections.
The key is regular cleaning. Smartphones should be sanitized with slightly damp microfibre cloths, avoiding excessive liquids. Keyboards and mice should be cleaned with disinfectant wipes at least once a week, remote controls should be sanitized monthly, more often if someone in the house is sick, while as for handles and switches, a daily wipe with disinfectant products will do just fine.
Above all, washing your hands remains the most effective defense. Never use your smartphone in the bathroom and avoid touching your face after handling common objects. These simple habits dramatically reduce the risk of infections, protecting your health without having to become obsessed with germs.
