The invisible guests we carry: When clean hands aren’t enough

We often believe that washing our hands through the familiar six or seven steps we see on posters in schools and hospitals is enough. Some even sing Happy Birthday twice to make sure the wash lasts long enough. In December, when homes are fuller and routines loosen, this ritual feels especially reassuring. Yet beyond that sink there are invisible guests that survive the ritual. Germs no longer stay on our hands. They cling to the things we touch next.

I often remind my students of this when I teach Epidemiology. One of the earliest topics we discuss is the Epidemiology Triad. It explains that disease occurs when three elements interact, which are the agent, the environment and the host. If we manage the environment wisely, the agents have nowhere to move, and we as hosts remain protected. When we ignore that balance, we invite trouble.

Think about your phone. It is the first thing most people reach for when they wake up and the last before they sleep. During festive weeks, it travels even more, from long drives home to shared tables and crowded gatherings. It moves from classrooms to toilets, from the car to the kitchen, from meetings to the pillow. A study at Universiti Teknologi MARA in Puncak Alam examined 163 mobile phones used by health science students and lecturers. Every single one was contaminated. One in five carried Staphylococcus aureus, a bacterium known to cause skin infections and food poisoning. Some also had bacteria linked to fecal matter. We wash our hands carefully, then pick up the same phone that went into the toilet hours earlier.

We rarely think of cleaning our phones. A survey among medical students in Kuala Lumpur found that most of them seldom disinfected their devices or washed their hands after using them. The phone feels like part of us, yet it never gets a wash. The same quiet danger hides in the bottles and containers we carry every day. We take them to work, to lectures, to the gym, hiking outdoors, even to bed. During year-end travel, they sit in cars, backpacks, and hotel rooms. They have become symbols of health and sustainability, reminders to drink more water and use less plastic. Yet what hides inside them is not always as pure as we imagine.

A 2025 study at Universiti Tunku Abdul Rahman in Sungai Long tested bottles used by medical students and found that almost half contained coliform bacteria. More than three quarters had bacterial levels above what is considered safe. Many students said they only rinsed their bottles instead of washing them properly with soap and water. Some never cleaned the caps or straws.

I was reminded of this recently in a conversation with Mar De Guzman, an Infection Control Expert and Medical Practice Enforcement Officer at CKAPS, JKN Sabah, who noted, “We know handwashing matters and that phones and bottles should be cleaned, yet many of us simply do not make it a habit.”

Inside those familiar containers, the ones that proudly sit on our desks and car seats, bacteria quietly grow. The warmth, the moisture, and the lack of proper drying give them the perfect place to thrive. It does not matter if it is a sleek Hydro Flask, a colourful Tupperware, a practical Montigo, a polished Zus tumbler or even the famous Tyeso everyone carries now. What matters is how we clean them. Each sip from a poorly washed bottle may not cause harm right away.

Our kitchens tell a similar story. Festive cooking often stretches for hours, with many hands moving in and out of the same space. We take pride in home cooking and trust that food made with love must be safe. Yet a 2025 review by Universiti Putra Malaysia found that many cases of food poisoning begin at home. The researchers reported that unsafe storage, cross-contamination and poor cleaning habits were common causes. The same cutting board used for raw chicken often meets vegetables next. Leftovers stay on the table too long before refrigeration. Sponges remain damp for weeks. These are not acts of neglect, just habits that go unexamined. The Food Act 1983 (Amendment 2024) and Food Hygiene Regulations 2009 give clear rules to restaurants and caterers, but their spirit belongs in every home kitchen.

Recent incidents prove that hygiene remains fragile. In May this year, 43 students in a Perak school fell ill after eating Tom Yam fried rice. In July, more than 400 students in Kelantan were hospitalized after meals from an unregistered caterer. The Ministry of Health recorded over 12,000 food poisoning cases nationwide up to September 2025. Even as the year winds down, these numbers remind us how easily routine lapses turn into outbreaks.

If we look closely, we see that germs do not wait for public spaces to strike. They live in the rhythm of our days. We scroll through our phones while eating. We refill bottles without washing them. We set devices beside chopping boards. We reheat food that has sat uncovered. Germs move quietly from surface to surface. The invisible guests move wherever we move, carried by our own habits.

The solution does not need fear or perfection, only awareness. Treat your phone as part of hygiene. Wipe it each day with a clean cloth or alcohol-based solution. Keep it away from bathrooms and food preparation areas. Wash bottles properly with warm soapy water, scrub the lids and straws, and let them dry completely before use. In the kitchen, keep separate boards for raw and cooked food, refrigerate leftovers early, and change sponges regularly. These small acts are what keep the balance between the host, the agent and the environment, the same triad that guides Epidemiology. When one part is controlled, the chain of infection breaks.

As a lecturer, I always remind my students that the essence of public health is not in complicated theories or technology. It begins with awareness. Prevention is not a campaign but daily practice. It happens quietly, in homes, classrooms and canteens, wherever people choose to be careful. A clean counter, a washed bottle, a wiped phone, these are the real expressions of public health.

During the Covid-19 pandemic, we became almost obsessive about cleanliness. We sprayed every parcel, sanitized groceries and wiped car keys until they shone. It showed that hygiene is not just an individual act but a collective effort. That shared vigilance has faded, but its lesson remains. We may not need that level of intensity today, but mindfulness should remain.

Cleanliness is not about fear. It is about respect for ourselves and for others who share our space. The Epidemiology Triad reminds us that when we manage our environment, the agent cannot reach the host. When we ignore it, illness fills the gap. The same principle applies outside the classroom and inside every home.

Look around you now. As the year closes, every object you touch has a story. Your ring, your earrings, your watch, your car keys, your AirPods, tablet computer, the pen you chew while thinking, the wallet that sits on every counter. Each collects traces of where you have been. Clean them once in a while. It takes only a few minutes, a bit of soap or sanitizer. During the pandemic we went overboard, cleaning even the fruit, but perhaps that memory still holds a lesson. Hygiene is not obsession. It is awareness.

True health does not begin in hospitals. It begins in habits. The six steps of handwashing taught us how to clean what we see. The next step is to care for what we cannot. Germs will always exist, yet they lose their strength when we stop being careless hosts. The cleanest hands can still spread disease if the things around them are ignored. As we move from Christmas into a new year, clean your phone, wash your bottle, keep your kitchen honest, and remember that the invisible guests are not dangerous because they exist, but because we forget that they do.

Footnote :
Melvin Ebin Bondi is a PhD candidate in Public Health at Universiti Malaysia Sabah. He writes a weekly public health column for the Borneo Post.