Under the leadership of Kos Fourkiotis, innovation manager at CSU, four experts talked to each other. About bacteria, fungi, viruses and pathogens. Rob Boers, Quality, Occupational Health and Environment manager, said that CSU went looking for evidence. “Do we make healthy by cleaning? Is there a clear link? Cleaning at offices and schools is often aimed at a visual measurement and visual result. The relationship with health and well-being is actually not much of an interest to us. Technical measurements are more important in the food industry and health care. There is a zero tolerance policy with regard to micro-organisms, given their importance for health. You also have quality marks for healthy buildings, but they are based on a few studies. We therefore wanted to find out what has been researched in the world and translate that into cleaning.” That turned out to be not so easy…
The world of bacteria, fungi and viruses
Marije Willemsen, Tender Strategist at CSU, but also a microbiologist, explains the world of bacteria, fungi and viruses. “We have more bacteria in our bodies than there are people in the world. As many as 50 bacteria fit in the diameter of a hair if you could put them side by side. They are on all surfaces, but also in everything around us.” A bacterium is a very small single-celled living microorganism that multiplies by cell division. A bacterium can reproduce itself in all kinds of culture media, even in a dead organism. A fungus, also called a fungus, is an organism that lives on organic substances. “We know this from, for example, the situation in which there is poor ventilation or moisture problems. They are very intelligent networks that feed on substance and reproduce via spores/seeds in the air.” Third, she names viruses. “Those are not living beings according to our human definition. A virus is a protein with genetic material that can enter a cell and take advantage of a host to survive. That host can be a human, animal, plant or bacteria.”
Pathogens or pathogens
Bas Lemmens, Project Manager at Maastricht University added the explanation of pathogens. “In other words, spreaders.” Pathogens are microorganisms such as bacteria, fungi or viruses that can cause an infectious disease. They spread in different ways. For example through the air when coughing or sneezing, physical contact, an infected surface or through food. Lemmens: “Bacteria have an important function in our body. We carry a lot of them with us, especially in the gastrointestinal tract. They have an important function in the digestive system there.” The E. coli is a bacteria that occurs naturally in the intestines of animals and humans. Lemmens: “It helps to digest food, but can be sickening in the wrong place. If a child is born in a natural way, it gets some faeces from the mother to build up an immune system.”
Cleaning actually cuts through bacteria, fungi, viruses and pathogens, said spokesman Fourkiotis. “You actually move the micro-organisms from one place to another. You actually want to know if you carefully remove these microorganisms whether it contributes to achieving the goal. Then it helps if we understand what is happening in that world at that level.”
Touch often
Fourkiotis wanted to know from Guy Plasqui how a cleaning company can know whether a surface is contaminated or not. Plasqui is an associate professor of nutrition and exercise sciences at the University of Maastricht. “Infected immediately sounds dangerous, but it doesn’t have to be. We have micro-organisms around us all the time and for the majority of the time there is little to worry about. In places such as a door handle, a shared mouse and keyboard, the button of the coffee machine, many microorganisms, bad and not bad, come together. Microorganisms collect there because we often touch these places. If you touch such a place, you are more likely to take over one microorganism from another. These are not all dangerous, but there may be pathogens among them.”
Unable to differentiate
Fourkiotis: “So the problem for cleaning is that we can clean and break the chain there, but we cannot distinguish between harmful and non-harmful micro-organisms.” Plasqui: “You can, however, clean a frequently used source such as the toilet more frequently. Or wash your hands well. Then you prevent the micro-organisms from being transported from one place to another. That toilet is then more important than a window sill that collects dust, but where no one picks up that dust with their fingers and puts it in their mouth.”
Collect data objectively
How could you adapt your cleaning regime to this knowledge, Fourkiotis wanted to know. Lemmens: “As a university, we are in contact with CSU to see if we could objectively collect data so that, as a cleaning service, you know more specifically what you should and should not do.” A PhD researcher from the University of Maastricht then looked at 172 scientific studies in this field in order to learn from them. The problem in a nutshell? Research often involves controlled environments, for example in a laboratory. Plasqui: “You clean with a product and check before and after how many pathogens and bacteria have been removed. That in a controlled environment. Or they were studies that looked at whether micro-organisms now survive longer on wood or metal. But what does that say about an entire building where building users swarm together, different materials are used and there are different visit frequencies. In short, the studies to date are always small islands. The bigger picture we don’t have yet. It is not yet possible to draw a conclusion about the influence of cleaning on health. We do assume that we can counteract the risk of illness with cleaning. That is logical reasoning. But whether that means cleaning once or three times? Then we can’t make it hard.”
There is a conviction
Nevertheless, according to Fourkiotis, there is a belief that cleaning helps to prevent illness. Plasqui: “I think so too. You can see that it helped during the pandemic that many companies made adjustments. Think of mandatory hand washing, ventilation and more frequent cleaning. That contributes to a healthier indoor environment.” But it’s not hard to make. And as a cleaning company you don’t want to disinfect an office from head to toe, Boers notes. “It’s not a zero-tolerance environment like the food industry or the hospital. It is also not desirable to kill all micro-organisms in an office, you need some. In addition, disinfection promotes antibiotic resistance.” Willemsen: “We cannot draw the conclusion that the cleaner the better. There is a tension between preventing contamination and allowing beneficial micro-organisms to exist. For example, bacteria that help to maintain our immunity to diseases or bacteria that contribute to the digestion of food. A sterile environment is therefore undesirable.”
Smart sensors
Lemmens notes that it is impossible to continuously measure the presence of micro-organisms. “But it is possible to use smart sensors to determine how often people go to the toilet. If you collect data on this and the frequency of cleaning over a longer period of time and compare this with absenteeism, you could provide insight into the long-term effect.” You can measure with an ATP meter. This measures the amount of ATP (a substance present in all living cells) that is present on a surface. Willemsen: “All living organisms have ATP, but organic material does not measure it. In addition, this method is very local, in one place. Other measurement methods are quite cumbersome.”
Advice to stay indoors
During corona, the population was advised to stay indoors. Plasqui: “Logically, they mainly wanted to reduce contact between people. But it doesn’t make sense when you look at where viruses gather and there are several people in a room. Outside, a virus is deactivated by the UV of sunlight and you have much more ventilation. Outside is therefore always the safest place, unless you are crammed together at a festival.” UV light is used in hospitals for disinfection. Boers: “It is a good method in an enclosed space. But you don’t want people exposed to UV light. In addition: without an air stream that you let pass the UV lamp, it has little effect. All in all, therefore, the application in the food industry and healthcare is fine, but the application in a regular environment such as an office or school is limited.”