Woman washing her hands at the sink.

Since the coronavirus surfaced in early January, governments around the world have been in a battle of preparedness. The number of infections is also increased in our regions. However, scientifically based directions to this are often overshadowed by disinformation. What information is correct and above all: what can we do ourselves? The simplest advice turns out best: wash your hands more often and in a correct way. The effective drying of the hands, with a paper towel or a qualitative hand dryer, is an often forgotten but not to be underestimated step.

How is the coronavirus spread?

Research by the Chinese Center for Disease Control and Prevention (CCDC) shows that the coronavirus (covid-19) spreads through ‘drip dispersal’ – in other words, the virus only passes from human to human through the tiny droplets released during coughing and sneezing. According to recent studies, it travels on coughed-up droplets larger than 5 to 10 microns (one thousandth of a millimeter), which quickly fall down again, and thus end up on the surfaces that surround us.

The Dutch National Institute for Public Health and the Environment (RIVM) states that one assumes a distance of up to two meters: the virus does not ‘fly’ any further than that. Moreover, there is no clear evidence that the virus can stay in the air for a longer period of time and spread in this way. This means that the coronavirus is not proven to spread through air, air blowers or air conditioning systems. The World Health Organization (WHO) also confirms that only those who inhale droplets or enter through the hands in the mouth can become infected.

How can we prevent the spread of the coronavirus?

At this time, there is no vaccine for the coronavirus available. Prevention in this is better than cure. Medical professionals and governments rightly stress that hygiene is the key word in the fight against covid-19, and one refers specifically to the importance of good hand hygiene. Washing hands regularly and thoroughly with soap and water is proving to be one of the most efficient ways to protect yourself and others. If this is not done in the correct way, then this action misses its effect. Even the efficacy of disinfectant hand gel decreases if you do not wash your hands properly first, says Professor Marcel Zwietering (Professor of Food Microbiology at Wageningen University & Research).

However, what is not sufficiently mentioned in the news coverage is that drying your hands properly is at least as important. However, drying the hands is accompanied by a lot of risks of re-contamination. Wet or moist hands are breeding grounds for bacteria and spread up to a thousand times more bacteria on the surfaces they touch. The two leading international health organizations, the World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC), therefore prescribe to dry hands with a paper towel or an air hand dryer.

Are electric jet dryers safe with regards to coronavirus?

During a toilet visit, several contaminated surfaces are often touched, both before and after hand washing: opening the toilet door, opening and closing the tap and touching the towel roll, paper towels or button of a hand dryer. All these surfaces can be contaminated with bacteria by contact.

Since the coronavirus in particular is spread by touch and most jet hand dryers are operated completely hands-free, you avoid unnecessary – and therefore risky – touches. When using paper towels, you are more likely to pass on the coronavirus through touch. Also a regular towel or a cotton-roll system are not good alternatives, since that way you can also get bacteria or viruses from other users.

Some jet hand dryers are equipped with a HEPA filter and ensure that almost all bacteria are filtered out of the air before they blow your hands dry. Up to 99.95% of the particles are removed from the air before it lands on your hands. Partly for this reason, such jet hand dryers are used in modern hospitals. Similarly, in the disinfection areas of the special hospitals built in China to treat coronary patients hand dryers with HEPA filter have been installed, such as in the Shenyang Infectious Disease Hospital.

HACCP International, a leading food technology organisation, has certified a number of electric hand dryers as hygienic. The HACCP certificate guarantees that the appliance meets the highest requirements regarding the process of hand hygiene. Because, among other things, contamination is a constant threat in areas where food is produced, such hand dryers are ideally suited for this.

However, there are reports that hand dryers are blowing around bacteria and viruses, but these are unfounded. The researchers behind these studies – which were funded by the paper industry – did not use a methodology that reliably simulates its use in a realistic setting. There is therefore no scientific basis to support the claim that jet hand dryers with HEPA filter are unhygienic or spread bacteria and viruses.

There is no doubt that hygiene is number one in the fight against coronavirus. Washing hands and – remember – drying them thoroughly afterwards, with a paper towel or a good hand dryer, is the recommendation when it comes to preventing further contamination.