The World Health Organisation's (WHO) World Hand Hygiene Day takes place this Saturday. It's a timely reminder of the role of careful hand-washing in reducing illness and helping the fight against antibiotic resistance, explains Julia Moloney.
1. You're probably washing your hands all wrong.
"Most people, when they wash their hands, they sort of give them a quick run under a tap, with no particular method," says Martin Cormican, Professor of Bacteriology and consultant microbiologist. "People commonly miss the fingertips, the spaces between their fingers and the thumb."
Proper technique has a dramatic impact on the effectiveness of hand-washing in removing germs. "And," says Prof Cormican, "the fingertips are particularly important because that's what you touch things with. If you're eating finger food, you use your fingertips. If you want to take something out of your eye, you use your fingertip. They are what we use, mostly."
2. A proper wash of the hands takes 40-60 seconds
Which, as a guide, is about the time it takes you to sing Happy Birthday twice. According to the 'How to Handwash' guide from the WHO, you should get a good lather going, and then spend a few seconds on each of the following: rubbing hands palm to palm, rubbing the backs of the hands with interlaced fingers, rubbing palm to palm with fingers interlaced, rubbing the backs of the fingers to the opposing palms with fingers interlocked, rubbing your fingertips against the opposite palm, working around the fingernails, grasping each thumb in the opposite palm and rubbing. Don't forget to lather the wrists.
If possible, it's best to turn off the tap with your elbow or a clean towel when you're finished. If you use your now-clean hand, you're going to be retrieving some of the germs that you dropped off there at the start of the process.
3. Cough into your elbow, not your hand
When no tissue is available, people regularly cover their mouth with their hand when they sneeze or cough, as a polite bid to limit the spread of germs. But a more effective technique is to use the crook of your arm instead. That way, if you touch a handrail, doorknob or lift button a few moments later, you're less likely to leave a trail of pathogens behind you.
4. You don't need fancy soaps
Prof Cormican is dead set against the army of antibacterial household products that have sprung up in recent years. "I don't recommend them at all," he says. "There's very extensive and very aggressive marketing of antibacterial things in everything, and part of that, I think, comes from the mistaken idea that most bacteria are dangerous. They're not. Most bacteria are good. The world wouldn't work without bacteria. There's a small number of bacteria that from time to time cause trouble, and we have to manage those."
Using household disinfectants can help create superbugs. "If you use anything that kills bugs, what you do is you give an advantage to the bug that is resistant," he says. For hand-washing, you need nothing more elaborate than plain old soap and water. "In an ordinary domestic setting, bar soap is fine and the most environmentally-friendly option," he adds.
5. You're more likely to get sick from germs you touch than germs you breathe
"We think of colds as being spread in the air. There is an element of truth in that, but a lot of the spread is from droplets on surfaces," explains Prof Cormican.
Some of the common infections transmitted by hand contact include "respiratory tract infections, colds, mainly caused by viruses", he explains. "Those viruses are shed in respiratory secretions; spit, droplets that come of out of the mouth. Very often those droplets land on the desk or they land on the computer keyboard, so when somebody puts their hand down on the surface where the virus is, they get the virus on to their hands from where they can transmit it into their mouth or their eye or nose."
Stomach bugs such as norovirus are also easily spread this way as well as common bacterial infections such as Staphylococcus Aureus, which causes skin infections like boils and impetigo.
6. Try to remember to wash your hands whenever you arrive home
There's no fixed number of times a day you should wash your hands. "For most people, what we're looking for is trying to find a balance between washing your hands a reasonable number of times and making sure that this doesn't interfere with you having a normal life," says Prof Cormican.
"In a family setting, it's really very difficult to avoid sharing bugs. The way most of us live in a normal home, you don't want to be washing your hands every time you have social contact with your family. But I think that what you can do is if everybody tries to remember to wash their hands when they come home, then that reduces the chances of introducing something new to the house."
As a guide, he recommends carefully washing your hands with the appropriate technique "before you prepare food, after you've been to the toilet and when you come home. Particularly if you've been in contact with a lot of people or with animals in the course of your work."
7. Take extra care with handwashing if you are pregnant, immunosuppressed, or visiting a hospital or a GP surgery
Hand hygiene becomes especially important in healthcare settings where bugs are abundant and patients are often especially vulnerable. Also "anybody who has been given a medication that they have been told might interfere with their immune system should probably be extra careful," says Prof Cormican. "And it's probably a good idea for people to be extra careful when they're pregnant, because the immune system is switched down a little bit during pregnancy. People who are frail or in ill health should also take extra care."
8. Hand hygiene plays a big role in the fight against antibiotic resistance
If we succeed in reducing the spread of infection through good hand-hygiene "we need fewer antibiotics. And the fewer antibiotics we use, the less antibiotic resistance we have", says Prof Cormican. Resistant bugs, he says: "Spread the same way that other bugs spread - mostly on contact and on hands. And if you keep things clean that stops bugs spreading, and that works just as well for antibiotic-resistant bugs as it does for other bugs."
9. If you cannot get to a sink, hand sanitiser can be a useful stopgap
If there is no soap and water close by, an alcohol-based hand sanitiser will effectively eliminate most harmful bacteria, according to official advice from the Centers for Disease Control and Prevention (CDC) in the US - though it will not be very effective if hands are visibly dirty or greasy. Choose one that contains at least 60% alcohol, and you should still wash your hands with soap and water as soon as possible.
10. Hand washing really does help people stay healthy
According to statistics from the CDC, proper education within communities about hand washing has the effect of reducing the number of people who get sick with diarrhoea by 31%, reducing diarrhoea-illness in people with weakened immune systems by 58%, and reducing respiratory illnesses, like colds, in the general population by 16-21%. "The key thing is," says Professor Cormican, "that if you wash your hands very regularly during the day using a good method that gets the bug off your hands, then that reduces the chance that you will get the bug into your mouth or into your eyes or nose where it can cause infection."