Every day we come into contact with things that we don’t realise are coated in germs: banisters, car doors, even newspapers. Every time you touch something that’s been touched by someone else, you’re exposing yourself to the microbial melange on that stranger’s hands.

Now here’s where it gets even scarier: Dr. Myriam Sidibe, a renowned global expert in public health, told a 2014 TED Talk audience that an estimated 80 percent of people don’t wash their hands after using the toilet.

The solution is so simple for those of us with access: just wash your hands with soap and water, often.

Why should you wash your hands?

Poor hand hygiene has serious consequences: People don’t realise how often they touch their face, eyes, or lips, spreading bacteria, viruses and general microscopic grime with each touch. These germs can cause a host of respiratory and digestive illnesses, some trivial, some serious. The U.S. Center for Disease Control and Prevention estimates that, worldwide, 2.2 million children under the age of 5 die every year from diarrhoea and pneumonia—two diseases commonly spread by this kind of casual contact and highly preventable by washing hands.

When should you wash your hands?

You should wash your hands:

• before and after preparing food
• after handling raw meat, poultry, or fish
• before and after eating any food
• before and after attending to someone with an illness or injury
• after using the toilet
• before and after changing a diaper
• before wearing or removing contact lenses
• after handling garbage
• after coughing, sneezing or blowing your nose
• before and after applying medication, such as eye drops or pain relieving gels

Washing your hands several times a day keeps them free of germs and reduces the risk of catching or spreading infections. You – and your family – will be healthier for it. For this reason, it’s best to instil the habit early in kids’ lives.

Can you use hand sanitizer instead?

You can use hand sanitizer – but only when you don’t have access to soap and water. Sanitizer marketing makes it seems as if the gel is a substitute for soap.  It’s not.  In a Soap vs Sanitizer battle, soap wins, hands-down.

The combination of running water, soap and scrubbing physically removes germs from your skin. Hand sanitizer only kills some germs and, according to studies, is ineffective against norovirus, which causes gastro-intestinal distress, and clostridium difficile, which causes intestinal diseases and can be fatal.

If soap and water just isn’t available, hand sanitizer is better than nothing—but only if it contains at least 60 percent alcohol. So keep a hand sanitizer handy for emergencies, but don’t rely on it.

How should you wash your hands?

To get the most out of soap and water, wet your hands with clean running water, take a little soap, and lather. Scrub your entire hand, front and back, for at least 15  seconds. Be sure to dry your hands using a clean towel or a fresh paper napkin. Repeat as needed.