Hand hygiene is being promoted, but it is a challenge. My friend Basil, for example, was washing his hands in the bathroom of a popular hamburger franchise in England and saw a uniformed worker leave the lavatory and walk straight to the door without washing his hands...

He reported this to the manager who said that the worker claimed that although he didn't wash his hands in the bathroom, he had used the hand sanitiser in the kitchen area.

Here's another example. In the pharmacy, my co-worker received a prescription for antibiotics. The prescription was soiled and felt damp. When she enquired about the state of the prescription, the client explained that her infected ears had been running on the prescription.

Tomorrow, we celebrate World Water Day, and the theme surrounds the issue of sanitation. Hygiene will be highlighted and we will be encouraged to look at the world's sanitation challenge. In fact, 2008 has been declared by the United Nations as the International Year of Sanitation, focusing on safe collection, storage, treatment and disposal of human faeces and urine.

The scarcity of water in numerous settings worldwide creates a difficulty when it comes to sanitation and hygiene. In such settings access to toilets, coupled with improved hygiene behaviours such as hand washing with soap and water, become critically important in reducing the spread of infections. Our hands spread about 80 per cent of common infectious diseases like the common cold and flu. Some germs can live for up to two hours on surfaces like telephones, doorknobs, pens and bus rails, and most people get sick when they touch a contaminated item, then touch their eyes, nose or mouth. After toilet use, handshaking, coughing and sneezing in the hands, blowing the nose or changing diapers, it is important to clean the hands.

Alcohol-based hand sanitisers

Alcohol-based hand sanitisers (ABHSs) which do not require water, are an excellent alternative to hand washing, particularly when soap and water are not available. Hand sanitisers are expected to supplement regular, good old-fashioned soap and water, but not to replace hand washing. The active ingredient in ABHSs is alcohol, in the form of ethanol (ethyl-alcohol), iso-propanol, isopropyl-alcohol or another variation. It is an antiseptic which disinfects the skin.

Glycerine is another ingredient, which is used to moisturise the skin and prevent the alcohol from drying it. ABHSs are more effective than soap and water in killing multiple disease agents, bacteria, viruses and fungi. However, when hands are visibly soiled, soap and water are much more effective than ABHSs, at removing 'organic' material and germs. ABHSs are safe for use in children, as long as we ensure that they rub their hands until they are dry, at which point the alcohol content won't be flammable. Additionally, if the sanitised hands come in contact with the eyes, there won't be any burning, since the product would have evaporated.

Shopping for hand sanitisers

ABHSs are available in pharmacies and supermarkets in the form of a liquid, gel or foam. They are only effective in killing germs when the alcohol content is 60 per cent or higher. When shopping for hand sanitisers, look at the active ingredients to ensure that the product has 60 to 95 per cent of alcohol, ethanol, ethyl-alcohol, isopropanol or iso-propyl alcohol.

If it does not state the alcohol percentage, we may assume that it does not meet the 60 per cent standard needed to kill germs effectively. ABHSs which contain benzalkonium chloride (another germ killer) with the alcohol, are much more effective than those which contain alcohol alone.