Of all the measures needed to maintain good health, something simple like a good hand washing is arguably the most useful.The World Health Organisation says the number of healthcare associated infections at any given time is 15.5/100 new patients and even  up to 31 in surgical setting. Same applies to  individuals anywhere. Dirty hands become a source of transmitting infections between individuals. Hand washing can prevent transmission of many infections such as cold, cough, diarrheal diseases, typhoid, etc.One should always wash hands after going to the toilet. While preparing, serving or eating food, hands should always be washed.  Wash hands after handling raw food material, particularly meat. After coughing or sneezing, it is advisable to wash hands to remove contamination of germs. Similarly, hand washing is also advisable after touching animals. One may keep cats or dogs as pets and fondle them affectionately. But animals harbour germs on their body, tongue and paws, which can cause infection to humans. It is said that one needs to wash hands after contact with body parts of other persons except clean hands. But here is the million dollar question: Hand touching by means of hand shake is the most common physical contact with another human being, how can one be sure whether the hands of the other person are clean or not? Whether to wash hands after hand shake is debatable. Maybe with this risk in mind, the traditional form of greeting in most Asian societies was to bow or greet with folded hands, not a "hand shake”. However, simple as it might sound, one should know the correct technique of hand washing. A good hand washing involves use of soap and adequate amount of  water. Ideally, warm water should be used because that serves as antiseptic, but considering the high price of fuel, that can be skipped.  Rub hands thoroughly with soap till the count of 10 to 20. Soap should be scrubbed well over tips of fingers and in between fingers, under nails and back of hands, to remove all possible contamination. The scrubbing movement should begin from center of the hand to the peripheral edge. This prevents any potential movement of grime or germs from periphery to center. After scrubbing with soap, rinse the hands adequately with water to remove any traces of soap.Washing hands is not only good to prevent diseases but also has an aesthetic value. Clean, scrubbed hands look more pretty than hands with grime or oil, however well-manicured they may be. Smelly hands do not appeal to anyone.Handkerchiefs and disposable tissues though used much are no substitutes for a hand wash regarding cleanliness and hygiene. However busy you might be, one needs to remember the simplest means to remain healthy is to wash hands regularly.Dr Rachna Pande is a specialist in internal medicine at Ruhengeri Hospital