The 'hows' and 'whys' of hand sanitisation

Monday, 16 March 2020

Hand hygiene and sanitisation came to the forefront of disease control in the late 19th century when, in 1847, a Hungarian physician called Ignaz Semmelweist, observed a higher mortality rate amongst women who had been assisted in childbirth by doctors as opposed to midwives. Semmelweist noted that these doctors often came from performing autopsies on patients who had died from infectious disease. He enforced a strict policy of hand washing in between seeing different patients and mortality rates dropped from 18% to 2%. This clearly demonstrated that the simple act of hand washing could significantly reduce the transfer of disease.

Hand hygiene is now a recognised practise for disease control but what is the most effective way of killing the germs, in particular the Coronavirus?

Coronavirus is an envelope virus, this means it’s inner genetic core is protected by an outer layer of fat. On this outer layer there are little spikes, which upon entering the human body allow the virus to attach to the host (us) and start an infection. Soap and alcohol both work by breaking down this outer layer of fat and destroying the spikes. This renders the virus unable to attach itself and therefore useless. Washing with water alone has no direct effect on the virus.

The advice from the World Health Organisation (WHO) and the NHS is to wash your hands frequently with soap and water and if soap isn’t available to you, for example if you are travelling, then use an alcohol-based sanitiser. Hand sanitisation should be done every time you reach your 'safe place', which could mean your home, your desk, or seat on public transport. Be mindful of what you touch and don’t touch anything unnecessarily. Avoid touching your face.

Hand washing is considered better than using hand sanitisers but it has to be done correctly if it is to be effective. The NHS show in their video that the hands should be lathered up on both sides, between the fingers and under the nails and rinsed under running water for at least 20 seconds to wash the virus away. If possible, a disposable towel should be used to dry hands, which can then be used to turn off the tap before throwing it away. For hand sanitisation through alcohol based gels, there needs to be at least a 60% alcohol content to be effective. Most sanitisers contain 60-95% alcohol; however some brands designed for sensitive skin contain no alcohol at all.

On a final note, with all the hand washing the skin is likely to become dry and cracked. In addition to being sore, this can further increase the chances of infection, so it is important to keep the hands well moisturised.