Misleading hand gel sanitizers… waist of money?
April 10, 2010
New study reports: hand gels are misleading, only killed 60 per cent of germs at best.
• Hands on proper hand hygiene!
Last year, when swine flu hit, sales of some products rocketed by 70 per cent. Yet do hand gels really help? A study carried out in December 2009 by Ottawa University found that some brands that claimed to kill ’99 per cent’ of germs did not – at the very best they killed 60 per cent, and at worst just 46 per cent.
A dailymail report describes:
“The Medicines and Healthcare Products Regulatory Agency says it has had to investigate numerous hand-cleaning products for making claims that they can kill specific viruses such as swine flu or MRSA. They are not allowed to make these claims, because it gives the impression they have some medical effect. Gels can only really help kill everyday germs, such as those that cause the common cold. Yet few people realise that the hands have to be clean in order for many hand gels to work.
‘Like many cleaning agents, most hand gels will be less effective in the presence of protein matter, such as food, mud, faecal matter or blood,’ says Dr Ron Cutler, a microbiologist from Queen Mary, University of London. ‘You really need to wash off all visible signs of dirt before they will be totally effective.’ Many hand gels contain alcohol, which kills germs by attacking their outer membrane. For maximum benefit, a hand gel should contain at least 62 per cent alcohol – but no more than 80 per cent. This is because the gel should contain some water, as once the outer membrane of the bacteria or virus has been penetrated it is water that kills it.
But new research suggests that hands gels won’t protect against gastroenteritis or viral stomach bugs such as norovirus. Furthermore, a recent study by the Agri-Food and Biosciences Institute, Belfast, found that even Spirigel, the alcohol-based gel used in NHS hospitals, stops working within seconds of use. A non-alcohol gel offered much longer protection, killing viruses for up to 24 hours after it was applied.
Should we abandon alcohol hand gels? Non-alcohol gels work in a variety of ways. Byotrol, the gel used in this study, contains mainly water, but the gel forms an invisible layer that stays on the hands and literally pulls bacteria and viruses apart. Some others, such as No Germs, use chemical antibacterial agents or even essential oils. ‘When alcohol hand gels were first introduced years ago, it was so much better than anything else,’ says microbiologist Stephen Falder, who helped develop Byotrol. ‘But if you were going to start designing a hand gel now from scratch, you would abandon alcohol.’
He adds: ‘Alcohol stops working almost as soon as it’s dry, and does not give you residual protection.’ other experts disagree and say that while the effects of non-alcohol hand gels may last longer, alcohol is better at killing germs.
Professor John oxford, a virus expert from St Barts and Royal london Hospital, says he would always prefer an alcohol-based gel. ‘Yes, it might not work against things like norovirus, but norovirus is a very difficult bug to get rid of and nonalcohol gels won’t work against it either – little will. ‘The alcohol ones do work and certainly work against things like swine flu.’
Mr Cutler backs him up. ‘If my hands were dirty, I would wash them first with soap and water, using lots of agitation. ‘This cleans off all visible dirt. I would then apply an alcohol hand gel to get rid of any residual bacteria. ‘There are non-alcohol based products, some for example contain citrus oils, but I am not sure how strong an alternative these are. Washing your hands is the best option. ‘This should definitely be done after you go to the loo, after changing a nappy, after you sneeze, before you eat, before preparing food and after handling raw foods such as meat.’”
“‘You need to wash both the palms and the finger tips and around rings of the fingers, as bacteria can lodge there,’ says Dr Anthony Hilton, a reader in microbiology from Aston University. ‘Then you should dry with a paper towel or hand drier. However if this is not available, then alcohol-based hand gels can be a very good substitute.’”