There’s concern that the sudden overuse of hand sanitisers during the current pandemic in our attempt to protect ourselves from COVID-19 may be creating an environment where antimicrobial-resistant microorganisms can emerge.
Over the past few weeks we’ve received a couple of queries from readers about the use of hand sanitisers, including does using sanitisers at the current level of usage impact on antimicrobial resistance, and what can someone do if they can’t or prefer not to use a sanitiser or wish to avoid using alcohol-based sanitisers. These are all good questions so we did some research and here’s what we found.
How Sanitisers work
Firstly though, how do sanitisers work? The alcohol contained in hand sanitisers breaks down the fatty layer that holds a virus, like the SARS-CoV-2 virus that causes COVID-19, together. Once this layer is destroyed, the virus basically falls apart and is no longer viable. Great, we’ve killed the virus and it can no longer replicate or do harm. But do hand sanitisers contribute to antimicrobial resistance?
Sanitisers are intended to be used at times when it is difficult to wash hands properly with soap and water, such as when a person is out shopping or stopping for a coffee or bite to eat while away from home. They are also used in aged care facilities and services, often as a precautionary measure before providing assistance to a resident or client.
The World Health Organisation describes antimicrobial resistance as the changes or mutations that happen to microorganisms (such as bacteria, fungi, viruses, and parasites) when they are exposed to antimicrobial drugs (such as antibiotics, antifungals, antivirals, antimalarials, and anthelmintics) which then lead to the medications being ineffective in controlling or destroying the microorganism.
Microorganisms that go on to develop antimicrobial resistance are sometimes referred to as “superbugs”.
While antimicrobial resistance occurs naturally over time, our overuse or misuse of medications speeds up this process. When we fail to complete a course of antibiotics, or don’t take the prescribed dose at the correct time intervals, the chances of resistant strains of bacteria surviving and multiplying increases.
This pathway to antimicrobial resistance is relatively well-known, so much so that managing infections and taking action to minimise the development and spread of antimicrobial resistance has been embedded into the latest Aged Care Standards (Standard 3gii). But we’re learning that some bacteria are becoming more tolerant of antibacterial sanitisers. In fact, researchers discovered that bacteria samples collected after 2010 were up to 10 times more tolerant to a disinfecting alcohol solution to samples collected in the late 1990’s. This was after hospitals in Australia began installing hand sanitiser dispensers and encouraging the use by staff and visitors in the early 2000’s.
Alcohol Based Sanitiser
However this doesn’t mean that anti-bacterial hand sanitisers don’t have a place in managing infections or controlling the spread of the coronavirus. They just need to be used with discretion and at the correct strength.
And just like antibiotics need to be taken at the correct dosage level to be effective, so too does the alcohol concentration need to be correct. The alcohol used in sanitisers is either ethanol or isopropanol and researchers have found that the concentrations with the best results against SARS-CoV-2 for ethanol is 60-70% and for isopropanol (i.e. isopropyl alcohol) around 70%. The Australian Government, Therapeutic Goods Administration recommends using a hand sanitiser that contains at least 60% alcohol to be effective against the coronavirus.
So alcohol tends to be a key ingredient due to the efficacy of being able to neutralise and/or kill bacteria and viruses, but some people are reluctant to use these sanitisers.
What’s the issue with alcohol-based hand sanitisers?
Apart from potential long-term antimicrobial resistance, concerns have been raised relating to the use of alcohol-based hand sanitisers, including religious objections, the potential for abuse, and flammability.
People have the right to choose not to use alcohol-based sanitisers due to religious beliefs, and facilities supporting people who have a history of alcohol abuse may also wish to limit contact with any product that contains alcohol, even though most hand sanitisers contain denaturants – products to deter people from unintentional ingestion by making them taste bad. But this limits the options available to people outside of soap and water when dealing with the coronavirus.
Additionally, although alcohol-based hand sanitisers can inactivate many types of microbes very effectively when used correctly, people may not use a large enough volume of the sanitisers or may wipe it off before it has dried. Like hand-washing with soap and water, people need to use a sufficient quantity of the sanitiser to allow for a full 20-30 seconds of cleaning. Most people I have seen tend to use a very small amount so that it dries off quickly and they can get on with whatever they are doing. While the World Health Organisation does not recommend a specific volume of sanitiser, they do recommend “covering all surfaces of the hand”.
And then there is the drying effect of alcohol-based sanitisers, and for some people skin irritation, although using a hand cream regularly can help to address this issue.
What are the alternatives?
Unfortunately, when it comes to the coronavirus, there is only one alternative – soap and water.
But what about Non-Alcohol Based Hand Sanitisers?
Non-alcohol based sanitisers (NABHS) are less of a problem when it comes to potential alcohol abuse or flammability and are generally acceptable to people who wish to avoid using alcohol sanitisers on religious grounds. Their primary active ingredient is usually benzalkonium chloride, which is classified as a quaternary ammonium compound (QAC). While research has shown that benzalkonium chloride can work well for bacteria and fungi, it is less effective against viruses – including the coronavirus. The Australian government does not recommend QAC-based hand sanitisers for use against COVID-19 and this is likely due to the current evidence that these compounds have insufficient efficacy against COVID-19.
What about using Metals as a disinfectant and antiviral agent?
This was an interesting idea so I did quite a bit of research on the efficacy of using metals such as silver as an antiviral. After all, you can get silver infused bandaids to assist with the healing process. Unfortunately, despite what a lot of ‘blogger’ sites touted, I could find no peer reviewed evidence that supported using silver or copper as an effective sanitiser. It’s not that metals don’t work, it’s the time that it takes for them to be effective – approximately 4 hours to inactivate a coronavirus.
So what do we do?
Well it looks like it’s back to the plain old soap and water, and I do mean plain. There is currently no evidence that antibacterial soaps are any more effective at preventing illness than washing with plain soap and water. In fact, some data suggests that using these cleaning products could increase microbe resistance.
Try this tip from Mary-Louise McLaws, a member of WHO and Professor of Epidemiology, Healthcare Infection and Infectious Diseases Control, UNSW.
“Rather than buying an ineffective alcohol-free handrub, you’re better off filling up a drink bottle with water and detergent and using it to thoroughly wash your hands when there are no bathroom facilities available.” (Just don’t confuse it with your regular drink bottle!)
And really, that should be our first choice each time. Backed up by Government and regulatory advice relating to effective Hand Hygiene which promotes proper hand-washing with soap and water as the first preference.
Soap and water are your best friends
A scientist, who succumbed to Norovirus, a very contagious virus that causes acute gastroenteritis while on a cruise ship, later studied ways to control outbreaks, as having hand sanitising stations strategically placed around the ships appeared to have minimal impact. Her research noted that hand washing was the most effective and under-rated response.
According to the WHO, people should wash hands regularly with soap and water. If you don’t have access to soap and water, sanitisers that contain alcohol are “the only known means for rapidly and effectively inactivating a wide array of potentially harmful microorganisms on hands” – including COVID-19.
So this October 15th, lets celebrate good old soap and water.
Global Handwashing Day
Getting everyone in the world to practice hand hygiene is the goal of Global Handwashing Day, an October 15th event.
If you can think of someone else who might benefit from this article, send them a link. We’d appreciate it! And if you’re looking for more helpful resources, why not check out our Resource Hub? We have culturally appropriate, tailored resources that are designed to make your job simpler and help you provide quality care to your clients. Click here to find out more.