When influenza is at epidemic levels, the focus turns to ways to lower the risk of catching this form of virus that circulates on a seasonal basis. The best way to lower the odds off getting the flu is to get a seasonal flu vaccine. However, the influenza vaccine isn’t 100% effective. Its coverage varies on a yearly basis and some years it’s mostly a miss. Vaccine developers have to take their best guess at which strains will be most prevalent when formulating the vaccine and sometimes they’re wrong. That’s why it’s important to protect yourself in other ways, even if you get the vaccine.
Certain groups of people are at especially high risk of influenza and of developing influenza complications. These include children under the age of 2 and adults over the age of 65. Women who are pregnant and individuals who have other health problems are also at higher risk. That’s why taking precautions during flu season is so important.
One form of protection you hear a lot about are hand sanitizers. You’ve probably seen them on store shelves and in offices where workers use them to sterilize their hands when they don’t have access to soap and water. If you wash your hands correctly, which many people don’t, soap and water may be almost as effective as a hand sanitizer at reducing the transmission of viruses that cause influenza and the common cold. However, hand sanitizers that contain alcohol have a slight edge over soap and water. One study found that hand sanitizers made with ethanol were MORE effective at killing cold viruses than soap and water. Plus, there’s the convenience factor and the fact that hand sanitizers keep your hands germ-free longer than soap and water. Who has time to run to the bathroom every hour for handwashing?
Another thing to keep in mind when deciding between a hand sanitizer and soap and water. Hand sanitizers kill influenza viruses, but they aren’t as effective at eradicating other pesky viruses that make their rounds in the winter, including norovirus. So, washing with soap and water could provide more broad-based protection. This assumes, of course, that you’re using correct handwashing technique and not holding your hands under running water for 5 seconds and assuming they’re clean.
All Hand Sanitizers Aren’t the Same
When choosing a hand sanitizer to use during flu season, what should you look for? The most effective hand sanitizers are high in alcohol. Studies show that the more alcohol a sanitizer contains, the more effectively it kills influenza viruses. The average hand sanitizer has around 62% ethanol or alcohol, while the Centers for Disease Control and Prevention recommends that hand sanitizers contain between 60 and 95% alcohol to ensure effectiveness. Unfortunately, some hand sanitizers available at discount stores have an alcohol content as low as 40%, which may not be effective. If you buy hand sanitizers, do your research beforehand and make sure the brand you choose has a minimum of 60% alcohol.
Some hand sanitizers contain other germ-killing ingredients, including povidone-iodine, benzalkonium chloride or triclosan but that doesn’t necessarily make them healthier for you or the environment. One, in particular, triclosan, is under scrutiny due to concerns that this chemical impacts hormone balance in the body as well as concerns about its environmental impact. In fact, the FDA has dictated that this chemical, as well as a few others, be phased out of anti-bacterial products.
Another concern is that anti-bacterial products in general, including hand sanitizers, could contribute to antibiotic resistance. After all, they’re non-selectively killing bacteria on the surface your skin. Although scientists continue to debate this idea, there’s little solid evidence, at this point, that hand sanitizers contribute to antibiotic resistance. Studies carried out so far show no increase in antibiotic resistance with hand sanitizers. That should be reassuring if you use hand sanitizers regularly.
What about Hand Washing?
Grandma was right! Hand washing is a tried and true way to remove a variety of germs, and proper hand washing ranks up there with hand sanitizers as a way of eradicating influenza viruses. However, most people don’t wash their hands well enough to reduce their risk of infection. To be effective, wash your hands for a full 20 seconds and use a towel to turn off the water to avoid re-contaminating your hands. Not sure how long 20 seconds is? Sing the Happy Birthday song slowly through one time as you scrub your hands with vigor. That should be enough to do the job.
The Bottom Line
Hand sanitizers that contain an alcohol content of at least 60% effectively kill influenza viruses when you use them regularly. However, the U.S. Centers for Disease Control and Prevention says it’s debatable whether hand sanitizers work better than washing your hands thoroughly with plain soap and water. Plus, hand sanitizers don’t remove dirt and other debris from your hands as soap and water does. Possibly the best approach is to wash your hands for 20 plus seconds as often as you can and keep hand sanitizer on hand for times when you can’t get to a sink and running water.
Also, get into the habit of not putting your fingers and hands on your face as this is an easy way to transmit viruses. During flu season, don’t underestimate the importance of other commonsense measures such as getting enough sleep, eating a healthy diet, and staying active without overtraining. A healthy immune system is the best defense against influenza and other viruses as well. Lack of sleep, malnutrition, and overtraining can all suppress immune function and increase susceptibility to the flu while moderate exercise appears to boost immune health. Keep surfaces clean too! Influenza viruses can live for up to 24 hours on surfaces and inanimate objects. Taking a few precautions could mean the difference between being out of commission for a week or staying healthy during flu season.
Oxford Academic. “Does Hand Hygiene Reduce Influenza Transmission?”
Centers for Disease Control and Prevention. “Show Me the Science – When & How to Use Hand Sanitizer”
Rush.edu. “Are Hand Sanitizers Actually Harmful?”
U.S. Food and Drug Administration. “FDA issues final rule on safety and effectiveness of antibacterial soaps”
NHS Choices. “How long do bacteria and viruses live outside the body?”