Which hand sanitizers kill stomach flu viruses (especially norovirus)?
Two problems with finding a good hand sanitizer
1. The FDA is a problem. The FDA won't let hand sanitizer companies tell you what specific viruses or bacteria that a hand sanitizer kills. Many hand sanitizers test their products for their ability to kill norovirus surrogates and other illness causing germs. However, the FDA won't let them tell us the results. Cleaning products are allowed to list the germs they kill on the package. But hand sanitizers are not allowed. Zylast, one of my long-time favorite hand sanitizers got in big trouble with the FDA because they showed people, including me, their norovirus test results. I think it is ridiculous that the FDA doesn't think people deserve to have this information.
1. It has been difficult to test on human norovirus. It has been very difficult to test hand sanitizers and cleaning products on human norovirus, because human norovirus has refused to grow in the research lab. Human norovirus loves to attack cells inside people, but does not want to infect human cells in a petri dish. So, products that have been tested on human norovirus have looked at specific features, for example, if the viral capsid protein was damaged after treatment with this hand sanitizer or not? They have never been able to look at the end result, can the norovirus still infect cells after treatment with this hand sanitizer. Most products have been tested on norovirus surrogates. These are similar viruses, such as feline calicivirus and murine norovirus, which are able to infect cells in a petri dish. However, we can't be absolutely certain that a product that kills these surrogates would really kill human norovirus.
There is hope, though! Thanks to Dr. Mary Estes, there has been a breakthrough in growing norovirus in a lab. So maybe soon products will be able to be tested on the real human norovirus. Until then, all I can do is give my best recommendations based on the data for products killing norovirus surrogates. Here are the hand sanitizers that I have been using that have been tested against norovirus surrogates. There may be other hand sanitizers that kill norovirus but they haven't been tested or won't release the results. I, however, can only recommend a hand sanitizer that HAS been tested and shown to kill a norovirus surrogate AND the company would give me the test information.
Does Alcohol kill norovirus?
There are many different norovirus strains and some are more resistant to alcohol than others. Here is a research paper that tested many strains of human norovirus against ethanol and isopropanol. Ethanol worked better than isopropanol. Some strains of norovirus seemed sensitive to ethanol and some strains seemed resistant. Here is an article explaining that it isn't just the concentration of ethanol that matters. The Norovirus surrogate was killed better by 62.4% ethanol than by 77% ethanol. The addition of acids such as malic acid can improve norovirus-killing. So, whether or not a product can kill norovirus is much more complicated than just the ethanol concentration. These tests did NOT show that after treatment with ethanol, the norovirus could or could not infect a human cell. They were just looking at whether the viral capsid proteins were damaged. Companies that sell alcohol based hand sanitizers usually say that they add other ingredients to make the ethanol more effective. We hope that is true and not just a marketing gimmick. The norovirus surrogate Feline Calicivirus is more resistant to ethanol than the other commonly used surrogate, murine norovirus.
"Stomach flu" is just a nickname for viral gastroenteritis. It is not related to influenza, the real flu.
For everyday life, vigorous hand washing is good enough to remove most of the germs. However, if you are in a public place and can't get to a sink, I would recommend using a hand sanitizer that has been tested and approved to kill norovirus. I do not recommend using regular 60-65% alcohol hand sanitizer gels such as Purell because they are likely to be ineffective against norovirus1.
Zylast Antiseptic hand sanitizer is the hand sanitizer that I use and have in my purse. It kills 99.97% of the norovirus surrogate Feline calicivirus! It is also advertised to possess some residual activity and has been shown to continue working for about 6 hours against bacteria. It was not tested for residual activity against norovirus. I have not been able to detect any residual activity in my experiments with Zylast. I use Zylast because it does really well in my experiments right when I use it. It's active ingredient is 76% ethanol. The company claims that the "Zylast Technology" makes it kill norovirus much better than ethanol alone. They also sell the Zylast Antiseptic Lotion. The company told me that the lotion has NOT BEEN tested for its ability to kill norovirus and the ingredients are different. So I recommend buying Zylast Antiseptic and NOT Zylast lotion. I tested the zylast antiseptic, and it did a great job killing bacteria when you first use it. I was unable to show that it continues to work, though. The thing I love most about Zylast antiseptic is that it kills bacteria well even on visibly dirty hands so it is a good choice for kids. You can see my experimental test results here. It is QUIETER to use compared to the sprays during church. Here is the technical information about Zylast. You can order Zylast antiseptic here.
76% ethanol, Water, Polyaminopropyl Biquanide, Panthenol, Hydroxyethyl Ethylcellulose, Farnesol, Peg-12, Dimethicone, and Benzethonium Chloride.
Zylast Antiseptic LOTION
.2% Benzethonium Chloride, Water, Alcohol Denat., Cetearyl Alcohol, Glycerin, Polyaminopropyl Biquanide, Dimethicone, Stearamidopropyl Dimethylamine, Benzyl Alcohol, Farnesol, Panthenol, Zinc gluconate, Chlorhexidine Digluconate, Citric Acid, Polyquaternium-10, and Tocopheryl Acetate.
My-Shield Hand Sanitizer
my-shield Hand Sanitizer kills the norovirus surrogate murine norovirus AND is the first hand sanitizer that I have ever heard of that kills C. Diff SPORES!!!! Clostridium difficile is a bacteria that causes a horrible intestinal infection that can last for months or years. It is very common in hospitals. If you are on an antibiotic such as clindamycin and step foot into a hospital for any procedure, you are at risk for getting C. diff. (I am not a medical doctor and there are other risk factors for contracting C. diff.) My very healthy 16 year old nephew was on clindamycin and went into the hospital for a few hours for a minor surgical procedure and caught C. diff. He was sick for 1 year. C. diff forms spores that are extremely hard to kill. Most cleaning products won't kill C. diff spores except chlorine bleach. My-shield hand sanitizer has actually been tested and shown to kill 99.99% of C. diff spores in 10 minutes. Here is the C. diff test data that the company sent me. Yes, 10 minutes is kind of long but far better than nothing. If you work at a hospital, you could put it on when you leave and the vast majority of the spores and norovirus should be dead by the time you get home. (Wash your hands when you get home anyway.) This hand sanitizer is fragrance-free, contains no alcohol, and is very gentle on hands. It is a foam composed of four quaternary ammonium compounds (.13% benzalkonium chloride, trimethyoxyl silyl propyl, trihydroxyl silyl ammonia, and polyamino biguanide). I know that there are dozens of hand sanitizers with benzalkonium chloride as the active ingredient, however, benzalkonium chloride does not kill norovirus good enough by itself to be a useful hand sanitizer. However, when combined with the other quats, the My-Shield does a great job. Here is the norovirus surrogate test data that the company gave me. The My-Shield is also advertised to continue to work for several hours after application. I don't rely on that for any hand sanitizer that advertises it. It is always best to wash hands or reapply before eating if you can. Here is the company brochure about it. I've also tested My-Shield myself on my kids' dirty hands. It did very well! You can see my results here.
Clorox Hand Sanitizing Spray
Clorox Hand Sanitizer Spray was tested and shown to kill 99.3% of the norovirus surrogate Feline Calicivirus. That is pretty good since Feline Calicivirus is very resistant to alcohol. Clorox does not advertise that this hand sanitizer kills norovirus. However, here is a link to the test data that I received from Clorox about it. This is a liquid spray hand sanitizer with 71% ethanol. It does not contain bleach. It is not available in most stores. You can order it on amazon. I have been using this hand sanitizer myself and I really like it. Like all alcohol sanitizers, it can sting if your hands have cuts on them. I have done some experiments with it myself which you can see here. This spray works the best if you use a lot and really soak your hands and then rub. It does not work well if your hands are covered in dirt. So, wipe your hands with a wipe first if they are visibly dirty and then use the spray. It does not leave a sticky film and is safe to use on kids hands.
The company Germstar® has specifically designed a hand sanitizer that kills norovirus. It is called Germstar Noro. It's active ingredient is 63% ethanol. So, how could this possibly work when the regular 62% alcohol products don't work very well? I contacted the company to find out. I read their ingredient list, read their test results, and e-mailed the scientist who did the tests. Click here and you can read the test results too. This is what I learned. Germstar®Noro contains an emollient complex that makes it work better. The phrase "emollient complex" probably sounds fishy to you (like an anti-wrinkle cream commercial). Basically, they have added some extra ingredients that make the alcohol work much better. They also did not add glycerin (which most alcohol hand gels like Purell contain). They found that the glycerin "protects" the viruses. I believe their results and I trust that Germstar®Noro does kill norovirus, especially since the scientist who tested Germstar®Noro (Dr. Syed Sattar) is one of the top researchers in the field2. It is a liquid that comes in a spray bottle. It dries really nice with no stickiness. Like all alcohol hand sanitizers, it stings my knuckles in the winter when they are dry and chapped. Therefore, I usually just put it on my palms and fingers. I don't eat with my knuckles, anyway. It is important to use a lot of the product and really soak your hands and rub, though, if you want to kill ALL the germs. I recommend getting the 2oz bottles for carrying in your purse or coat pocket. Germstar Noro is available on amazon!
The company Germ-Aside also has a very exciting hand sanitizer called Sterizar Hand Foamer. Unfortunately, it is not available in the US at this time. It is only available in the UK. This hand sanitizer promises not only to kill norovirus but also claims to continue working for 6 hours! I have read their experimental procedures and test results and am very impressed. 6 hours after application, the test subjects who used the hand sanitizer had 99% less bacteria on their hands than the control people who did not use the hand sanitizer. Here is a link to all of their test results. It takes forever to download so be patient. When reading hand sanitizer test results it is important to understand what "log" means. Test results always talk about "log reduction". A log reduction of 5, means that the product kills 99.999% of germs. A log reduction of 4, means that it kills 99.99% of germs. A log reduction of 3 means that it kills 99.9% of germs. A log reduction of 2 means that the product kills 99% of germs. A log reduction of 1 means that the product kills 90% of germs. Without this information, it is difficult to understand the test results.
Does Purell Advanced kill norovirus?
I contacted the makers of Purell on March 8, 2012 and Oct. 1, 2014 to see if Purell Advanced was effective against norovirus. They said that they could not provide me with any of that information. This does not mean that Purell Advanced DOESN't kill norovirus, it just means that they either haven't tested it or won't/can't release the results of the test. However, if you look at my experimental results comparing Purell Advanced to Zylast, you will see that Zylast does so much better.
Do Wet Ones Antibacterial wipes kill norovirus?
Internet rumors say that Wet Ones Anti-Bacterial Wipes kill norovirus. However, this is unproven. I contacted the Playtex® company (on January 8, 2009) who makes Wet Ones® Antibacterial wipes, and they told me that their wipes have not been tested for their ability to kill norovirus or rotavirus. The active ingredient, Benzethonium Chloride HAS recently been tested for its ability to kill norovirus and it DID NOT KILL NOROVIRUS.3 This is confusing though, because benzethonium chloride is one of the ingredients in Zylast which does a great job killing norovirus. I suspect it is the combination of the alcohol and the benzethonium chloride in Zylast that makes it good at killing norovirus. I am not sure, though. There is a related compound called benzalkonium chloride which has been shown to kill norovirus in ONE research paper but it is not contained in these wipes.4 Benzalkonium chloride is contained in many foaming hand sanitizers such as Germ-X foaming hand sanitizer and Pampers Kandoo kids hand sanitizer. However, in the research paper, it took 2 hours for the benzalkonium chloride to kill norovirus so it is very unlikely that the smaller amount contained in these hand sanitizers would kill norovirus.
The Germ-X Foaming Hand Sanitizerand the Pampers Kandoo Kids Foaming Hand Sanitizer do not CLAIM to kill norovirus. However, benalkonium chloride is the main ingredient in the new GFS bioprotect hand sanitizer that says it kills norovirus. I don't think we will get to the bottom of this until these products can be tested on the real human norovirus.
Is it safe to put hand sanitizer on a child who sucks his/her thumb?
Many people wonder if it is okay to put hand sanitizer on the hands of a child who sucks his/her thumb. Most hand sanitizers are made with ethyl alcohol (ethanol). That is the same alcohol that people drink in beer and wine. So, ingesting a small amount of ethanol is unlikely to hurt anyone. I called the Ohio poison control center about this on March 13, 2012 and the nurse told me that it was perfectly safe for a child to eat the tiny bit of ethanol based hand sanitizer that was on his/her hand. I put alcohol hand sanitizer on my daughter and try to make her wait until her hands are dry before she sucks her thumb. I can't vouch for the safety of other ingredients that may be in your particular hand sanitizer or of all the other types of hand sanitizers. However, such tiny amounts probably aren't harmful. I am not proud of this but when my youngest son was 17 months old, he ate a puff of my hair mousse, a finger full of black craft paint, desitin, a mouthful of dryer lint, and one ladybug. I called poison control each time and they said none of it would be a problem since he only ate tiny amounts. My son never got sick and was fine.
--Annie Pryor, Ph.D.