Hand sanitizer is regulated by the Food and Drug Administration (FDA) as an Over The Counter (OTC) item which by law are required to have an expiration date and lot number. Hand sanitizers have an expiration date on their bottle just like toothpaste does. Feb 08, 2013 Hand sanitizers have a form of alcohol, such as ethyl alcohol, as an active ingredient. It works as an antiseptic. Other ingredients may include water, fragrance, and glycerin. Which bugs can hand.
By Jenny Hall, University of Toronto
Everywhere you turn of late, it seems you’re confronted with a bottle of alcohol-based hand sanitizer. We asked Professor James Scott whether these formulations work—and if so, how?
Professor James Scott is an associate professor in the Division of Occupational & Environmental Health at the Dalla Lana School of Public Health. He is cross-appointed to the Department of Medicine, Division of Clinical Pharmacology and Toxicology, and holds hospital appointments at St. Michael’s Hospital and the Hospital for Sick Kids. We originally spoke to him in the fall of 2009. This is an updated version of our original interview, reflecting some new research on the topic.
Does hand sanitizer work?
I was one of the skeptics. But as I have looked critically at the research that has come out, I can say yes, it really works. It works exceedingly well for most bacteria and viruses. It reduces the skin burden of bacteria much more effectively than soap and water and the amount of bacteria on the skin tends to remain lower for much longer than when soap and water is used. It also tends to be less damaging to skin because it has built-in emollients. People who are in occupations where there is a lot of hand washing, have skin that tends to dry out easily and it can crack and become more prone to carrying bacteria. Hand sanitizer doesn’t replace soap and water if your hands are dirty, but along with regular hand washing, it definitely helps fight many important germs.
How does it work?
It works by killing cells—not human cells. It kills microbial cells. It’s based on the use of 70 per cent isopropanol alcohol, which is rubbing alcohol. That’s the concentration of rubbing alcohol that is most effective in killing germs—it’s even more effective than 100 per cent. Because it has a little bit of water in it, it improves penetration. For a virus, sanitizers work by disrupting the virus’s outer coat. For a bacterium, they work by disrupting its cell membrane. It is not a panacea, though, since certain viruses lacking an outer coat (like the one that causes cruise ship diarrhea) or spore forming bacteria (like C.difficle) are not very susceptible.
Some people say that using hand sanitizer is bad because it prevents us from building up natural resistance to bugs.
Show me the evidence.
Physicians used to tell their patients if they didn’t want their kids to be allergic to cats, then don’t have a cat. Physicians have told their patients this for the last 50 years. Now there’s growing evidence that if you have the cat, you might actually have some protection against allergies. What you’re saying is a similar idea. But the reality is we just don’t have that information. There’s no evidence to support it one way or another.
So for things like H1N1 you recommend people use hand sanitizer.
This is the absolute best front-line protection for those kinds of diseases. These products appear to be a highly effective part of flu control programs.
Is it only colds and flus that hand sanitizers fight?
They work on a range of bacterial and viral illness. Depending on what the agent is, it may be more or less tolerant or susceptible to hand sanitizers, but for most of the things that people need to worry about in day-to-day life—upper respiratory infections, gastrointestinal infections, those kinds of things—most agents that cause those diseases are highly susceptible to modern hand sanitizers.
What about health care workers? How much does our health depend on them using these products?
In occupations where there’s a lot of human contact there’s the potential for the practitioner to act as an intermediary, transferring germs from one patient to the next. Anything that’s effective and increases the compliance of the practitioner in going through the motions of infection control and prevention is helpful.
There have always been difficulties with compliance, getting health care workers to wash hands on a sufficiently frequent basis, between patients and between tasks. Compliance was always difficult because handwashing is often inconvenient and takes time. The introduction of hand sanitizers improved hand hygiene tremendously, not only because it was so effective, but it was also easier and faster than regular handwashing. It’s really helped in terms of reducing germ transmission. It’s often cited as an example of an improved infection control measure that is a runaway success on all fronts.
So you’re not a skeptic any longer.
No. In the past several years, as I’ve seen evidence build up, I’ve ceased to be a skeptic. This stuff really does work. I doubted it, but it works.
Provided by University of Toronto
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Friends, if you’ve managed so far to avoid catching the particularly nasty strain of norovirus that’s going around this winter, I salute you. Sincerely. Norovirus — also known as winter vomiting virus or plain old stomach flu — is going around with a vengeance and it has health workers and parents struggling to keep up. Not only does the bug pass quickly through unsuspecting classrooms, it takes the cleaning equivalent of dynamite to get rid of it. Ok, that last part might have been an exaggeration, but not by much. But it turns out the one thing that most parents keep in their germ-fighting arsenal is of zero use when it comes to stopping the stomach flu. Why won’t most hand sanitizers kill norovirus? Because norovirus is the absolute worst, that’s why.
Here’s the thing about norovirus: it’s spread by coming in contact with fecal matter. That means it spreads in laundry, in food touched by poorly washed hands, and even in the air when a toilet is flushed. It also means that proper hand washing is the most effective means of staying healthy, according to the Centers for Disease Control. The problem is that most people don’t wash their hands well enough to kill norovirus.
So, it would seem that using a strong, alcohol-based hand sanitizer might offer an extra bit of insurance, right? Especially for those of us with little ones still learning how to properly scrub their hands. Not this time.
Traditional hand sanitizer doesn’t work on norovirus because of the bug’s unique structure, according to an NBC News report. Each particle is surrounded by a protein-based shell called a capsid. The capsid helps the virus stay alive on surfaces and avoid getting dried out. It also forms a protective layer that alcohol just can’t get through.
'It's resistant to many common disinfectants,” said Dr. Aron Hall, CDC’s norovirus expert, in an interview with NBC. “It can persist on surfaces for several days, even at room temperature.” So, when cleaning after sick people in a school or home, it’s important to use cleansers strong enough to do more than just wipe the particles away. To kill norovirus — and avoid accidentally infecting others days or even weeks down the line — requires a stronger agent like bleach or hydrogen peroxide, according to that report. There are a few types of hand sanitizer that kill norovirus, and they have an anti-microbial called benzethonium chloride in them.
Still, the CDC’s best advice for handwashing to avoid norovirus is simple: use regular soap and hot water, but do it for at least 30 seconds, scrub hard, and be sure to get under those nails. Diligence is important because even a few particles of norovirus can lead to a full-blown case of vomiting.
I said it from the beginning: norovirus is the absolute worst. Stay healthy, friends.