Hand Washing vs. Hand Sanitizer: Which is More Effective?

Are alcohol-based hand sanitizers better than plain soap and water for killing the flu virus and other pesky viruses that circulate during the year? When it comes to hand washing vs. hand sanitizer, it may be best to stick to soap - especially if you're worried about norovirus, a nasty virus that causes nausea, vomiting and diarrhea. Here's why.

Hand Sanitizer vs. Hand Washing: Soap May Be Better

In a recent study carried out by the Centers for Disease Control and Prevention, researchers found a greater risk of norovirus outbreak among nursing home residents and staff that used alcohol-based hand sanitizers instead of soap and water. Norovirus is resistant to alcohol-based sanitizers - and using these sanitizers in place of soapy water may actually increase the risk of a norovirus outbreak in institutional settings.

Why is hand washing better for controlling norovirus spread? Alcohol-based hand sanitizers are formulated to kill bacteria and may not be as effective at killing viruses such as norovirus. As Dr. Kennedy, deputy director of public health of Monroe County in Rochester, New York points out, hand washing uses more friction, which may dislodge the virus and send it spiraling into the sink where it can be flushed away. With alcohol-based hand sanitizers you superficially rub your hands together, which can spread the virus if the sanitizer doesn't kill it.

Soap vs. Hand Sanitizer: Not All Hand Sanitizers Are Created Equally

Not all hand sanitizers are equally effective for killing bacteria - much less viruses. Some hand sanitizers have inadequate amounts of alcohol. To be effective, an alcohol-based hand sanitizer should be formulated with at least 60% ethanol - and not all of them are.

Even when a hand sanitizer contains enough alcohol to destroy bacteria, it may not kill viruses such as norovirus. Soap and water with lots of hand friction is still best for that. Plus, alcohol-based hand sanitizers are more expensive than soap and water.

Hand Washing vs. Hand Sanitizer: The Bottom Line?

Don't be lulled into a false sense of security by hand sanitizers. They don't kill all viruses that cause infection, and not all hand sanitizers contain enough ethanol to be effective. If you don't have access to soap and water, an alcohol-based sanitizer is better than nothing - but don't use it as a substitute for hand washing.

References:

Medscape.com. "Alcohol-Based Hand Sanitizers Associated With Norovirus Outbreaks"

The New York Times. "Hand Sanitizers, Good or Bad?"