# 4402
Last summer and fall many people adopted – at least temporarily – increased hand washing (and alcohol sanitation) as a preventative against the H1N1 `swine’ flu.
Hand hygiene was widely promoted by the CDC, and other public health venues, as something everyone could do to reduce their chance of getting sick.
As a compulsive hand-washer (a trait I picked up as a paramedic back in the 1970s, a time before we routinely wore latex gloves!), my habits didn’t really change, although I probably used the alcohol gel more often when I was away from home.
But for many people this habit, unlike the germs on their hands, didn’t stick.
With the swine flu threat widely perceived as diminishing, people don’t seem to be quite as diligent about hand hygiene as they were a few months ago.
A pity, because good hand hygiene can prevent a lot of illnesses.
New England Journal of Medicine
Maryn McKenna had a great blog more than a year ago (see This is what hand hygiene looks like), utilizing the above graphic. The petri dish on the left depicts MRSA bacteria from a health care worker’s hand.
The blank culture on the right is what you get after using alcohol foam sanitizer.
Good hand hygiene matters.
In recent weeks we’ve heard of a rise in Norovirus outbreaks (see Norovirus: The Gift That Keeps On Giving) around the country.
The primary route of infection is the fecal-oral route (although it can also be airborne), and the best intervention is . . . you guessed it . . . washing your hands.
Unfortunately, unlike with many other bacteria and viruses, alcohol gel doesn’t do a particularly good job of killing the norovirus.
(Note: Norwalk and Norovirus both refer to the same RNA virus (family Caliciviridae) that that are responsible for numerous outbreaks of non-bacterial gastroenteritis around the world.)
Appl Environ Microbiol. 2010 Jan;76(2):394-9. Epub 2009 Nov 20.
Effectiveness of liquid soap and hand sanitizer against Norwalk virus on contaminated hands.
Liu P, Yuen Y, Hsiao HM, Jaykus LA, Moe C.
(EXCERPTS)
The purpose of this study was to screen sodium hypochlorite and ethanol for efficacy against Norwalk virus (NV) and expand the studies to evaluate the efficacy of antibacterial liquid soap and alcohol-based hand sanitizer for the inactivation of NV on human finger pads.
. . . sodium hypochlorite concentrations of >or=160 ppm effectively eliminated RT-qPCR detection signal, while ethanol, regardless of concentration, was relatively ineffective . . .
Despite the promise of alcohol-based sanitizers for the control of pathogen transmission, they may be relatively ineffective against the HuNoV, reinforcing the need to develop and evaluate new products against this important group of viruses.
When dealing with Norovirus, hand washing with soap and water is clearly the way to go.
While the effectiveness of hand washing against what is presumed to be a mostly-airborne/large droplet vectored virus like influenza is debatable, good hand hygiene can prevent a lot of other illnesses.
Pandemic or not, it is always a healthy habit to keep.
