Hand Sanitizers vs. Soap + Water

I need to preface this post with two points:

One: This post is for Sarah.

Two: As a touchy and somewhat contentious subject, I am only going to present the facts.  Yes, I have an opinion and I will offer it at the end under the heading of “my opinion, “ but everything leading up to that will be fact.

                With the threat of swine and avian flu tumbling through our winter lives, I noticed an increase in Purell hand sanitizer stations.  They became pervasive in my last work establishment and probably had been a permanent fixture in my new workplace for several years.  I remember watching people religiously rubbing the gel all over their hands after touching door handles or their fellow workmates.   I’ve also noticed an increase in toilet seat covers, women leaving restrooms holding paper towels and pre-rolling paper towels from the machines before washing hands.  However, in sharp contrast, I also still see women putting a lot of soap on their hands, then turning on ice cold water and doing only a cursory wash job.  I still laugh at the complete juxtaposition of these two characterizations.  (I'm not trying to be down on women, by the way.  I'm a girl and, as such, hang out in women's bathrooms - that's all).

                Why is hand washing so important?

                The Center for Disease Control (CDC) urges everyone to wash their hands appropriately several times a day to help prevent the spread of disease.  The importance of hand washing has been well established, but I will elaborate this point with one particular example.

                Childbed fever, known in the medical world as puerperal fever, is a serious infection contracted by women following childbirth.  If left untreated, this bacterium will cause septicemia and eventual death.  In my mind, the most famous historical death due to puerperal fever was Jane Seymour, third wife of Henry VIII.  She died twelve days following the birth of Henry’s most cherished and longed for son, the future Edward VI.  

                In 1847, Dr. Ignac Semmelweis concluded that hand washing was integral to the spread of puerperal fever.  This was the era before antibiotics and where women commonly delivered at home.  One percent of women who delivered at home died of childbed fever; an astonishing 20% died in hospitals.  Why?  Dr. Semmelweis agonized over the differences and finally said it was hospital doctors spreading infection from patient to patient.  After demanding that each doctor and nurse extensively wash their hands with chlorine between patients, the maternal death rate dropped to 1% in his Vienna hospital.  (Honestly, the area of birth is quite interesting to me as is the medical profession in general.  I highly recommend the book “Complications” by Atul Gawande, as well as “Better” by Atul Gawande and “Birth” by Tina Cassidy.  Both “Better” and “Birth” detail the history of childbed fever.) 

                Currently, the world offers two choices for hand washing: soap + running water or hand sanitizers.  In my previous post Soap!, I discussed how soap works.  Bacteria and viruses use hydrophobic molecules to envelope their cytosols (The Central Dogma) and genetic material (DNA/RNA).  Soap, which has a hydrophic end, can work itself into those protective hydrophobic coats of bacteria and viruses to break them open.  Once opened, the soap molecules can then find their way to bacterial/viral proteins and start to disrupt their structures.  After the soap has done those two jobs, placing your hands under running water allows those broken viruses and bacteria to be washed down the drain.

                Hand sanitizers work similarly in that ethanol or isopropanol (the active ingredient in hand sanitizers, which must be in excess of 60%) will also disrupt bacterial membranes, break open the bacteria and destroy protein structures.  There is no running water in this case so hand sanitizers merely disinfect hands, but do not clean them.

                The CDC recommendations for hand washing can be found here: http://www.cdc.gov/handwashing/

                In short, they say this:

One: If you have clean running water available, use soap and the running water to wash your hands.

Two: if you have running water that isn’t necessarily clean, use soap and the available running water to wash your hands.

Three: If you have no running water, use hand sanitizers.  (Remember, hand sanitizers do not clean hands – they merely disinfect them.)

                I recently read a paper about hand sanitizers versus the human norovirus.  Noroviruses notoriously infect cruise ship passengers and well meaning people during winter to cause bouts of diarrhea and vomiting (my worst nightmare, folks).  Oddly, hand sanitizers are not effective against noroviruses or similarly nonenveloped enteric viruses.  Further work needs to be done to find hand sanitizers effective against these agents.

My Opinion

                Wash your hands with old fashioned soap and water.  It’s wonderful and effective.  The CDC even recommends hand washing in this fashion over hand sanitizers and – in my impression after reading - that hand sanitizers should really be used in conjunction with regular hand washing, not in place of.  I do believe that hand sanitizers have their place, but I will always defer to frequent soap and water.  

I realize that doctors and nurses, who quickly jump from patient to patient, do no share this luxury and a fast squirt from a Purell to disinfect is easiest and best for patients before moving on.

Yes, Purell will help coworkers minimize transfer of infection to each other when in a work place environment – absolutely.  But, if my experience in bathrooms is saying anything, people need to learn how to wash their hands properly, as well.  Read the CDC guidelines.  Washing your hands isn’t running them under water and isn’t just covering them with soap.  Spend 20 seconds really washing and massaging your hands, between fingers and under your nails.  Spend a few extra seconds really rinsing your hands under running water and using clean paper towels to dry off.  

Stay healthy!

Septicemia: presence of bacteria in the blood

Non-enveloped enteric viruses:  viruses that infect the intestines that do not have hydrophobic coats for protection

REFERENCES

http://www.cdc.gov/handwashing/

http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0002331/

Weir, Alison. "The Six Wives of Henry VIII."  (1991) The Bodley Head, London, England.

 

Liu et al. “Effectiveness of Liquid Soap and Hand Sanitizer against Norwalk Virus on Contaminated Hands.” (2010) Applied and Environmental Microbiology 76(2), pgs 394 – 399.

Gawande, Atul. “Better: A Surgeon’s Notes on Performance” (2007) Picador, New York, New York.

Cassidy, Tina. “Birth: The Surprising History of How We are Born.” (2006) Grove/Atantic Inc. New York, New York.