Handwashing 101

AMID the fog of war around Severe Acute Respiratory Syndrome, with all the confusing and often contradicting news and advice, you'll find SARS experts are unanimous about one of the most effective ways to fight SARS: handwashing with soap and water.

In this high-tech age, it's difficult to believe that something as simple as handwashing can be so effective against disease and death. Yet this procedure actually had to be "discovered," and it remains one of the most important milestones in the development of modern medicine.

What led to handwashing as a medical practice? Western medicine developed around hospitals, where patients were put in close contact with each other. This meant diseases could actually spread faster in these institutions.

The spread of germs wasn't just among patients. As several physicians discovered, many of the infections were actually "iatrogenic," a fancy term which means "caused by the doctor."

The story of one of those physicians who "discovered" handwashing is particularly interesting. In 1847, a young doctor named Ignaz Semmelweis was teaching surgery and obstetrics in a Viennese hospital and observed that most of their surgery patients were dying. Moreover, in an obstetrics section handled by medical students, one out of every six mothers died after child delivery. The high maternal death rate was a source of embarrassment because in another section of the hospital, where deliveries were handled by midwifery students, the death rate was 2 percent. The medical ward became so notorious that women coming in to deliver their babies would kneel and beg to be handled by the midwifery students.

Semmelweis investigated, and realized that medical students and doctors were spreading infections around because they would move from patient to patient without washing their hands. Another deadly trail involved doctors moving from autopsies of cadavers in the hospital morgue to living patients, with the doctors doing nothing more than wiping their hands on their coats to remove dirt.

After Semmelweis introduced handwashing with chlorinated lime, the death rates for surgery patients and mothers dropped.

Around this time, physicians in other parts of the world -- Oliver Wendell Holmes in the United States, Thomas Watson in London -- also urged handwashing in hospitals but were ridiculed for their recommendations. It was only in the 1860s, after germs were proven to exist, that handwashing became a required procedure in hospitals.

Today we know that handwashing can also save lives outside of hospitals. It's our hands that allow us to pick up germs, as we touch people infected with diarrheal diseases, colds, flu, SARS or a host of other sicknesses, or objects contaminated with the germs. We then bring our germ-infested hands to our mouth, nose or eyes, all portals of entry for the germs.

Handwashing is simple but for it to be effective against germs, there's both science and art involved. Let's look at what's entailed.

It's worth repeating a quote I used last week from the World Health Organization (WHO)'s Laboratory Biosafety Manual, which gives advice to people working in medical laboratories, places with high exposure to disease-causing germs: "In most situations, thorough washing of hands with ordinary soap and water is sufficient to decontaminate them...Hands should be thoroughly lathered with soap, using friction, for at least 10 seconds, rinsed in clean water and dried using a clean paper or cloth towel (if available, warm-air hand-dryers are also recommended)."

Running water washes off many of the germs but in addition, we will need soap, and ordinary ones will suffice against many types of germs. The SARS virus is especially vulnerable because it is surrounded by a lipid or fatty envelope which soap breaks down, thus killing the virus.

The advice for thorough lathering and the use of friction -- also known as plain old scrubbing--is to bring up the dirt and debris, together with the germs, before you wash them out. Note the 10-second advice is a minimum -- you could go longer but don't get too obsessed here. (I'm imagining Lady Macbeth's handwringing.)

The WHO manual suggests using a warm-air hand-dryer because then you don't come in contact with other new sources of germs after you've washed your hands. Cloth hand towels shared by different guests and visitors can actually be dangerous, helping the germs to move from one person to another. It's safer to use paper towels. If you feel this violates your environmental conservationist instincts, then bring your own clean towel or handkerchief. If you're throwing a party at home, have a roll of paper towel or a stack of face towels, one for each guest. The towels can be boiled and reused afterwards.

I've also seen public health advisories reminding people not to touch any part of the sink or the faucet handle after you've washed your hands. The sink's easy to avoid but what about the faucet? You have three alternatives here. First there are those high-tech sensor faucets which automatically turn on and off in response to the hands' movements but these are expensive. A second alternative is to use a paper towel to turn the faucet on and off. The last alternative, which you can perform with flair, is to imitate health professionals by using your elbows to manipulate the tap. (Okay, I can hear you asking now, what if your elbows end up contaminated? Really now, do you ever bring your elbows to your mouth, nose or eyes?)

Some health education materials also recommend liquid soap over soap bars because the latter end up being handled by more people. Liquid soap stays inside the container until it's squirted out.

Proper handwashing isn't all that complicated, but it does entail some practice. Start with the kids so the 10-second scrubbing and lathering becomes an enjoyable game, and then a habit. Getting older people to learn proper handwashing may be more difficult, with all kinds of excuses: no soap, no water, no time. We have to keep reminding ourselves this 10-second routine is one of the most cost-effective prevention measures against disease, maybe even death.