[intro music] (host) Why do you wash your hands And did you know the first physician who said doctors need to wash their hands was put into an insane asylum?

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If someone walked out of the bathroom without washing their hands, then tried to give you a high five, I'm pretty sure you wouldn't be so eager to make physical contact, especially in the middle of flu season.

But until relatively recently, hand-washing was something relegated primarily to religious rituals and cultural ceremonies.

And the story of how we came to wash our hands as a central part of hygiene is a fascinating exploration of how people can be threatened by new knowledge.

But to understand how we got to side-eyeing people who don't wash their hands in the restroom, we first have to ask: What types of hand washing existed before it became a form of germ control?

Well, it turns out that the expression in English of "washing your hands of something or someone" to signify that you are removing yourself from a situation or absolving yourself of responsibility for an outcome originates in the Bible.

In the New Testament Book of Matthew, Pilate pours water on his hands to symbolize that he is innocent of a crime, which is where the popular idiom draws its roots from.

And as a ceremonial practice, hand-washing plays an important role in Judaism, Islam, and Sikhism.

For example, in Islam, ritual cleansing of the body is essential before prayer.

Ablution, known as wudu, includes washing the hands, face, feet, and other parts of the body in preparation for spiritual ceremony.

And this occurs five times a day, outside of other hand-washing and bathing routines.

So the hand-washing here is connected to cleanliness and cleaning the body, but also carries a larger spiritual meaning.

And in Judaism, it's customary for people to wash their hands and say a blessing before eating a meal that includes bread or matzo.

This is known as the netilat yadayim, and it is also performed outside of hand-washing that occurs to keep dirt away because it is related to a larger spiritual context.

Other forms of ritual hand-washing can exist even after death.

Take for example Buddhism.

Before cremation, pouring water over the hands of a dead body can be essential to a sign of forgiveness.

And during the new year, a younger person washing the hands of an elder can also be a sign of wishing them a long and healthy life.

So, hand-washing was clearly on the scene as religious metaphor before we connected it to health, but that brings us to our next question: When did we connect hand-washing to disease prevention, and who made that first connection?

Well, according to Rebecca Davis at NPR, we owe that revelation to a Hungarian physician named Dr. Ignaz Semmelweis, though, at the time, no one really believed him.

In 1846, this young obstetrician was interested in figuring out the connection between physicians' cleanliness and the spread of puerperal fever, also known as childbed fever.

But, at this time, germ theory wasn't commonly accepted as scientific fact, so physicians often focused on many different, and primarily false, causes of diseases, such as bad spirits, misaligned humors, and individual disposition.

Despite this, Semmelweis and other physician scientists were interested in making connections between anatomy and disease and collecting data to prove patterns rather than asserting that disease was entirely unique to the individual.

In particular, Semmelweis was invested in reducing deaths from puerperal fever, so he studied two maternity wards-- one staffed by male physicians and another staffed by female midwives.

He noticed that mothers in the clinic staffed by physicians died more frequently from childbed fever.

At first, he postulated that it was because the mothers in the doctors' ward gave birth on their backs, and the mothers in the midwives' ward gave birth on their sides.

But when he tried shifting the positions of the women in the physicians' ward, he saw no change.

Then one of the pathologists he worked with died of puerperal fever after pricking his finger performing an autopsy, which was kind of eye-opening to him because he discovered that anyone exposed to the disease could die, and not just women who had given birth.

Semmelweis then theorized that the real difference was that the physicians were performing autopsies on patients who had died from the disease, while the midwives were not.

And he thought that the physicians were transferring little pieces of corpse to women in childbirth, which was killing them as a result.

Although not technically correct, it's actually very impressive that he was able to deduce this considering he didn't know what germs even were.

So Semmelweis made the interns in his clinic wash their hands and instruments with chlorinated lime solutions.

As a result, fatal puerperal fever was reduced from an average of 10% to 1-2%.

So, hurray for the hand-washing Hungarian doctor, right?

Well, actually no.

Semmelweis's contemporaries didn't take kindly to his findings because they thought, one, he was a quack bigger than Donald Duck, and two, he was making it look like they were responsible for killing their patients by passing on tiny bits of corpse during childbirth.

So, he lost his job and was shunned by the medical community, even as he spent the rest of his life trying to convert other doctors to scrub up with chlorine before touching patients, which would have saved countless lives.

He wrote a series of increasingly scathing letters, and in 1865, at age 47, he was committed to a mental asylum because of his hand-washing crusade and a suspicion that he was losing his mind either from some form of Alzheimer's or syphilis, and he died there only 14 days later at the age of 47 after being beaten by the guards.

But scientists such as French biologist Louis Pasteur eventually did develop theories around bacteria control.

He found that heating up, then cooling down foods, such as milk, wine, and beer, could kill some of the creepy, crawly bacteria that caused most spoilage, and he later went on to develop vaccines for anthrax and rabies by expanding his germ theories.

And Florence Nightingale also championed hand-washing in hospitals during the Crimean War to reduce the spread of infections.

But, as for washing your hands after you go number 1 and number 2, it wasn't until the 1980s that the CDC in the U.S. started to advertise regular campaigns to promote hand-washing after a rash of food-borne outbreaks and healthcare-related infections.

After that, they developed and promoted guidelines for proper hand hygiene.

So, how does it all add up?

While hand-washing has been around for hundreds of years as parts of different rituals, ceremonies, and every-day hygiene, it wasn't until the latter half of the 19th century that we started to think of it as a central form of keeping illness at bay.

And the first physician to start championing hand-washing as a central part of disease control was committed to an asylum and eventually beaten to death where he died of suspected sepsis, which, ironically, is a disease that hand-washing and proper hygiene could have prevented.

Wow, this really is kind of cruel.

Today, the Centers for Disease Control and Prevention, or the CDC, and the World Health Organization advocate that all health-care providers and patients should keep those hands clean in order to prevent the spread of different illnesses, and both institutions are invested in conducting research on how to spread awareness about hand-washing practices across cultural considerations.

But, if you're feeling bad for Dr. Semmelweis's sad demise, there is a small footnote to add.

Just like Pasteur, whose name lives on in the word "pasteurization," there is something named after his lesser-known contemporary.

The Semmelweis Reflex, or Semmelweis Effect, is the term for rejecting new ideas, knowledge, and findings, simply because they don't conform to current norms.

So, if history has a sense of humor, it's very dark and extremely morbid.

So, what do you think?

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