Sunday, February 12, 2012

A disease spread by doctors

(I just noticed that I'm jumping between posts on slow cooking pork shoulder to posts on "cadaverous particles." This makes for an appetizing blog)


This is a post about a disease spread by doctors, the doctor who discovered how it happened, and the doctors who didn't believe him.

Childbed fever (also known as puerperal fever) is a bacteria infection of the uterus contracted during the birth of a child, an abortion, or miscarriage.  It can be deadly – if untreated, it can spread into the bloodstream and cause septicaemia (blood poisoning), which can kill in a matter of hours.

It was common in mid-19th century hospitals and was often fatal, with mortality rates ranging from 10% - 35% (which is 1 in 3 women!).  Nobody quite knew the cause of the sickness, just that it seemed to happen most often when it was a doctor who was handling the procedure. Incidences of childbed fever were low when it was a midwife delivering the baby, and almost nonexistent when the woman delivered the baby on her own – even if it was on the streets.

Streptococcus pyogenes (red-stained spheres) is responsible for most cases of severe puerperal fever.  Credit: Encylopedia Brittanica

In Europe during that time, maternity institutions were set up to address problems of infanticide of illegitimate children (making them a popular service for prostitutes). They'd offer their services for free; in return, these women would be subjects for training of doctors and midwives.

There were two such institutions at well-respected Vienna General Hospital. The First Obstetrical Clinic, which served as a training ground for medical students, had an average mortality rate of 10%, whereas the Second Clinic, which trained midwife students, had a drastically lower mortality rate of 4%.

A young Hungarian doctor, Ignaz Semmelweis, was appointed the chief resident of the First Clinic in 1846.  He was puzzled and disturbed by the number of women dying in his clinic (he'd witness women begging on their knees to be admitted to the Second Clinic).  He set out to find out the cause, first by attempting to eliminate all controllable differences between the two clinics, including medical technique and even religious practices.

Dr. Ignaz Semmelweiss

In 1847, Semmelweiss had his breakthrough.  That year, a colleague of his was accidentally poked by a student's scalpel during a postmortem examination and died. Semmelweiss, noting that his colleague had suffered the same symptoms as childbed fever prior to his death, diligently studied autopsy reports and discovered more similarities between his colleague's death and those of the women in the maternity clinics.

He concluded that somehow "cadaverous particles" had made their way from the corpses to the medical equipment to the hands of the students and eventually the uteruses of the women in the birthing wards.  In the mornings, the medical students would often go to the "Dead House," where they'd perform autopsies on women who had died the night before, wipe their hands on towels, and then head over to the clinics to take up duties as obstetricians in training.

This explained why there was a much lower mortality rate in women helped by student midwives, who were not engaged in autopsies.

These "cadaverous particles" were invisible – the only telltale sign of their presence was a putrid odor.  Semmelweiss figured if he could get rid of the smell, he could get rid of the particles.  He thus subjected all students to submerge their hands in a chlorine wash before seeing patients.  In six months, the mortality rate of childbed fever plummeted, eventually reaching zero in the year following his discovery.

Microbial growth on a blood agar plate without any procedure (sector A), after washing hands (sector B), and after disinfecting hands with alcohol (sector C). Credit

He published articles on his findings, but despite his success at Vienna General hospital, his theories on handwashing and cleanliness were largely rejected by the medical community.  Some doctors were offended at the suggestion that their hands were unclean – "Doctors are gentlemen, and gentlemen’s hands are clean." And remember, this was the time when diseases were thought to be caused by an imbalance of the basic "four humours" in the body, for which the main treatment was bloodletting.

Ultimately, Semmelweiss was unable to offer acceptable scientific explanations for his findings. In 1849, he was forced to leave his post at Vienna General Hospital and eventually, left Vienna altogether.  He began to suffer from several depression, attack his critics (which further undermined his professional credibility); there are also reports that he turned every conversation to the topic of childbed fever.

In 1865, he was commited to an insane asylum, where he was severely beaten by guards and set up with a straitjacket and a dark cell. He died two weeks later from (ironically) septicemia.

Well, he got a stamp 100 years after he died.

His practice only earned widespread acceptance years after his death, when Louis Pasteur confirmed the germ theory.  Now, the "Semmelweiss reflex" describes the reflex to reject new knowledge because it contracts established norms or beliefs.