Why Did 5000 Chickens Almost Cross the Road?

Remember avian influenza? The deadly version of flu that passes from poultry to humans and has caused outbreaks in many nations, most notably China. While we were dealing with Ebola panic and now a severe seasonal influenza outbreak, these viruses continued to spread (despite the lack of headlines).

The latest version of avian influenza to generate concern is H7N9 which has infected about 500 people since March of 2013, killing one-third. Taiwan has had 4 imported cases. The virus is spread to humans through direct and indirect contact with poultry. Limited human-to-human spread may also occur.

Because of the connection with poultry, control measures are centered around delimiting exposure to potentially infected birds. This often involves closing markets, culling, and inspections. 

An ongoing dilemma in Hong Kong involved a plan to inspect all local chickens at a small checkpoint while the market is disinfected after a culling of close to 20000 birds because of the potential for H7N9's presence given imports from a mainland farm tested positive for the virus. This arrangement was not found to the liking of the farmers who believe it will prove too onerous for them to conduct business.

Their response was to threaten to release 5000 live chickens into the busiest streets of Hong Kong. Not only would that action cause a major calamity but if any of the birds are harboring H7N9 (or other avian influenza viruses that can infect humans) could potentially widen exposure which is traditionally restricted to market-goers. They have since rescinded the threat. 

This incident illustrates why infectious diseases are so important. In just this one snapshot, you see economics, commerce, trade, government, and healthcare all intermingled. The ripple effect of certain infectious disease can be far-reaching and touch on virtually all aspects of modern civilization. 

Sir William Osler once remarked that to know syphilis--which has the ability to cause disease in every organ system--is to know medicine; similarly, to know infectious disease is to know the world.

Consumption: A Disease For All Seasons, not Just a Winter's Tale

We often talk colloquially about a disease consuming an individual. Examples include AIDS, cancer, or, quite literally flesh-eating bacteria. However, there is one disease that actually has the original claim to that moniker: tuberculosis. 

Consumption was the name of the condition that eventually became known as tuberculosis and its first mentions reach back to the times of Hippocrates and Herodotus. Indeed the Hippocratic corpus distinctively describes consumption (phthisis in Greek) as being nearly always fatal and consisting of symptoms recognizable to a physician practicing over 2000 years later. The disease, in an era without antibiotics and proper nutrition, could be a death sentence and as the infection progress patients would literally waste away as the disease consumed them.

In the developed world, tuberculosis has faded from the mind of the general public and in the US we are now at an all time low with cases falling below 10,000 with 65% of cases occurring in those born outside the US--a statistic often misused by anti-immigration advocates. Because certain types of tuberculosis are transmitted from person-to-person through the air it is one of the instances in which legitimate quarantine orders are issued in the US for non-compliant patients.

A recent movie--in which I had to suspend disbelief about a flying horse, cessation of aging, and Lucifer--reminded me that anti-immigration sentiment over tuberculosis is nothing new. In the supernatural film Winter's Tale a couple arriving in late 19th century America is summarily deported when a "pulmonary" problem is detected on their screening immigration physical examination and later in the film a character dies of it. The pulmonary problem was tuberculosis.

If one reads historical accounts of how immigration and infectious diseases interacted--such as Howard Markel's When Germs Travel--you will learn that fear of tuberculosis led to a very unscientific process of looking for and excluding those with a physical appearance thought to be conducive to tuberculosis infection--ignoring the fact that the disease had stricken many individuals including the famous and the beautiful.

Tuberculosis was, for a time, the reigning king of infectious disease killers before being replaced by HIV and it has not lost its appetite for blood. Now armed with drug resistance genes, tuberculosis control will remain an important task for the foreseeable future.

HIV: You're Still the One

Infectious disease physicians often tell those who are diagnosed with HIV in the modern era that they will likely live a normal life span if they are placed on and are adherent to antiretroviral therapy. My career started just as this modern era dawned but I wasn't too far removed from the bad old days of HIV to not have some experience with it. 

As a resident, I recall about a dozen patients with undiagnosed HIV presenting to the hospital with shortness of breath and subsequently diagnosed with Pneumocystis pneumonia. Some of these patients ended up in the ICU and on mechanical ventilator. During my fellowship in infectious disease, by contrast, I think I only saw one relatively mild case of Pneumocystis. 

A few weeks ago, however, I had the unfortunate opportunity to relive this experience when a patient was admitted to the hospital with a severe pneumonia requiring mechanical ventilation and round-the-clock care in the ICU. This patient was not known to be HIV positive but I soon discovered that the virus and Pneumocystis were responsible for the dire conditions of the patient. 

According to current statistics, 86% of those with HIV know their status leaving 14% unaware of their diagnosis. My patient was one of the 14%. Being aware of one's diagnosis is no guarantee, however, that viral suppression will occur. In fact, 70% of those with HIV in the US have not achieved viral suppression, despite the high potency of antiretroviral therapy indicated other factors are at play. 

Individuals with Pneumocystis pneumonia who require a ventilator have a 60% mortality rate--a startlingly high mortality rate that often necessitates starting anti-HIV therapy in the ICU without counseling, without a genotype, and with no assurance that the patient will be compliant. But, in such situations anything that will help the patient leave the hospital alive is welcomed. 

My patient, thankfully, was one of the 40% that survive but served to remind me that in the midst of Ebola, MERS, and avian influenza, HIV remains an ominous foe.

What Do Vibrators & Sepsis Have in Common?

Answer: The movie Hysteria and very little else (but exceptions unfortunately exist). 

I can't resist commenting on mentions of infectious diseases in popular media. As I've written before, these mentions often give a snapshot of how the general public views a particular topic whether it is HIV, Ebola, or influenza.

Hysteria is a somewhat fictional account of the invention of the vibrator in 19th century England as well aa a critique of the diagnosing of hysteria--a nebulous term that, when applied to a woman, horrifically could led to a hysterectomy for no reason. The film accurately depicts hysteria as akin to blood-letting, leeches (which do have a few legitimate medicinal uses), and the "laudable pus" that emanated from infected wounds.

In the movie Dr. Mortimer Granville, the real inventor of the vibrator, is portrayed as an innovative, evidence-based, and modern physician railing against treatments that are ineffective or do harm. In one of the opening scenes, Dr. Granville has an important exchange with a nurse instructing her to remove dirty bandages from wounds because of the risk of sepsis, a word derived from the Greek term for "to make rotten".

As an infectious disease and critical care medicine physician, sepsis--a systemic inflammatory state induced by infection with microorganisms--is something I can't avoid seeing upon setting foot in the hospital but the concept was completely foreign to medicine until the germ theory was developed and accepted. No embrace of antisepsis and sterility could really occur if there was no realization that microbes could cause disease. "I don't think I have those," the patient in the scene remarks and indeed it would be impossible for a person without the context of the germ theory to imagine invisible organisms as being responsible for a state of disease.

The senior physician remarks that "germ theory is poppycock" to which Dr. Granville retorts "Lister has proved it."

Today that microorganism can cause disease is not even greeting with disbelief from children, who rush to have Band-Aids applied to the slightest abrasion. In the end, germ theory--the development of which I hope to write a lot more about--was not poppycock but the result of the synthesis and integration of many facts by the likes of Lister, Pasteur, Koch, Semmelweis, Leeuwenhoek, and others. 

This small vignette from a movie largely unrelated to the topic gives a brief glimpse into what those heroic individuals had to overcome in order to usher in an era of vaccines, antibiotics, the entire medical speciality of infectious diseases, and ever increasing life spans.

"Venereal" Musings on The Theory of Everything

"Is it venereal?" 

That was the question posed to Stephen Hawking in the movie The Theory of Everything  by his roommate after Hawking states he has been diagnosed with a disease as portrayed in the movie  As is common knowledge, Professor Hawking has waged an odds-defying battle with the debilitating Lou Gehrig's Disease (ALS)--something definitely not venereal--while at the same time building an astonishingly productive career devoted to contemplating the widest of possible abstractions.

But, in a weird coincidence (or maybe I'm just stretching this) Hawking's work has something in common with venereal matters. The concept venereal derives from the Roman term for the goddess of love and beauty, Venus, whose name was given to the brightest object in the sky (excluding the sun and the moon): the 2nd planet from the sun. Diseases that arose while pursuing "love" were, therefore, named for the patron goddess of love.

My favorite fact about Professor Hawking that isn't widely known is that his father Dr. Frank Hawking was an expert in parasitic infectious diseases such as malaria, trypanosomiasis, and filariasis and headed the parasitology branch of the UK's National Institute for Medical Research. I think it must've been incredible to hear dinner conversations in which one person is talking about microscopic organisms and the other massive black holes and stars.

I found the movie was in many ways inspirational as it explicitly endorsed the idea that there is no limit to human endeavor and did not shy away from Professor Hawking's atheism.

One quote in particular I found very illuminating was: "A physicist can't allow his calculations to be muddled by belief in a supernatural creator." I think it is a broadly applicable piece of advice that applies to all endeavors and instructs us that reality, the knowledge of which is pursued through the faculty of reason, is the ultimate arbiter of the veracity of our work. Any consideration that undercuts that standard will muddle one's thinking because it involves placing something above one's reasoning mind.

With a poetic license of sorts, I take venereal to be reaching for the brightest stars in the skies--a goal we all should strive for.