Can an ancient disease cancel a Phish concert?

TeachableMedicalNews article 03052020

Teachable moment in classrooms:

1. cellular basis of life chapter – endocytosis as cellular transport
2. immune system chapter – phagocytosis by the cells of the innate immune system
3. immune system chapter – activation of the B cells by macrophages in the adaptive immune system
4. immune system chapter – antibodies speed up phagocytosis of invading microbes
5. microbiology —  pathology of Yersinia pestis bacterium

The news item:  Recently the disease called plague was reported to disrupt camping and other preparation for a Phish concert in Denver:

Plague-ridden prairie dogs force cancellation of Phish camping event

This is probably not what Phish had in mind when they wrote their 1994 single, “Down with Disease.” Self-proclaimed “Phans” of the legendary jam band are singing the blues a…

The article mentioned that prairie dogs were infected with the plague, and there was concern that the plague would be passed on to concert goers.

So, Why Do I Care??  The disease called bubonic plague, caused by the plague bacterium, killed 25 million people between the 14^th and 18^th centuries.  There were devastating outbreaks in Africa and China as well.  So, this is a very potent, lethal bacterium.  While antibiotics can save the lives of infected individuals, infection could spread country-wide throughout the concert goers, and the news of a country-wide outbreak could wreak havoc in the lives of millions of people.

Plain English, Please!!! First, let’s talk about the plague itself.  The disease has very dramatic symptoms of having large nodules (the bubos) in the groin and armpit areas; there is a dark splotchy rash on the skin, and the person may cough up or vomit blood.  Death comes within one to six days after infection.  No wonder the plague is called Black Death.  So, why doesn’t our immune system destroy this deadly bacterium? Why don’t our white blood cells and our antibodies protect us?

Second, let’s talk about immune defense against bacterial invaders.  Many aspects of our immune system rely on white blood cells ingesting and digesting (in other words, phagocytosing) microbes.  The plague bacterium is very good at disabling that phagocytosing process.  When someone turns off the main electrical switch for your house, all appliances shut down.  Turning phagocytosis disables many immune defense functions in our bodies.  Turning off phagocytosis first disables the immediate ingestion and digestion of bacterium in the body, so plague bacterium escapes digestion.  Next, the bacterium disables the macrophages whose phagocytosing activity activates the antibody making cells.  As a result, the invaders are not marked for destruction.  The third effect is to disable the phagocytosis that removes bacteria marked by antibodies, so even if our immune system can pinpoint plague bacteria in the body, the digestion is prevented.

Third, let’s talk about prairie dogs spreading the plague bacterium.  The Phish concert eventually wasn’t canceled, but camping was prohibited in an area frequented by prairie dogs.  The plague doesn’t spread through the bite of the prairie dog, but rather through the bite of fleas living on the prairie dogs.  So, the closing of the camping area was done to make sure concert goers are not bit by the fleas from the plague carrier prairie dogs.