Expertise

The attitude of many laypeople toward medical science can be summed up as "all you have to do is."

Never mind those silly experts, who actually went to medical school and all.  All you have to do is (choose one or more):

• take vitamins (two favorites are C and D)
• spend more time outdoors
• get more exercise
• get more exposure to sunshine
• drink more water
• stop eating meat
• eat more probiotics
• eat more protein
• eat less protein
• eat less processed food
• eat less sugar
• eat less salt
• eat less, period

Now, mind you, I'm not saying these are bad ideas, with the exception of eating both more and less protein, which are hard to do at the same time.  Most of us could use more exercise and eating less sugar and salt, for example.  It's just that the "all you have to do is" attitude tries to boil down all medical conditions to some easily understandable, easily treated set of causes, and avoids the scary truth that human health is complicated.

Sometimes so complicated that even the experts are stumped.

One of the weirdest examples of that latter phenomenon is a ten-year-long epidemic that happened in the early twentieth century, which directly caused at least a half a million deaths worldwide, and that even so most people haven't heard of.  It's called encephalitis lethargica, but that's really only a description of its symptoms; encephalitis means "brain swelling," and lethargica -- well, that one's obvious.  The first cases in the epidemic (although as you'll see, perhaps not the first cases ever) happened in 1915, and just about all of the patients experienced the same, very odd progression of symptoms:

• first, sore throat, headache, and lethargy
• double vision and an uncontrollable upward motion of the eyes ("oculogyric crisis") 
• upper body weakness, spasms, and neck rigidity
• "sleep inversion" -- the drive to sleep during the day and be awake at night
• temper tantrums, psychosis, and hypersexuality
• "klazomania" -- compulsive screaming
• catatonia

The most commonly effected were males between the ages of five and eighteen, but people of all genders and ages could (and did) get the disease.  The mortality rate was high -- about half of the known victims died within a year of onset -- and of the ones who survived, a great many had neurological problems for the rest of their lives, with many of them exhibiting emotional disturbances and/or Parkinsonism.

The disease is sometimes called Economo's disease, after Austrian neurologist Constantin von Economo,  who along with French pathologist Jean-René Cruchet wrote several papers describing the pathology, symptoms, and treatments (the latter, mostly unsuccessful) for it.

Medical journal photographs from 1920, showing Constantin von Economo (upper left) along with four patients suffering from encephalitis lethargica [Image is in the Public Domain]

To cut to the punch line: we still have no idea what caused it.

Initially, it was thought to have something to do with the Spanish flu, which happened around the same time -- possibly an autoimmune reaction triggered by the flu virus -- but that hypothesis was ruled out because there seems to be no correlation between the disease and previous flu exposure.  Also, the Spanish flu pandemic ended in 1919, while the epidemic of encephalitis lethargica went on until 1926.  (This by itself doesn't eliminate a connection; odd immune reactions occurring long after exposure are relatively common, such as shingles turning up years after contracting, and recovering from, chicken pox.)  The brilliant writer Oliver Sacks, in his book Awakenings, stated that the most likely culprit was an enterovirus, a group that contains the causative pathogen of another multi-symptom disease -- polio -- as well as the Coxsackie viruses, thought to play a role in such autoimmune diseases as type 1 diabetes, myalgic encephalomyelitis, and Sjögren's syndrome.  This contention, however, is still considered speculative at best.

While the 1915-1926 outbreak was the most serious, medical historians have identified other epidemics that may be encephalitis lethargica in Europe -- 1580, 1674, 1712, and 1890.  Because there's no certainty of the cause of the 1915 outbreak, it's hard to be sure these are the same disease, but from the symptoms they sound similar.

The reason I bring all this up today is more than just a chance to talk about a biological oddity.  It's to point out that human physiology, and all the things that can go wrong with it, are complex topics.  Emergent diseases like encephalitis lethargica are scary precisely because they strike suddenly and hard, then can vanish before we have much of a chance to study them (and potentially prevent subsequent outbreaks).

And -- the crucial point -- when they do, we need the best-trained minds in medical science to have every tool at their disposal.

Which, in the United States, we don't.  At the moment, the head of the Department of Health and Human Services is a loony anti-vaxxer who is still trying to connect vaccines to autism despite massive study after massive study showing there's no correlation, much less a causation.  His latest salvo was touting putting cane sugar back into Coke as a major victory in "Making America Healthy Again," despite the fact that it's hard for me to see how anything involving drinking Coke would foster better health.  There's a real concern that because of his policies we may have significant shortages of the flu and COVID-19 vaccines this fall, raising the specter of unchecked epidemics.  Research into cancer treatment -- including an mRNA vaccine that shows great promise in treating deadly pancreatic cancer -- have had their funding pulled.

Oh, but according to RFK Jr., that's not a problem.  "All you have to do" to remain healthy is spend more time outdoors and take vitamins.

This is the man in charge of our health policy today.

Look, I know all too well that there were serious problems with the American medical system even before RFK was appointed.  Overpresciption of antibiotics, opioids, antidepressants, and anxiolytics.  Necessary medical procedures being denied by avaricious insurance companies.  Getting the runaround from GP to specialist and back again, with the result that treatment can be delayed weeks to months.  My wife's a registered nurse; don't think I'm unaware of the issues.

But.  If I were to develop a serious medical condition, I'd still want trained experts working on it.  Why on earth would I not?  How does it make sense to doubt medical expertise, when we trust expertise of just about every other sort?  No one gets on an airplane and says, "To hell with training, I'm okay if the plane is piloted by a plumber who has never flown before."  When your house's wiring needs work, you don't say, "I'm fine hiring an accountant to do the job.  He'll do just as well as an actual electrician."  People of all professions work long and hard to acquire their skills and knowledge, and by and large, we trust that they know what they're doing within their given fields.

So why have we been told that medical researchers are somehow the only ones who are lying to us?  And why do so many believe it?

I wish I knew the answer to that.  Maybe it's just because with something as complex and potentially scary as our health, we tend to flail around for something, anything, to make it simpler and more reassuring.  And it's a sad truth of life that sometimes the answers evade even the experts.  The outbreak of encephalitis lethargica is just one of many examples.  But when the next mystery disease strikes -- or even some of the familiar ones -- we want the best shot we have to respond quickly and effectively.

And for that, we need trained doctors and researchers, not anti-science ideologues.

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The mystery plague

Ever heard of cocoliztli?

In one way, it's shocking if you haven't, and in another, hardly surprising at all, because the vast majority of its victims were the indigenous people of Mexico and Central America, and history has a way of ignoring what happened to brown-skinned people.  Cocoliztli is the Nahuatl name for a contagious, usually fatal disease that struck Mesoamerica repeatedly, with the worst recorded outbreaks in the sixteenth century, killing an estimated ten million people.  This puts it in fifth place for the worst pandemics known, after the Black Death (estimated one hundred million casualties), Justinian's plague (fifty million), HIV/AIDS (forty million), and the Spanish flu (thirty million).  [Nota bene: if we're adding up total death toll, one of the worst is smallpox, but as that was endemic and widespread, I'm not counting that as a true pandemic.  In eighteenth-century Europe, for example, it's estimated that four hundred thousand people died of smallpox per year; and its introduction into the Americas decimated Native populations.  It's likely we'll never know for sure how big the death toll was, but it was huge.]

The symptoms of cocoliztli were awful.  Severe headache, high fever, vertigo, jaundice, and abdominal cramps.  The worst was the hemorrhaging -- victims bled from every orifice including the tear ducts.  Most of the victims died, usually between four and seven days after onset.

[Image is in the Public Domain]

There are two curious things about cocoliztli.  The first is that there hasn't been a confirmed case of it since 1813.

So where has it gone?  Ordinarily, infectious diseases occur at low rates until a confluence of events triggers a more widespread outbreak.  Consider, for example, the Black Death.  Bubonic plague (caused by the bacteria Yersinia pestis) has been present in humans for millennia, but a perfect storm occurred in the mid-fourteenth century that caused the most devastating pandemic in history.  First, it was the beginning of the Little Ice Age, and the lower temperatures drove rats (and the fleas they carried) indoors, and into contact with humans.  Second, trade throughout Europe, and with Asia (via the Silk Road), had really just started to gear up, and rats are notorious for stowing away on ships.  And third, the population had risen -- and larger, more crowded cities facilitate disease spread.

Cocoliztli, though, hit Mesoamerica hard, and seemingly out of nowhere.  Repeated outbreaks in 1545, 1576, 1736, and 1813 killed millions, but in between, we don't know where it went -- or why after 1813 it apparently vanished completely.

The second odd thing is that we still don't know what caused it.

The bones of presumed victims have offered up only debatable information.  Back in 2018, Johannes Krause, of the Max Planck Institute for the Science of Human History, found DNA in bones from victims of the 1545 outbreak that seems to come from a Salmonella enterica strain called Paratyphi C, but that doesn't mean that's what killed them -- and one epidemiologist has pointed out that typhoid fever, which is caused by S. enterica, doesn't have the same symptoms as cocoliztli.  Others suggest that its symptoms are more consistent with a viral hemorrhagic fever like Ebola, Lassa, and Marburg, but there are no viruses known that are endemic to the Americas and cause symptoms like that.

A rather sobering possibility is that the pathogen, whatever it is, resides in an animal vector -- that is, it's a zöonotic disease, one that exists in an animal population and is reintroduced to humans periodically upon contact.  If so, it's unknown what that vector might be -- but the jungles of Central America are a big place, and there are lots of animals there in which a pathogen might hide.

Whatever causes it, and wherever it went, it's to be hoped it's gone for good.  This would put it in the same class as the mysterious European sweating sickness, that caused repeated outbreaks in the late fifteenth and early sixteenth centuries, and then vanished, apparently permanently.  It, like cocoliztli, was highly infectious -- but the pathogen remains unidentified.

Cocoliztli left its mark on history.  The population of Mexico collapsed in the sixteenth century, largely due to the outbreaks, dropping from an estimated twenty-two million in 1500 to two million a hundred years later.  This undoubtedly contributed to the Spanish takeover -- something that reverberates to the present day.

It's also an enduring mystery.  How such a virulent disease could strike so hard, decimating an entire region, and then vanish utterly is bizarre.  But it does highlight how important epidemiological research is -- helping us to understand how pathogens cause disease, and how they jump from one host to the other.  Giving us, it is to be hoped, the tools for stopping the next pandemic before it happens.

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Replacement coffee

Commercial farmers of perennial crops have an inherent problem.

The cheapest, most efficient, and most cost-effective method of growing something where the roots (or the entire plant) persists from year to year -- which includes fruits, nuts, and tropical products like coffee and cacao -- is to plant a large quantity of a single variety of plant.  The difficulty is that the plants are therefore closely related genetically, if they're not out-and-out clones, and susceptible to the same pests and diseases.  It's what did in the Irish potato farmers during the 1840s and 1850s; late blight (Phytophthora infestans) wiped out the single-variety potato crop five years running, resulting in the Great Famine in which a million people starved to death and another two million left Ireland for good, one of the largest exoduses from a single country in the history of humanity.

This is increasingly the situation being faced by the people who raise bananas.  Virtually all the bananas produced commercially are a single variety -- the Cavendish banana -- all descended from root cuttings of a plant from Mauritius that was in the greenhouse of the Duke of Devonshire.  Those cuttings were sent first to Samoa and other islands in the South Pacific, and thereafter to the Canary Islands, West Africa, and South and Central America, where the variety was found to be resistant to a fungal infection called Panama disease that had wiped out the previous main cultivar ("Gros Michel"). 

The problem is -- as we're seeing from COVID-19 -- pathogens have a way of staying one step ahead of us, and now there's a strain of Panama disease that kills Cavendish bananas.  Unfortunately for those of us who, like myself, love bananas, there is no obvious next strain to turn to.

The other plant in a similarly dire situation is -- and I hate to bring this up -- cacao.  Chocolate producers are fighting an increasingly long list of pests and diseases that target cacao plants, which are notoriously fragile and easy to kill.  As with banana growers, there is no good option for cacao farmers other than to fight the pathogens and insects when they show up and hope for the best.

Hearteningly, the situation is a little better with another of the world's most beloved crops, which is coffee.  

[Image licensed under the Creative Commons Julius Schorzman, A small cup of coffee, CC BY-SA 2.0]

In fact, this is the reason why the topic comes up; an article in Nature a couple of weeks ago looks at a different species of coffee (Coffea liberica) that shows real promise in avoiding some of the difficulties of growing the two main varieties, arabica (Coffea arabica) and robusta (Coffea canephora), which make up (respectively) about 55% and 45% of the commercial coffee in production.  The plants have better heat and humidity tolerance, and good resistance to coffee leaf rust and coffee wilt disease.  Liberica coffee (often called "excelsa" in the trade) was initially discounted because of the quality of coffee it produced, but that seems to be because the larger seeds have to be processed a little differently or they lose a lot of their flavor.  Dealt with correctly, liberica coffee has (according to the writers):

...a mild, smooth, pleasant-flavoured coffee of low to medium acidity and low bitterness, as per historical accounts.  Tasting notes include cocoa nibs, peanut butter, dried fruits, Demerara sugar and maple syrup; and for samples from South Sudan, there are notes of raspberry coulis, figs, plums and milk chocolate.

All of which is awesome but a little mystifying to me.  You probably know that there are people called "supertasters," who have a far greater acuity in their senses of taste than average, and who can pick out all the delicate nuances of taste in things like coffee, chocolate, wine, and so on.  I, on the other hand, am the opposite.  I'm a stuportaster.  I have two taste buds, "thumbs up" and "thumbs down."  Presented with most cups of coffee, my response is "coffee good, want more."  (The rest of the time my response is "coffee bad, no thanks.")  I do the same thing with wine, much to the dismay of the sommeliers when we visit wineries, who love nothing more than blathering on about the wine's nose and flavors and notes and finish, and do not appreciate a dolt like me who pretty much just drinks it and looks around for a refill.  So while I'm glad there's someone around who can pick out notes of Demerara sugar and raspberry coulis in their morning cup of coffee, for me it kind of starts and ends with "me like it lots."

In any case, it's encouraging that the coffee farmers may be able to escape dire situation being faced by owners of banana and cacao farms.  It's bad enough facing the prospects of losing two of them; losing all three would just be catastrophic, even for people like me who only have two taste buds.

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A commerce in death

My novella We All Fall Down is set during some of the most awful years humanity has ever lived through -- the middle of the fourteenth century, when by some estimates between a third and half of the people in Eurasia died of the bubonic plague, or as they called it, the "Black Death."

Back then, of course, no one knew what caused it.  Not only that the disease came from a microscopic organism, but that it was carried by fleas and spread by the rats that carried them.  The superstition of the time meant that people became desperate to find out why this catastrophe had occurred, and the blame was placed on everything from God's wrath to evil magic by witches, warlocks, and (unfortunately for them), the Jews.

It's natural enough to try to figure out ultimate causes, I suppose, even though they can be elusive.  I tried to express this in words of the narrator of We All Fall Down, the young, intelligent, inquisitive guardsman Nick Calladine, who has found himself entangled in a situation completely beyond his comprehension:

I asked Meg if she would be all right alone, and she said she would.  There were one or two other villagers who had survived the plague, and they were helping each other, and for now had enough to eat.  I wondered what would happen when winter came, but I suppose that their plight was no different from that of many in England.  Some would make it, some would not, and that was the way of things.  We are not given to understand much, we poor mortals.  The religious say that after we die we will understand everything, and see the reasons that are dark to us now, but I wonder.  From what I have seen, things simply happen because they happen, and there is no more pattern in the world than in the path a fluttering leaf takes on the wind.  To say so would be considered heresy, I suppose, but so it has always seemed to me.

The proximal cause of the Black Death -- rats, fleas, and the bacterium Yersinia pestis -- doesn't explain why the disease suddenly caught hold and exploded its way through the population.  One of the more plausible explanations I've heard is that climatic changes were the root cause; the Northern Hemisphere was at the time in the beginning of the "Little Ice Age," and the colder, harsher weather caused crop failure and a general shortage of food.  This not only weakened the famine-struck humans, but it drove rats indoors -- and into contact with people.

Seventeenth-century "plague panel" from Augsburg, Germany, hung on the doors of houses to act as a talisman to ward off illness [Image is in the Public Domain]

The reason all this dark stuff comes up is that a new study, by a team led by Maria Spyrou of the Eberhard Karls University of Tübingen and the Max Planck Institute, has added another piece to the puzzle.  Using a genetic analysis of bones from a cemetery in Kyrgyzstan, which lay beneath a stone whose inscription indicated they'd died of the plague, Spyrou et al. found that not only did the DNA from remnants of Y. pestis in the bones match those of European plague victims, it matched extant reservoirs of the bacteria in animals from the nearby Tian Shan Mountains.

The authors write:

The onset of the Black Death has been conventionally associated with outbreaks that occurred around the Black Sea region in 1346, eight years after the Kara-Djigach epidemic [that killed the people whose bones were analyzed in the study].  At present, the exact means through which Y. pestis reached western Eurasia are unknown, primarily due to large pre-existing uncertainties around the historical and ecological contexts of this process.  Previous research suggested that both warfare and/or trade networks were some of the main contributors in the spread of Y. pestis.  Yet, related studies have so far either focused on military expeditions that were arguably unrelated to initial outbreaks or others that occurred long before the mid-fourteenth century.  Moreover, even though preliminary analyses exist to support an involvement of Eurasian-wide trade routes in the spread of the disease, their systematic exploration has so far been conducted only for restricted areas of western Eurasia.  The placement of the Kara-Djigach settlement in proximity to trans-Asian networks, as well as the diverse toponymic evidence and artefacts identified at the site, lend support to scenarios implicating trade in Y. pestis dissemination.

So it looks like the traders using routes along the Silk Road, the main conduit for commerce between Europe and East Asia, may have brought along more than expensive goods for their unwitting customers.

Scary stuff.  I hasten to add that although Yersinia pestis is still endemic in wild animal populations, not only in remote places like Tian Shan but in Africa (there have been recent outbreaks in Madagascar and the Democratic Republic of Congo) and the southwestern United States/northern Mexico, it is now treatable with antibiotics if caught early enough.  So unlike the viral disease epidemics we're currently fighting, at least we have a weapon against this one once you've contracted it, and it's unlikely to wreak the havoc now that it did in the past.

At least we are no longer in the situation of horrified bewilderment that people like Nick Calladine were, as they watched their world shattering right before their eyes.  "My father was one of the first to take ill, in July, when the plague came, and he was dead the same day," Nick says.  "My sister sickened and died two days later, her throat swollen with the black marks that some have said are the devil’s handprints.  They were two of the first, but it didn’t end there.  In three weeks nearly the whole village of Ashbourne was dead, and I left alive to wonder at how quickly things change, and to think about the message in Father Jerome’s last sermon, that the plague was the hand of God striking down the wicked.  I wonder if he thought about his words as he lay dying himself at sundown of the following day."

Although we still don't have the entire causal sequence figured out, we've come a long way from attributing disease to God's wrath.  With Spyrou et al.'s new research, we've added another link to the chain -- identifying the origins of a disease that within ten years, had exploded out of its home in Central Asia to kill millions, and change the course of history forever.

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Risk and brain amoebas

We humans are poor at assessing risk.

It's something I've commented upon before; we tend to vastly overestimate the likelihood of being harmed by something gruesome and unusual (such as a shark attack), while vastly underestimate the likelihood of being harmed by something commonplace (such as smoking).  This leads to missed opportunities and unnecessary anxiety in the first case, and ignoring truly dangerous behaviors in the second.

This comes up because of an article I've seen posted now several times, about an Ohio teenager who died from an infection by the "brain-eating amoeba" Naegleria fowleri.  The 18-year-old victim appears to have been infected while on a whitewater rafting trip near Charlotte, North Carolina, and several days later came down with the fever, chills, and headache associated with primary amoebic meningioencephalitis, which is as horrifying as it sounds.  The microorganism gets into your system through inhaled water, and it travels through the olfactory nerves to the brain.  There it turns from eating its usual food source, bacterial films in freshwater sediments, to consuming your brain cells.  The disease has a 97% mortality rate.

Naegleria fowleri [image courtesy of the CDC]

Unfortunately, the story (although correctly reported, for the most part) is inducing widespread hysteria from people who evidently missed the following line: "The CDC reported 37 infections in the 10 years from 2006 to 2015."  Let me put that statistic a different way; given the current population of the United States (318 million), that amounts to about one death per hundred million people per year.  Even if there were three times as many cases that go unreported -- unlikely, given the severity of the symptoms and the likelihood of dying as a result -- it's still a tiny, tiny risk.

Interestingly, these numbers are ten times smaller than the likelihood of your being crushed to death by a piece of your own furniture (303 deaths in the last ten years).

So here are a few of the comments I've seen posted in the last couple of days, edited to reflect the far more likely scenario of your being killed by a falling television cabinet.  I've inserted "television watching" and equivalent phrases for "swimming" and "hard hat" for "nose plug."

• I wish I hadn't read about this!!!  I'm never sitting in front of an unsecured television cabinet again.
• Just in time for summer.  So much for television watching.
• They should post warning signs on television cabinets!  It could have prevented this tragedy.
• Every time I'm sitting in front of the television, I'm gonna think about this.
• I'm protecting my kids from this.  They'll never watch television again without wearing a hard hat.

There.  I hope that sounded as ridiculous to you as it did to me.  And remember; there is ten times the justification for making those statements as there is for making equivalent statements about brain-eating amoebas.

Note that I'm not trying to minimize the tragedy of what happened.  A young life cut short is always sad, especially given how unlikely an occurrence it was.  What is completely unjustified is the panic that these sorts of stories always induce, even in people who should know better.  The U.S. National Whitewater Center, where the young woman is thought to have been infected, has responded by hyperchlorinating their well water, and health officials in North Carolina have recommended "holding your head above water when taking part in warm freshwater activities" and "avoid(ing) water-related activities in warm freshwater during periods of high water temperature and low water levels."

So when are you supposed to go swimming?  January?

The bottom line is that everything you do is a risk.  Most of the risks are quite small, and chances are that you do several things every day without a thought that are orders of magnitude riskier than your being killed by brain amoebas.  If you really want to lower your risk of illness and death, quit smoking, eat a healthy diet, drive carefully, find ways to reduce your stress levels, and get enough exercise.

And keep an eye on any unsecured television cabinets.  They're just waiting for an opportunity to strike.