Creutzfeldt-Jakob

Painting by Eric Sloane

Lito Souza is a Brazilian aviation mechanic and enthusiast who for years has discussed aviation safety and the joys of flying online. One of the first videos of Lito that I watched was of him dissecting an accident that marked not only my life, but the lives of many people in Brazil and around the world: the crash of Air France flight 447 that left Rio de Janeiro and was on route to Paris in 2009, which killed 228 people in the Atlantic Ocean. Incidentally, since I'm afraid of flying, Brazilian air disasters, or those connected to Brazil in some way, have always been very significant for me. Before Air France flight 447, there was TAM flight 3054, which veered off the runway at Congonhas Airport in São Paulo, coming from Porto Alegre, killing 199 people. Less than a year before the TAM accident, there was the horrific Gol flight 1907 accident, in which 154 people died, the result of a Boeing colliding with a private jet that was making idiotic mistakes in Brazilian airspace with the approval of a problematic air traffic control system. And, for those of us who are older, the most significant accident of the 1990s: the crash of the TAM Fokker 100 in 1996, which went down shortly after taking off from Congonhas bound for Rio and killed 96 people.

I watched Lito talking about all these accidents and many others, but I also watched him talking about aircraft safety; I saw his fascination with the world of commercial aviation. It was with great sadness that, on the evening of Friday, August 21st, I learned that he had been diagnosed with Creutzfeldt-Jakob disease. Creutzfeldt-Jakob disease is one of the prion diseases. Prion is an English term formed from the words "proteinaceous infectious particle." Normally, proteins fold in a certain way inside the bodies of humans and other animals. Still, in some mammals, including humans, a rare event can occur in which a single specific protein misfolds in the nervous system. This may seem harmless, but it is a complete disaster, because the protein causes a chain reaction in which other proteins in contact also misfold, forming insoluble buildups that destroy neurons.

The result of this process is the death of the brain, which takes on the appearance of a sponge when observed during autopsy. This is why prion diseases such as Creutzfeldt-Jakob disease are also known as spongiform encephalopathies. The symptoms are loss of motor and cognitive functions. That is, the patient can no longer move and develops dementia. All this occurs within months of the first symptoms. The incubation period, however, varies between individuals and between types of prion diseases. Prion diseases also affect goats, sheep, deer, felines, and cattle. And it can be transmitted through the consumption of meat contaminated by prions. This is how the best-known type of outbreak happened. I'm referring to mad cow disease. What happened in England in the late 1980s and 1990s was this: several cattle ranchers, to cut costs, began feeding their livestock with feed that included ground-up brains from dead cattle. At some point, a bovine animal developed sporadic prion disease, and its brain was ground up and distributed to be transformed into feed.

The cattle that ate this feed were then contaminated by prions. In turn, some of them died and were fed back into the system. The contaminated beef also reached British butcher shops. Several people were infected and died. The British outbreak killed 178 people, the last of whom died in 2016, with an incubation period longer than average. In the 1950s, in Papua New Guinea, scientists began observing a disease called "kuru" by the Fore people. The symptoms are very similar to those of other spongiform encephalopathies, and in fact, the brains of people who died from kuru had a spongy appearance. The Fore people had a funerary custom of eating the flesh of the deceased, particularly the brain tissue. After many years, symptoms appeared, and people died shortly afterward. Scientists then convinced them to change the ritual and stop consuming the flesh. Cases began to drop drastically. The conclusion was that, many decades before 1950, someone died of a random prion disease. This person was then consumed by the tribe, and the cycle began.

Yet, despite these cases of transmission like mad cow disease and kuru, most cases of prion diseases around the world remain random. There was also the case of a French scientist, named Émilie Jaumain, who accidentally pricked her finger with a needle while working with mice infected with prions. This occurred in 2010. Years later she developed the first symptoms and, in 2019, died. But this is an even rarer case than random occurrences and cases involving the consumption of human or bovine flesh. Spongiform encephalopathies of all types are rare and unfortunate diseases. There is another type of prion disease that, unlike others, is transmissible to offspring: fatal familial insomnia. It is even rarer, and death occurs after many months of complete inability to sleep. There is a total cessation of sleep, which does not come even with general anesthesia. Without sleep, the person's brain stops functioning properly, they begin to hallucinate, lose motor control, develop dementia, and die.

Amyotrophic lateral sclerosis (ALS) and Alzheimer's disease, although not prion diseases, are often called prion-like diseases because of their inexorable progression related to misfolded proteins, a progression that ends in the destruction of important functions that keep us alive: motor functions in the case of ALS and cognitive functions in the case of Alzheimer's. However, they occur due to proteins different from the protein that causes prion diseases, such as kuru, mad cow disease, Creutzfeldt-Jakob disease, and fatal familial insomnia. All these diseases combined don't even come close to the mortality rate caused by cardiovascular diseases and neoplasms, that is, the various types of cancer. If we remove Alzheimer's and other common dementias, if we leave only ALS and prion diseases, the situation becomes even more abysmal. The rarity is absurd; less than 0.01% of the population is affected annually. ALS itself, despite being rare, manages to be 10 to 20 times more common than all prion diseases combined.

This is why there is much more funding for ALS research than for prion diseases, much more funding for Alzheimer's research than for ALS, and much more real progress in the treatment of cardiovascular diseases and cancers in general than in the case of these other diseases. When we differentiate between tumors, the pattern repeats itself: rarer and more deadly tumors are less researched than others that, although also deadly when left untreated, are more common and less difficult to combat. This is not a condemnation of research, it's simply reality. One thing we need to remember, however, is that despite the rarity of prion diseases and prion-like diseases, millions of people are affected by them, especially if we include Alzheimer's. Even if we don't include Alzheimer's, tens and even hundreds of thousands of people are affected annually, people who suffer terribly and die horribly.

When my cousin Juliana died of glioblastoma multiforme three years ago, I wrote about how some diseases are "miracle killers," because they are so terrible that we don't see charlatans selling miraculous cures through faith. This remains just as true today. No amount of faith in the universe can alter the course of spongiform encephalopathy, ALS, or glioblastoma multiforme. Only science, perhaps one day, will be able to. And even then, it's uncertain. With treatment, glioblastoma kills in just over a year, on average. Without treatment, the average lifespan is less than six months. My cousin underwent treatment and died seven months after the first symptom. Despite all the progress we've made and despite all the talk about us building machines supposedly endowed with divine powers, we can't even cure common tumors when they, unfortunately, spread to the bones. Bone metastasis from a curable primary cancer is still almost a death sentence in many cases, if not in most cases, despite all the advances made by medical science. This is not a criticism of science. But there are insurmountable limits. We are indeed ephemeral beings. And we will never be gods.

My heart goes out to Lito and his family.

by Fernando Olszewski