The awful power of cramps demonstrated by rabies

Imagine pain so extreme that you’d rather die of thirst. That is basically what happens with rabies. And the pain is powered by … spasms. 😬

Rabies is on my mind after a rare death from the disease in North America: “Brantford, Ontario, area child dies from rabies after contact with a bat, health official says” (CBC). Rabies is notoriously the deadliest of all viral infections, ultimately causing seizures and then paralysis before death — which is thankfully preventable with vaccination before symptoms start, but unfortunately inevitable after that.

Many tens of thousands of people die from rabies around the world every year … but there are only a few dozen confirmed examples of rabies survivors throughout history. Incredible.

An electron microscope image of a rabies virus. Rabies is caused by a number of related viruses in the Lyssavirus family. Image by Norden, a Smith-Kline Company, CC BY-SA 4.0, via Wikimedia Commons.

The disease is a morbidly fascinating demonstration of how misbehaving muscle can destroy a person. Rabies begins with spasms that define most of its spectacular and distinctive symptoms. For instance, rabies causes opisthotonus, a dramatic backward arching of the entire body, caused by spastic contraction of all the extensor muscles of the neck, trunk, and legs.

The “fear of water” (hydrophobia) and “foaming at the mouth” (just a lot of saliva) is the work of throat spasms. Any attempt to drink or swallow is so painful that the patient becomes terrified of even trying. They drool because they do not dare to swallow!

But it’s even more diabolical than that.

It’s not just drinking that hurts … it’s the thought of drinking. The spasms are caused by a violent exaggeration of the normal reflex that closes the airway to prevent inhaling fluid while swallowing. That airway-closing reflex gets much more powerful and painful and easily triggered — so easily triggered that just the idea of drinking will set it off.

And so the rabies victim is not just afraid of the consequences of actually drinking, but also by the mere suggestion of it — and that horrifying predicament creates the bizarre phenomenon of water “phobia.” The patient suffers from what is surely one of the nastiest paradoxical impulses in human experience: desperate thirst matched only by the desperation to avoid water.

This a disturbing example not only of how powerful and painful spasms can be, but how motivating pain can be — enough to veto one of the strongest physiological needs we have.

Rabies is extreme, and extremes are instructive. There are many more common, milder examples of cramp-powered pain and suffering that are still highly consequential for patients. Exactly how much common pain can be attributed to cramping is perpetually unclear … but it may be quite a lot. See Cramps, Spasms, Tremors & Twitches.