The Fever Tree
Updated: Nov 1, 2022
Last night after dinner, I curled up on the couch and started reading “The Signature of All Things” by Elizabeth Gilbert. I am not far enough into the book to give a final answer on how much I like it as a whole, but I can say that I very much like the start of it. In particular, I very much enjoyed the section on the history of the fever tree. Nope, not the fizzy drink, I mean Cinchona Chahuarguera, the tree that was the origin of the first chemical compound ever successfully used to treat an infectious disease.
As Elizabeth Gilbert quite accurately describes, historical records and legends suggest that the fever tree’s bark was used as a medication against fever by indigenous people living in the Andean jungle, where the tree originates. When Spanish colonists entered the picture, they learned about the medical potential of the fever tree’s bark from the indigenous people. In particular it was Jesuit missionaries who paid special interest to the healing power of this bark, and apparently pondered its potential for uses in other geographical areas.
This strikes me as an fantastical logical leap to assume that the bark of a tree that was probably traditionally used mainly to combat the fever and shivers that come from tramping through thick, damp forest at high altitudes, might also be a handy anti-malarial tool. But, the Spanish turned out to be correct.
After the Jesuits learned of the fever tree in the 1620s, legend goes that while visiting Peru, the Spanish countess of Chinchon was successfully treated with the dried and powdered bark of the tree after contracting a nasty fever. With her return to Spain, this “Jesuit’s Bark” was introduced to Europe in 1638. The scientific name of the tree, Cinchona Chahuarguera, is believed to have been a tip of the hat to the Countess, by the Swedish botanist who classified the tree in the 1740s.
Despite some initial hesitancy to adopt the use of the “Jesuit Powder” (in European countries that weren’t so fond of catholics it was also rather negatively referred to as “papal poison”), there was no denying that the bark of the fever tree was a vast improvement on the alternative remedies of the time, which included such delights as amputation, bloodletting, and applying split pickled herrings to the feet. For a couple of centuries, the bark of the cinchona tree continued to be dried, ground into powder, and mixed into liquid for ingestion as a treatment, in much the same way as it had long been used by indigenous people of the Andes. But then, in 1820, the French scientists Pierre Joseph Pelleteir and Joseph Caventou succeeded in isolating one (of several) active ingredients from the fever tree bark: quinine.
Alongside quinine, which you may have heard of as an antimalarial pill (as it is still in use today!), fever tree bark also contains other chemicals that are quite effective as amntimalarials, namely quinidine, cinchonine, and cinchonidine. However, it was rather a matter of trade than a matter of science by which quinine came to be the most extensively used. Cleverly, the Dutch managed to dominate the global market in fever tree bark, in particular by transplanting cinchona trees to their colonies in today’s Indonesia. It just so happened that when cinchona trees were grown in Java, their bark contained a particularly high amount of quinine.
It can easily be argued that quinine changed the world. Access to quinine became a pivotal tool for colonial powers who wanted to expand into new frontiers where control of malaria (and other tropical diseases) was crucial to maintain power. Historians have even pinpointed quinine as “one of the major tools of imperialism that powered the British Empire.” Something similar could probably be said for the Dutch. Indeed, quinine was such a powerful agent against malaria that, thanks to the ready availability of quinine, malaria even became a sort of ‘treatment’ for syphilis.
These days, quinine is still used, alongside artemisinin, another striking example of modernized traditional medicine. In the 1940s, chloroquine treatment became the #1 antimalarial, but the malarial parasite, Plasmodium faciparum, developed antimicrobial resistance to chloroquine quite quickly, and by the 1980s quinine was brought back into regular use.
The most shocking and intriguing part of this whole story to me, is that we still don’t know exactly how quinine works. Quinine seems to somehow mess with the ability of Plasmodium to eat up our red blood cells, which is necessary to its own survival, but despite centuries of use, we still don’t know exactly how that happens. That was one awfully lucky, serendipitous guess by those 17th century Spanish Jesuits in the Andes.