Cinchona, the malaria remedy
It was said that the wife of Luis Jerónimo de Cabrera, 4th Count of Chinchón（1589–1647）also the governor of Peru, had malaria, and Dr. Juan de Vega who tried all the methods to treat it suggested trying “Ecuadorian Bark.” It sounds incredible, but because there is nothing else to do, Count Chinchón agreed to give it a try… and it worked. When Carl Linnaeus named the cinchona tree in 1753, he named it after Count Chinchón in memory of this event. However, he misspelled Count Chinchón’s last name; and it became a “cinchona” tree.
Cinchona is native to the Andean highlands of South America. There are about forty species of cinchona trees in the local area. The curative effects of different species on malaria vary greatly. The Jesuit priests learned to use cinchona bark from the Indians of Peru and introduced it to Europe, so the cinchona bark is also called “Jesuit’s bark”. At the time when different sects were mutually exclusive, it was said that because of this name, Oliver Cromwell (1599–1658) refused to take it, and eventually died of malaria.
From Huangdi Neijing （黃帝內經，the Inner Canon of the Yellow Emperor or Esoteric Scripture of the Yellow Emperor）, there are records of malaria. Malaria is an ancient disease that has claimed the lives of many people, including Alexander the Great (356BC-323BC) who established an empire spanning Europe, Asia, and Africa. The Holy See even had to move to Avignon, France for 68 years because of the Roman malaria pandemic in the early 14th century! When Europeans discovered the New World, malaria also immigrated with them; later, malaria appeared all over the world except Antarctica.
Before cinchona, Europeans cannot do anything with malaria. This can be seen from the malaria treatment recorded in ancient books at the time: in addition to bloodletting and herbal medicine, there was even reading “Iriad”! So the discovery of the cinchona tree is really like finding a life-saving elixir for Europeans! However, it takes 4.4 kilograms of bark to cure each disease; and the early peeling uses the girdling method, which makes the tree die after the bark is peeled. By 1795, 25,000 cinchona trees had to be cut down every year; but it would take ten years for newly planted trees to start peeling, and it would not be able to keep up! Because the cinchona tree is so important to European countries, the British Kew Garden sent two plant hunters, Richard Spruce and Clements R. Markham, to South America to find the cinchona tree in 1858, and then began to plant it in Java and India.
In addition to planting trees, scientists are also trying to find key ingredients from cinchona that can cure malaria. Finally in 1820, French scientists Joseph Bienaimé Caventou and Pierre Joseph Pelletier isolated quinine from cinchona bark. During World War II, because Japan occupied Java, the source of quinine was interrupted, which accelerated the pace of the American invention of chloroquine.
After World War II, the World Health Organization launched a campaign to eradicate malaria. In addition to treating malaria patients with chloroquine, DDT was sprayed everywhere, diesel oil was sprayed in the ditch, and mosquito nets were hung. It was very successful at first, but later it was discovered that DDT was toxic, Plasmodium has developed resistance to chloroquine, and Anopheles have also become resistant to DDT.
More and more malaria parasites are becoming resistant to chloroquine, leading China to start r looking for a malaria remedy in 1967. In the beginning, it was not very smooth. Later, Ms. Tu Youyou realized that lower temperatures should be used according to the book “First Aid in TCM （肘後備急方）” by Ge Hong of the Eastern Jin Dynasty. Low temperature extraction finally extracted artemisinin from Artemisia annua in 1971. This discovery also earned her the 2015 Nobel Prize in Physiology and Medicine.
Although the discovery of artemisinin has brought hope for the eradication of malaria; but malaria, an ancient disease, will not be so easy to give up! By 2015, artemisinin-resistant malaria parasites had appeared in Khmer, Laos, Vietnam, Myanmar and Thailand.
Now the eradication of malaria is mainly for everyone’s health, but in the 17th to the early 20th century, the reason why European countries paid so much attention to cinchona was mainly to stabilize the supply of labor. At that time, many employers would buy quinine for workers to ensure productivity; the British government even provided free quinine to those willing to immigrate to India, making it possible for many British people to immigrate for quinine until India’s first war of independence. In fact, without quinine, it would be impossible for the British to establish a colony in Nigeria in the nineteenth century: 350–800 per thousand caucasians who came to Africa at that time died of malaria, so Africa was called “white man’s grave” . It can be seen that this seemingly inconspicuous tree has affected the destiny of many countries; if those Indians knew the impact of Cinchona on European colonization in the world, would they still teach the Jesuit priests to use it?
Cinchona was introduced to Taiwan in the early 20th century by Japanese. It was planted in many areas in hope to produce quinine. However, these trees are ignored after Japan took over Indonesia during World War II. We can still find some cinchona trees in Liugui area and Shitou.
Malaria is so terrible, but it was once used as a cure! At the beginning of the twentieth century, Austrian physician Julius Wagner-Jauregg (1857–1940) discovered that Treponema pallidum (the pathogen of syphilis) is sensitive to heat, so he developed a method of curing syphilis. By inoculating the malaria parasite on patients with terminal syphilis, and causing the patients to have a high fever when malaria attacks, that will kill the T. pallidum. After three or four rounds of fever, T. pallidum is eradicated, then quinine was used to treat malaria. It sounds unbelievable, but in the era before antibiotics, this method was not only adopted, he was also awarded the 1927 Nobel Prize in Physiology and Medicine. This method was later replaced by antibiotics in the 1950s.
