Chapter 17-Molecules Versus Malaria

What is Malaria?

Malaria, in it’s full form of the word, means “bad air”. It is caused by a microscopic parasite and said to be the greatest killer of humanity for all time. Malaria is transmitted far more rapidly than AIDS. Statistics provide the fact that HIV-positive patients infect between two and ten others, while infected malaria patients can transmit the disease to hundreds of people. There are four different species of the malaria parasite that impact human lives: Plasmodium vivax, Plasmodium falciparum, Plasmodium malariae, and Plasmodium ovale. All four cause the same typical symptoms–intense fever, chills, terrible headache, and muscle pains. The most lethal, however, is the falciparum malaria; the others are sometimes referred to as benign. Malaria is transmitted from one human to another trhough the bite of the anopheles mosquito. Malaria is now considered as a tropical or semitropical disease, but before it was widespread in temperate regions also.

Key Facts About the History of Malaria

The earliest records of malaria occurred in China, India, and Egypt thousands of years ago. The English called the disease “the ague”. It was common in the low-lying coastal regions of England and the Netherlands with extensive marshlands and slow-moving waters. The disease also occurred in even more northern communities such as Scandinavia, the northern United States, and Canada. It was an endemic in many countries bordering the Mediterranean Sea and the Black Sea. Rome was notorious for its deadly “swamp fever” and each time a papal conclave was held, many attending cardinals died from malaria. In Crete and the Peloponnesus peninsula of Greece, people would move their animals to the high hills of the country to escape the disease in summer months. Alexander the Great supposedly died of malaria, as well as David Livingstone, the African explorer. Over half of the troops in the American Civil War suffered from malaria. Even some of Napoleon’s troops suffered the disease in 1812 on their way to Moscow. In the United States, there were more than half a million cases of malaria at the beginning of World War I. It remained a worldwide problem well into the twentieth century.

The Chemistry of Malaria

High in the Andes Mountains, there are trees with bark that contain an alkaloid molecule, known as quinine. There are about forty species of this tree, but all members are part of the Cinchona genus. The trees are indigenous to the eastern slopes of the Andes, from Colombia to Bolivia. The people who live there knew that the tea brewed from this part of the tree was an effective fever cure. There are many stories that include this tree and its wonderful effects. There are records where the tree bark actually saved the people’s lives. Though the bark was good for more things than just curing malaria; it also worked for indigestion, fever, hair loss, cancer, and many other conditions. No one really knew where the bark came from until a botanist, Joseph de Jussieu, discovered that the source was various species of a broad-leafed tree. It was a member of the Rubiaceae, which was the same family as the coffee tree. With its rapid rate of growth, by the end of the eighteenth century, and estimated 25,000 quina trees were being cut down each year. Because of this, the tree was becoming endangered, and the need to isolate, identify, and manufacture the molecule became more and more important. Although many experiments had been tried, none were successful until 1820 that Joseph Pelletier and Joseph Caventou managed to extract and purify quinine. William Perkin tried to combine two molecules of allyltoluidine with three atoms of oxygen to form quinine and water. In doing this, he realized that the quinine molecule was more complex than he thought. The quinine structure has a hydrogen atom pointing out of the page and a hydroxide molecule directed behind the page around the carbon atom adjacent to the ring system. Extensive research on antimalarial drugs during World War II resulted in a 4-aminoquinoline derivative, known as choloroquine, as a synthetic choice of quinine. For over forty years, chloroquine was safe and effective against malaria. Unfortunately, the malaria parasties began to adapt quickly to the molecule and the effectiveness of chloroquine declined.  None of these ways kept the cost or the rapid pace of the spread of malaria down. The best the chemists could do against the attack of the mosquitoes was to create an insecticide. Initially, the most important one was DDT because it interfered with the nervous system of the mosquitoes and caused them to die. It was inexpensive and it seemed to have little toxicity for other forms of animal life. But, however, the effect of DDT became obvious as devastating bioaccumulation became evident.

Impact on the Modern World

In the modern world, I believe the use of these molecules have faded. Because of the rapid use of the molecules of quinine, chloroquine, and DDT, a lot of the world has become virtually malaria-free. Since 2000, 45% of the malaria cases have declined worldwide. The only downside to finding a cure to the malaria disease was the molecule of DDT caused a bioaccumulation that was outlawed in 2001 under the Stockholm Convention. I understand the molecules of quinine were too expensive, but maybe if people tried again, they could find a new cure. Since the world we know today has more technology, maybe the cure would be easier to find. Couteur and Burreson agree that the world would be completely different had the molecules of quinine, cholorquine, and DDT had been or had not been found. They explained how the effects of the early years would affect the later ones. I know, however, there are still associations trying to find new cures for the disease, and so, not only have the molecules faded, but new ones are becoming more prominent as time wears on.

Advertisements
Categories: Uncategorized | 1 Comment

Post navigation

One thought on “Chapter 17-Molecules Versus Malaria

  1. This post is well organized and contains all the right information. This post seems to contain all the necessary information that helps me to better understand this chapter, and by better understanding this chapter i therefore better understand myself. Thank you for this.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

Blog at WordPress.com.

%d bloggers like this: