Malaria or a disease resembling malaria has been noted
for more than 4,000 years. From the Italian for "bad air," mal'aria
has probably influenced to a great extent human populations and human history.
Ancient
History (2700 BCE-340 CE)
The symptoms of malaria were described in ancient
Chinese medical writings. In 2700 BC, several characteristic symptoms of what
would later be named malaria were described in the Nei Ching, The Canon of
Medicine). Nei Ching was edited by Emperor Huang Ti. Malaria became widely
recognized in Greece by the 4th century BCE, and it was responsible for the
decline of many of the city-state populations. Hippocrates noted the principal
symptoms. By the age of Pericles, there were extensive references to malaria in
the literature and depopulation of rural areas was recorded. In the Susruta, a
Sanskrit medical treatise, the symptoms of malarial fever were described and
attributed to the bites of certain insects. A number of Roman writers
attributed malarial diseases to the swamps.
In China, during the second century BCE, the Qinghao
plant (Artemisia annua) was described in the medical treatise, 52 Remedies,
found in the Mawangdui Tomb. In the United States, this plant is known as the
annual or sweet wormwood. In 340 CE, the antifever properties of Qinghao were
first described by Ge Hong of the East Yin Dynasty. The active ingredient of
Qinghao, known as artemisinin, was isolated by Chinese scientists in 1971.
Derivatives of this extract, known collectively as artemisinins, are today very
potent and effective antimalarial drugs, especially in combination with other
medicines.
Quinine
(Early 17th Century)
Following their arrival in the New World, Spanish Jesuit
missionaries learned from indigenous Indian tribes of a medicinal bark used for
the treatment of fevers. With this bark, the Countess of Chinchón, the wife of
the Viceroy of Peru, was cured of her fever. The bark from the tree was then
called Peruvian bark and the tree was named Cinchona after the countess. The
medicine from the bark is now known as the antimalarial, quinine. Along with
artemisinins, quinine is one of the most effective antimalarial drugs available
today.
Discovery
of the Malaria Parasite (1880)
Charles Louis Alphonse Laveran, a French army surgeon
stationed in Constantine, Algeria, was the first to notice parasites in the
blood of a patient suffering from malaria. This occurred on the 6th of November
1880. For his discovery, Laveran was awarded the Nobel Prize in 1907.
Differentiation of Species of
Malaria (1886)
Camillo Golgi, an Italian
neurophysiologist, established that there were at least two forms of the
disease, one with tertian periodicity (fever every other day) and one with
quartan periodicity (fever every third day). He also observed that the forms
produced differing numbers of merozoites (new parasites) upon maturity and that
fever coincided with the rupture and release of merozoites into the blood
stream. He was awarded a Nobel Prize in Medicine for his discoveries in
neurophysiology in 1906.
Naming of Human Malaria Parasites (1890, 1897)
The Italian
investigators Giovanni Batista Grassi and Raimondo Filetti first introduced the
names Plasmodium
vivax and P. malariae for two of the malaria parasites that
affect humans in 1890. Laveran had believed that there was only one species, Oscillaria malariae.
An American, William H. Welch, reviewed the subject and, in 1897, he named the
malignant tertian malaria parasite P. falciparum. There were many arguments against the use of
this name; however, the use was so extensive in the literature that a change
back to the name given by Laveran was no longer thought possible. In 1922, John
William Watson Stephens described the fourth human malaria parasite, P. ovale. P. knowlesi was first described by Robert Knowles
and Biraj Mohan Das Gupta in 1931 in a long-tailed macaque. The first
documented human infection with P. knowlesi was
in 1965.
Discovery That Mosquitoes Transmit Malaria Parasites
(1897-1898)
On
August 20th, 1897, Ronald Ross, a British officer in the Indian Medical
Service, was the first to demonstrate that malaria parasites could be
transmitted from infected patients to mosquitoes. In further work with bird
malaria, Ross showed that mosquitoes could transmit malaria parasites from bird
to bird. This necessitated a sporogonic cycle (the time interval during which
the parasite developed in the mosquito). Thus, the problem of malaria
transmission was solved. For his discovery, Ross was awarded the Nobel Prize in
1902.
Discovery of the Transmission of the Human Malaria
Parasites Plasmodium (1898-1899)
Led by
Giovanni Batista Grassi, a team of Italian investigators, which included Amico
Bignami and Giuseppe Bastianelli, collected Anopheles claviger mosquitoes
and fed them on malarial patients. The complete sporogonic cycle of Plasmodium falciparum, P. vivax, and P. malariae was demonstrated. In 1899, mosquitoes
infected by feeding on a patient in Rome were sent to London where they fed on
two volunteers, both of whom developed malaria.
The Panama Canal (1905-1910)
The
construction of the Panama Canal was made possible only after yellow fever and
malaria were controlled in the area. These two diseases were a major cause of
death and disease among workers in the area. In 1906, there were over 26,000
employees working on the Canal. Of these, over 21,000 were hospitalized for
malaria at some time during their work. By 1912, there were over 50,000
employees, and the number of hospitalized workers had decreased to
approximately 5,600. Through the leadership and efforts of William Crawford
Gorgas, Joseph Augustin LePrince, and Samuel Taylor Darling, yellow fever was
eliminated and malaria incidence markedly reduced through an integrated program
of insect and malaria control.
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