History of malaria
The history of malaria extends from its prehistoric origin as a zoonotic disease in the primates of Africa through to the 21st century. A widespread and potentially lethal human infectious disease, at its peak malaria infested every continent except Antarctica. Its prevention and treatment have been targeted in science and medicine for hundreds of years. Since the discovery of the Plasmodium parasites which cause it, research attention has focused on their biology as well as that of the mosquitoes which transmit the parasites.
References to its unique, periodic fevers are found throughout recorded history, beginning in the first millennium BC in Greece and China.
For thousands of years, traditional herbal remedies have been used to treat malaria. The first effective treatment for malaria came from the bark of the cinchona tree, which contains quinine. After the link to mosquitos and their parasites was identified in the early 20th century, mosquito control measures such as widespread use of the insecticide DDT, swamp drainage, covering or oiling the surface of open water sources, indoor residual spraying, and use of insecticide treated nets was initiated. Prophylactic quinine was prescribed in malaria endemic areas, and new therapeutic drugs, including chloroquine and artemisinins, were used to resist the scourge. Today, artemisinin is present in every remedy applied in the treatment of malaria. After introducing artemisinin as a cure administered together with other remedies, malaria mortality in Africa decreased by half, though it later partially rebounded.
Malaria researchers have won multiple Nobel Prizes for their achievements, although the disease continues to afflict some 200 million patients each year, killing more than 600,000.
Malaria was the most important health hazard encountered by U.S. troops in the South Pacific during World War II, where about 500,000 men were infected.
At the close of the 20th century, malaria remained endemic in more than 100 countries throughout the tropical and subtropical zones, including large areas of Central and South America, Hispaniola, Africa, the Middle East, the Indian subcontinent, Southeast Asia, and Oceania. Resistance of Plasmodium to anti-malaria drugs, as well as resistance of mosquitos to insecticides and the discovery of zoonotic species of the parasite have complicated control measures.
One estimate, which has been published in a 2002 Nature article, claims that malaria may have killed 50-60 billion people throughout history, or about half of all humans that have ever lived. However, speaking on the BBC podcast More or Less, Emeritus Professor of Medical Statistics at Liverpool School of Tropical Medicine Brian Faragher voiced doubt about this estimate, noting that the Nature article in question did not reference the claim. Faragher gave a tentative estimate of about 4-5% of deaths being caused by malaria, lower than the claimed 50%. More or Less were unable to find any source for the original figure aside from works which made the claim without reference.
Origin and prehistoric period
The first evidence of malaria parasites was found in mosquitoes preserved in amber from the Palaeogene period that are approximately 30 million years old. Malaria protozoa are diversified into primate, rodent, bird, and reptile host lineages. The DNA of Plasmodium falciparum shows the same pattern of diversity as its human hosts, with greater diversity in Africa than in the rest of the world, showing that modern humans had had the disease before they left Africa. Humans may have originally caught P. falciparum from gorillas. P. vivax, another malarial Plasmodium species among the six that infect humans, also likely originated in African gorillas and chimpanzees. Another malarial species recently discovered to be transmissible to humans, P. knowlesi, originated in Asian macaque monkeys. While P. malariae is highly host specific to humans, there is some evidence that low level non-symptomatic infection persists among wild chimpanzees.About 10,000 years ago, malaria started having a major impact on human survival, coinciding with the start of agriculture in the Neolithic Revolution. Consequences included natural selection for sickle-cell disease, thalassaemias, glucose-6-phosphate dehydrogenase deficiency, Southeast Asian ovalocytosis, elliptocytosis and loss of the Gerbich antigen and the Duffy antigen on the erythrocytes, because such blood disorders confer a selective advantage against malaria infection. The three major types of inherited genetic resistance were present in the Mediterranean world by the time of the Roman Empire, about 2000 years ago.
Molecular methods have confirmed the high prevalence of P. falciparum malaria in ancient Egypt. The Ancient Greek historian Herodotus wrote that the builders of the Egyptian pyramids were given large amounts of garlic, probably to protect them against malaria. The Pharaoh Sneferu, the founder of the Fourth dynasty of Egypt, who reigned from around 2613–2589 BC, used bed-nets as protection against mosquitoes. Cleopatra VII, the last Pharaoh of Ancient Egypt, similarly slept under a mosquito net. However, whether the mosquito nets were used for the purpose of malaria prevention, or for more mundane purpose of avoiding the discomfort of mosquito bites, is unknown. The presence of malaria in Egypt from circa 800 BC onwards has been confirmed using DNA-based methods.
Classical period
Malaria became widely recognized in ancient Greece by the 4th century BC and is implicated in the decline of many city-state populations. The term μίασμα was coined by Hippocrates of Kos who used it to describe dangerous fumes from the ground that are transported by winds and can cause serious illnesses. Hippocrates, the "father of medicine", related the presence of intermittent fevers with climate and environmental conditions and classified the fever according to periodicity: Gk.:tritaios pyretos / L.:febris tertiana, and Gk.:tetartaios pyretos / L.:febris quartana.The Chinese Huangdi Neijing dating from ~300 BC – 200 AD apparently refers to repeated paroxysmal fevers associated with enlarged spleens and a tendency to epidemic occurrence.
Around 168 BC, the herbal remedy Qing-hao came into use in China to treat female hemorrhoids.
Qing-hao was first recommended for acute intermittent fever episodes by Ge Hong as an effective medication in the 4th-century Chinese manuscript Zhou hou bei ji fang, usually translated as "Emergency Prescriptions kept in one's Sleeve". His recommendation was to soak fresh plants of the artemisia herb in cold water, wring them out, and ingest the expressed bitter juice in their raw state.
"Roman fever" refers to a particularly deadly strain of malaria that affected the Roman Campagna and the city of Rome throughout various epochs in history. An epidemic of Roman fever during the 5th century AD may have contributed to the fall of the Roman Empire. The many remedies to reduce the spleen in Pedanius Dioscorides's De Materia Medica have been suggested to have been a response to chronic malaria in the Roman empire. Some so-called "vampire burials" in late antiquity may have been performed in response to malaria epidemics. For example, some children who died of malaria were buried in the necropolis at Lugnano in Teverina using rituals meant to prevent them from returning from the dead. Modern scholars hypothesize that communities feared that the dead would return and spread disease.
In 835, the celebration of Hallowmas was moved from May to November at the behest of Pope Gregory IV, on the "practical grounds that Rome in summer could not accommodate the great number of pilgrims who flocked to it", and perhaps because of public health considerations regarding Roman Fever, which claimed a number of lives of pilgrims during the sultry summers of the region.
Middle Ages
During the Middle Ages, treatments for malaria included blood-letting, inducing vomiting, limb amputations, and trepanning. Physicians and surgeons in the period used herbal medicines like belladonna to bring about pain relief in affected patients.European Renaissance
The name malaria is derived from mal aria. This idea came from the Ancient Romans, who thought that this disease came from pestilential fumes in the swamps. The word malaria has its roots in the miasma theory, as described by historian and chancellor of Florence Leonardo Bruni in his Historiarum Florentini populi libri XII, which was the first major example of Renaissance historical writing:The coastal plains of southern Italy fell from international prominence when malaria expanded in the 16th century. At roughly the same time, in the coastal marshes of England, mortality from "marsh fever" or "tertian ague" was comparable to that in sub-Saharan Africa today. William Shakespeare was born at the start of the especially cold period that climatologists call the "Little Ice Age", yet he was aware enough of the ravages of the disease to mention it in eight of his plays. Malaria was commonplace beside the River Thames then and into the mid-Victorian era.
Medical accounts and ancient autopsy reports state that tertian malarial fevers caused the death of four members of the prominent Medici family of Florence. These claims have been confirmed with more modern methodologies.
Spread to the Americas
Malaria was not referenced in the "medical books" of the Mayans or Aztecs. Despite this, antibodies against malaria have been detected in some South American mummies, indicating that some malaria strains in the Americas might have a pre-Columbian origin. European settlers and West African slaves could have brought other strains of malaria to the Americas in the 16th century.In his book 1493: Uncovering the New World Columbus Created, Charles Mann cites sources that speculate that the reason African slaves were brought to the British Americas was because of their resistance to malaria. The colonies needed low-paid agricultural labor, and large numbers of poor British were ready to emigrate. North of the Mason–Dixon line, where malaria-transmitting mosquitoes did not fare well, British indentured servants proved more profitable, as they would work toward their freedom. However, as malaria spread to places such as the tidewater of Virginia and South Carolina, the owners of large plantations came to rely on the enslavement of more malaria-resistant West Africans, while white small landholders risked ruin whenever they got sick. The disease also helped weaken the Native American population and made them more susceptible to other diseases. However, the theory that supposed resistance to Malaria is the reason for the use of Black labour on the plantation complexes, as opposed to economic or social reasons, has been questioned by historians of American and Caribbean slavery.
Malaria caused huge losses to British forces in the South during the Revolutionary War as well as to Union forces during the Civil War.