Malaria history is first mentioned in Chinese documents from around 2700 B.C. The word malaria comes from Italian and refers to the “bad air” that was believed to cause the disease. The connection between mosquitoes and malaria was not discovered until the 19th century.
Malaria history: how the disease has affected humanity
Malaria history staring with high frequently in areas where there were many mosquito breeding sites, such as swamps, marshes, rivers, and especially located in warm tropical regions where heat and a temperate climate abounded, yes, with some humidity involved. This disease was one of the greatest causes of suffering and death in human history. It is estimated that half, if not more, of the population of Rome suffered from malaria during the time of the Roman Empire.
It was in the 19th century that scientists such as Charles Laveran and Ronald Ross discovered that, in reality, parasites of the genus Plasmodium transmitted by Anopheles mosquitoes were the real cause of malaria transmission and contact. In 1897, Sir Ronald Ross, doing his corresponding research while staying in India, managed to demonstrate a finding that has been very helpful to this day: the complete life cycle of the malaria parasite, thus the mosquito fed with blood from an infected individual and went on to bite a healthy individual, thus transmitting the parasitic form of the disease.
A single mosquito bite on immemorial times in malaria history
Malaria history corresponds to one of the many diseases that crossed the species barrier, managing to become a zoonotic disease or infection, being transferred from animals to humans. Before it was believed that a person could be infected through the air, but it is not until they discover that this disease has a characteristic mechanical vector responsible for it. Being one of the smallest in the ecosystem, but one of the most virulent and lethal, a protozoan called Plasmodium falciparum, heading the list of the main parasites that generates this great health problem.
However, mosquitoes are simply carriers or vectors, since 2010
Malaria history illustrates the ravages of a disease that profoundly affected humanity, but also shows the triumphs of science and medicine in discovering its origins and developing effective treatments and controls. Although malaria remains a major health threat today, it represents a smaller fraction of the suffering it caused in the past.
Tracing the origin of the parasite has been quite a challenge…
It was not until 2010 that a group of scientists managed to find a breakthrough when evaluating fecal samples from western gorillas that contained the Plasmodium parasite. Investigating more in their studies, they realized that the version of the parasite in humans (P. falciparum) was quite similar to one of the parasitic agents that several of the gorillas in the study carried out. It was then, established for the first time in all the history, that the deadliest form of malaria in humans arose from chimpanzees and gorillas.
How did this happen? The answer is simple, in the same way that the mosquito infects the human. An Anopheles type mechanical vector bit an infected gorilla and, in turn, with another bite, the gorilla transmitted the parasite to a human being. Once the parasite was in people’s bloodstreams and liver cells, the disease could spread rapidly, obviously if enough mosquitoes gradually or equivalently existed to transmit the parasite from person to person.
However, the story was still incomplete. Since, especially, it was still not really clear when the parasite was transported from the gorilla to humans. The problem being that, the fecal samples only contained traces of the DNA that the gorilla possessed, and the scientific researchers needed enough blood samples to obtain the correct and complete order of the genome to determine the moment of transmission. However, we all can imagine or know in advance that getting blood from wild gorillas or chimpanzees is not an easy task.
Something that is curious in malaria, chimpanzees also have three different species of Plasmodium, and it was quite easy for them to get blood samples from chimpanzees. Some inhabitants of sanctuaries in Cameroon, a bit close to places where wild chimpanzees are located.
Some time later, a study that was published in the journal Nature Communications managed to obtain the full and complete sequence of the genomes of 2 parasites found in chimpanzees. Leading researchers to study the family tree of the genus Plasmodium more carefully and in greater detail. This, consequently, could corroborate the unimaginable clues about how deadly malaria could be and how it originated.
Information provided by the same researchers, reveal that it has been happening for more than ten thousand years ago, thus coinciding with the time in malaria history when humans began to form closed settlements and develop agriculture increasingly. All this change made it possible for them to move from one region to another, just as their ancestors did, giving mosquitoes a greater range and probability of infecting us through their bite, transcending malaria history.
Malaria history: a tale of a deadly disease in the 21st century
Many theories claim that if the parasite were a little older or had a higher incidence centuries earlier, it would surely have had a better opportunity to generate new mutations and show greater genetic diversity. That is why it is considered important to know about malaria history. On the other hand, Plasmodium species in gorillas and chimpanzees may have had as many millions of years to mutate, while P. falciparum showed few mutations when it first hosted humans, which was relatively recently.
Following that incredible logic, it is assumed that we should have seen several or very many transmissions of P. falciparum from gorillas to humans. Because, after all, there are mosquitoes and humans in areas where infected gorillas live.
And yet, that has not happened in any other way. None of the six known species of Plasmodium in apes are found in humans today, or at least for now. So the mystery of how P. falciparum was originally transmitted remains a mystery. The curious fact that it hasn’t happened more frequently reveals that our built-in barriers that normally prevent cross-species transmission are working correctly most of the time.
Nowadays, there is a worldwide sanitary and epidemiological control. There are various methods to prevent the bite of infected mosquitoes, and drugs to combat malaria effectively; Chloroquine phosphate, although many parasites have developed resistance to the drug. But, without a doubt, with technological advances it has been possible to restore integrity and well-being by reducing these cases for malaria history.