The Mosquito summary

Human beings have evolved a variety of genetic defenses against malaria – many of them with strange-sounding names, like Duffy negativity, thalassemia and favism. But these defenses have been mixed blessings, which have often felt more like curses to their recipients. One of the most well-known examples provides a case in point: sickle cell trait – also known as sickle cell anemia. 

The story of this trait begins 8,000 years ago, when the agricultural Bantu-speaking people of West Central Africa started settling along the Niger River delta. The area was great for cultivating yams and plantains. Unfortunately, it was also home to swarms of malaria-infected mosquitos. The disease decimated the population, who were defenseless against it. 

Leaving southern Africa, let’s now turn to the dawn of Western civilization. We’ll begin in the fifth century BCE, when there were two rival superpowers vying for supremacy over the Mediterranean world: the Persian Empire and Greece.

At the time, Greece was divided into rival city-states, which were dominated by two coalitions – one led by Sparta, the other by Athens. During the Greco-Persian Wars of 499 to 449 BCE, these coalitions united against the invading Persian Empire, but even with their combined military forces, they were heavily outnumbered by their powerful Persian adversaries. 

By the time the Spartans won the Peloponnesian War in 404 BCE, most of southern Greece lay in ruins. The devastation left by the war was further amplified by endemic malaria, which drained Greece of its population and led to farms, mines and ports being left unattended. 

With southern Greece in tatters, a relatively unscathed and isolated kingdom was able to emerge and fill the power vacuum. Its name was Macedon, and it was eventually led by a man who became known as Alexander the Great. 

When we think of ancient Rome, our minds often conjure up images of grandeur, like the Colosseum, the Pantheon and other architectural marvels. 

But here’s a fact that our more glamorizing portrayals of Rome often leave out of the picture: from ancient times to the mid-twentieth century, the Eternal City was surrounded by 310 square miles of marshland, known as the Pontine Marshes. And by now, you know what that means: lots of mosquitos – and lots of malaria. 

You’ve no doubt heard the saying that “all roads lead to Rome.” The underlying idea is that the Roman Empire linked much of Europe together. It did that literally, by roads, but also economically, politically and culturally, by trade and conquest. That set the stage for the widespread transmission of both diseases, like malaria, along with ideas, like those of Christianity.

The spread of the disease helped to accelerate the spread of the religion. Unlike Roman paganism, Christianity presented itself as a healing religion. The early Christians believed they had a religious duty to tend to the sick, and they practiced what they preached by conducting healing rituals, providing nursing care and setting up hospitals. This made the religion very appealing to many Europeans during the third century CE, when the continent was wracked by malaria and other epidemics. 

You probably know 1492 as the year that Christopher Columbus sailed west in search of a shortcut to Asia, only to accidentally run into an island off the coast of North America. But it wasn’t just Columbus and his crew who inadvertently reached the shores of the Western hemisphere on that fateful mistake of a journey, it was also mosquito-borne diseases – most notably our ancient enemy, malaria. 

Prior to 1492, the Western hemisphere was home to plenty of mosquitos, but they didn’t carry any diseases. When Europeans and enslaved Africans landed in the Americas, they unwittingly brought disease-ridden mosquitos with them. 

As Spain, Portugal, France and Great Britain established and expanded their colonies in the Americas during the sixteenth, seventeenth and eighteenth centuries, the European colonists faced a major problem. 

In areas such as the Caribbean and the American South, they wanted to grow massive amounts of cash crops like sugar, cocoa, coffee, tobacco and cotton. But to do that, they needed an equally massive amount of labor power. At first, many of them turned to enslaved indigenous people and European indentured servants. But those enslaved people and servants kept dying from malaria and other mosquito-borne diseases, which thrived in the same conditions as the crops. 

When the American Civil War began in 1861, the rebelling southern Confederacy was significantly weaker than its northern Union opponent on nearly every front: weapons technology, military size, industrial development, infrastructure, natural resources – you name it. 

In light of this lopsided situation, President Abraham Lincoln hoped for a speedy resolution to the conflict. His initial objective was therefore limited. He simply wanted to convince the Confederacy to surrender as quickly as possible, so as to preserve the United States. And for him, that meant simply bringing the South back into the fold and returning to the way things were before the war began. He had no intention of obliterating the South’s military, subjugating it to Northern rule or ending slavery. 

Soon after the American Civil War ended in 1865, the US began planting the seeds from which it eventually grew into a global power. Of course, it didn’t cultivate those seeds all by itself; it got some considerable assistance from our ancient adversary, the mosquito. 

Here’s the back story. As early as the 1820s, the US had been eyeing Cuba, which was under Spanish rule at the time. Five presidents offered to buy the island from Spain; five presidents had their offers rejected. In the 1870s, American corporations started pouring capital into Cuba, and by 1877, the US was purchasing 83 percent of its exports. Around the same time, current and former enslaved people of African descent began to rebel against Spanish rule in Cuba. 

Here’s a lingering question from the previous blink: After coveting Cuba for so long, why didn’t the US just annex it at the end of the Spanish-American War? 

Well, that would have required a US military occupation. And that, in turn, would have entailed subjecting US troops to the same mosquito-ruined fate as their Spanish foes. Indeed, by the end of the four-month war, 4,700 US servicemen had already died from mosquito-borne diseases – yellow fever chief among them. The US didn’t want to risk any more deaths, so it withdrew its troops. 

After Dr. Gorgas’s great success in Cuba, the US government redeployed him to Panama, where he used the same tactics he’d developed in the Caribbean to fend off mosquitos during the building of the Panama Canal. 

When the canal was finished in 1914, the significance of the achievement wasn’t a matter of engineering alone; it also represented a historic victory against humankind’s worst enemy. Spain, Scotland, England and France had all previously tried to colonize Panama – and all of them had been bloodily rebuffed by mosquito-borne diseases. Thanks to Dr. Gorgas’s mosquito-fighting measures, the US was now able to eliminate yellow fever entirely and reduce malarial infections of the canal’s workers by 90 percent. 

In 1874, a pair of German and Austrian chemists synthesized DDT for the first time – but they were unaware of its greatest superpower: killing insects. 

The discovery of DDT’s insecticidal potential wouldn’t be made until 1939, when it was hit upon by a German-Swiss scientist Paul Hermann Müller. Thanks to his Nobel Prize-winning research, Western governments, militaries and farmers alike learned that DDT was lethal to a wide range of pestilent insects, such as Colorado potato beetles, fleas, lice, ticks, sandflies and, of course, mosquitos. 

Since the resurgence of mosquito-borne diseases in the 1970s, the vast majority of malaria cases have occurred and continue to occur in deeply impoverished parts of the world, such as sub-Saharan Africa. The latter currently bears the brunt of 85 percent of all cases of the disease, while 55 percent of the region’s population lives on less than $1 a day. 

Lacking a profit motive, pharmaceutical companies have spent very little money on researching and developing new antimalarial drugs to replace the ones that have become ineffective. In the twenty-first century, non-profit organizations such as the Gates Foundation have stepped in to fund antimalarial research, but an effective cure has yet to be found.