The World-Altering Mosquito – Part 1

How the mosquito shaped the United States.

Baseball season has started, and it’s also that time of year in Virginia and other warm climes when mosquitos come out to ruin otherwise pleasant summer evenings.  (Studies show that blood type O seems to be the blood type mosquitoes tend to prefer, with people with blood type O getting bitten twice as often as those with type A, and with type B falling somewhere in between.)  But in the next couple of essays, we’ll examine the astonishing historical carnage caused throughout human history by that tiny summer pest.

In his book The Mosquito: A Human History of Our Deadliest Predator, Timothy Winegard introduces us to the grand scope of the mosquito-borne illness casualties humanity has suffered through history:

The mosquito has killed more people than any other cause of death in human history. Statistical extrapolation situates mosquito-inflicted deaths approaching half of all humans that have ever lived. In plain numbers, the mosquito has dispatched an estimated 52 billion people from a total of 108 billion throughout our relatively brief 200,000- year existence. Yet, the mosquito does not directly harm anyone. It is the toxic and highly evolved diseases she transmits that cause an endless barrage of desolation and death. Without her, however, these sinister pathogens could not be transferred or vectored to humans nor continue their cyclical contagion. In fact, without her, these diseases would not exist at all. You cannot have one without the other.

To get a graphic sense of exactly how the mosquito delivers these diseases to humans (in somewhat disturbing detail), check out this three-minute video from PBS’s Deep Look series:

As Winegard continues:

[Mosquitos have] played a greater role in shaping our story than any other animal with which we share our global village … Mosquitoes and her diseases that have accompanied traders, travelers, soldiers, and settlers around the world have been far more lethal than any man-made weapons or inventions. The mosquito has ambushed humankind with unmitigated fury since time immemorial and scratched her indelible mark on the modern world order.

In this essay, we’ll focus on one of main viruses spread by mosquitos that has particularly shaped the geography of the United States: yellow fever.  As Winegard writes:

Occupying the top tier of the virus class is yellow fever, which often amplified and accompanied endemic malaria. It is an accomplished killer, first stalking humans in Africa about 3,000 years ago. Until recently, it was a global historical game- changer. This adversary targets healthy, young adults in the prime of life. Although a successful vaccine was discovered in 1937, between 30,000 and 50,000 people still die annually of yellow fever, with 95% of fatalities occurring in Africa … [T]he gnawing terror that yellow fever implanted in pacing and brooding populations across the world, especially in the European colonial outposts of the New World. The first definitive outbreak in the Americas occurred in 1647, disembarking with African slaves and fugitive mosquitoes. It must have been agonizing to wonder when and where “Yellow Jack,” as the British christened it, would strike next. While fatality rates from yellow fever averaged around 25%, depending on the strain and conditions of an epidemic, it was not uncommon for death rates to reach 50%. A handful of outbreaks reached 85% in the Caribbean. The salty sea stories of ghost ships like the Flying Dutchman are based on true accounts; whole crews might succumb to yellow fever, months passing before the aimlessly drifting ships were corralled. Boarding parties were greeted with nothing but the stench of death and the rattle of skeletons with no revealing clues as to the cause. Luckily for survivors, who are left incapacitated for weeks, yellow fever is a one-shot deal. Lifetime immunity is imparted to those who defang the dogged virus.

Yellow fever hit the British colonies in America hard:

The deadly virus first surfaced in British North America courtesy of the Royal Navy in transit from the Caribbean to attack Quebec. Mooring with the flotilla at the port of Boston in 1693, yellow fever sparingly killed only 10% of the 7,000 townsfolk … Prior to the American Revolution, there were at least thirty major yellow fever epidemics in the British North American colonies, striking every major urban center and port on the 1,000-mile stretch of seaboard from Nova Scotia to Georgia … [Y]ellow fever became the topic of fear, loathing, and legend, most notably at port cities that operated as the choke points for slaving and trading vessels of all nations. These ships of death ferried mosquito-borne disease across the Western Hemisphere and beyond. New Orleans, Charleston, Philadelphia, Boston, New York, and Memphis head a lengthy list of American cities that would experience deadly yellow fever epidemics. In fact, these were the most lethal epidemics of any disease in American history.

The spread of malaria during the Revolutionary War is one of the most under-appreciated causes of America’s victory.  To be sure, mosquito-borne diseases ravaged Americans as well, so much so that quinine became an essential war material.  As described by Ada McVean:

Quinine is isolated from the bark of the cinchona tree, which has been used for hundreds of years by groups like the Quechua people to treat maladies like shivers and diarrhea. In the 1700s a Scottish doctor, George Cleghorn, discovered that quinine could be used to treat malaria. This quickly led to tonic water being drunk by British soldiers stationed in India to fight malaria. But as you may know, tonic water is quite bitter. So, in the 1800s, soldiers took to adding first gin, and eventually lemon and lime to their tonic water, to hide the bitter flavour, thus inventing the classic … gin and tonic.

Quinine helped save colonial soldiers, and their commander-in-chief.  As Winegard writes:

A month after the opening salvos of the American Revolution at Lexington and Concord in April 1775, the newly appointed commander in chief of the Continental Army, George Washington, had a request for his political masters in the Continental Congress. He urged them to buy up as much cinchona bark and quinine powder as possible. Given the dire financial pressures of the squabbling colonial government, and the dearth of pretty much everything needed to fight a war, his total allotment was a paltry 300 pounds. General Washington was a frequent visitor to the quinine chest as he suffered from recurrent bouts (and reinfection) of malaria since first contracting the disease in 1749 at the age of seventeen. Luckily for the Americans, the British were also drastically short of Peruvian Spanish-supplied quinine throughout the war. In 1778, shortly before they entered the fray in support of the American cause, the Spanish cut off this supply completely. Any available stores were sent to British troops in India and the Caribbean. At the same time, the mosquito’s merciless, unrelenting strikes on unseasoned [that is, “not acclimated”] British troops lacking quinine during the final British southern campaign -- launched in 1780 with the capture of Charleston, the strategic port city and mosquito sanctuary -- determined the fate of the United States of America … As J. R. McNeill colorfully contours, “The argument here is straightforward: In the American Revolution the British southern campaigns ultimately led to defeat at Yorktown in October 1781 in part because their forces were much more susceptible to malaria than were the American … [T]he balance tipped because Britain’s grand strategy committed a larger proportion of the army to malarial (and yellow fever) zones.” A full 70% of the British Army that marched into this southern mosquito maelstrom in 1780 was recruited from the poorer, famished regions of Scotland and the northern counties of England, outside the malaria belt of Pip’s Fenland marshes. Those who had already served some time in the colonies had done so in the northern zone of infection and had not yet been seasoned to American malaria. General Washington and the Continental Congress, on the other hand, had the advantage of commanding acclimated, malaria- seasoned colonial troops. American militiamen had been hardened to their surroundings during the Seven Years’ War and the turbulent decades heading toward open hostilities against their king. Washington personally recognized, albeit short of scientific affirmation or medical endorsement, that with his recurrent malarial seasonings, “I have been protected beyond all human probability or expectation.” While they did not know it at the time, this might well have been the Americans’ only advantage over the British when, after twelve years of seething resentment and discontent since the passing of the Royal Proclamation, war suddenly and unexpectedly came … In his detailed investigation Slavery, Disease, and Suffering in the Southern Lowcountry, Peter McCandless dissects the role of mosquitoes in attaining American independence, in a meticulous chapter titled “Revolutionary Fever.” He argues that “reading the evidence in contemporary accounts, it is hard to escape the conclusion that the biggest winners in the Southern campaigns were the microbes and the mosquitoes that transported so many of them … In terms of the outcome of the war, mosquito bites may have done more than partisan bullets to ensure an American victory.” The mosquito consumed British forces and ultimately decided the fate of the revolution and, by extension, the world as we now know it … [A]s the Americans were seasoned and somewhat shielded, they did not contract, or die from, mosquito-borne diseases at the same rate as their unseasoned British counterparts. As a result, the Americans retained their punching power and combat effectiveness.

After the American Revolution, yellow fever struck the nation’s capital, Philadelphia:

In then-US capital Philadelphia in 1793, as we will see, yellow fever killed over 5,000 people in three months. An additional 20,000 fled the city in terror, including President George Washington. The government ceased to function. Whispers of moving the nation’s capital to a safer location quietly entered political dialogue and casual conversation … Prior to the historic epidemic of 1793, Philadelphia had not seen yellow fever for thirty years. The population, therefore, was relatively unseasoned and ripe for infection. In July 1793, the Hankey, dubbed the “Ship of Death,” docked at the nation’s capital, carrying roughly 1,000 French colonial refugees fleeing Haiti. A few days later, in a brothel next to the pier in a seedy area known as Hell Town, a prowling scourge of yellow fever was let loose on Philadelphia’s unsuspecting population of 55,000. In total, 20,000 people fled the city, including most politicians and civil servants who were not already dead. Yellow fever shut down the federal government of the United States (and the Pennsylvania state government, both of which resided in Philadelphia). President Washington endeavored to govern from his perch in Mount Vernon but, in his hurried flight, remarked, “I brought no public papers of any sort (not even the rules which have been established in these cases), along with me. Consequently, am not prepared at this place to decide points which may require a reference to papers not within my reach.” He was advised that he did not have the power to relocate the capital and convene Congress at an alternate location because that “would clearly be unconstitutional.” By late October, as mosquitoes succumbed to the onset of winter chills, the city was described by First Lady Martha Washington as having “suffered so much that it can not be got over soon by those that was in the city— almost every family has lost some of their friends— and black seems to be the general dress of the city.” The 1793 yellow fever epidemic killed 5,000 people in roughly three months, nearing 10% of the capital city’s population … In December 1799, as 1,200 more yellow fever victims were being mourned in Philadelphia, sixty-seven-year-old George Washington died. That autumn he had suffered another bout of his reoccurring malaria, leading to a string of other complications.

But at around the same time, the mosquito was laying the seeds of the American’s acquisition of vast new territory.  As Winegard writes:

French colonial refugees fleeing a vicious slave revolt against French rule in Haiti swamped Philadelphia in yellow fever. [But] in the wake of the American Revolution, the mosquito connected four seemingly unrelated events over the span of fourteen years: the outbreak of the French Revolution in 1789, the rebellion launched in Haiti in 1791 led by Toussaint Louverture, followed by the appalling 1793 yellow fever epidemic in Philadelphia, and, finally, the completion of the Louisiana Purchase of 1803.

Here's how Winegard details that chain of events:

France had acquired Haiti, the western portion of the island of Hispaniola, in 1697 during the colonial wars preceding the Seven Years’ War. At the onset of the slave revolt in 1791, Haiti (called Saint-Domingue until the expulsion of the French) had 8,000 plantations and produced half of the world’s coffee. It was also a leading exporter of sugar, cotton, tobacco, cocoa, and indigo, which was used as a posh purple-blue fabric dye. The petite island colony accounted for an astounding 35% of France’s total mercantilist economic empire. Predictably, it was also the leading destination for African slaves (and imported mosquitoes), with 30,000 arriving annually. By 1790, Haiti’s half a million slaves, two-thirds of which were born and seasoned in Africa, made up 90% of the total population. Most African-born Haitian slaves arrived preseasoned to malaria and yellow fever … Fearing a domino effect of slave revolts, the British intervened in 1793 … [But in] 1798, the mosquito chased the once mighty and now aching British Army from Haiti … Without Haiti (and its vast resources), New Orleans served no purpose and was defenseless against attacks by the powerful British Royal Navy or even by the weaker but aggrieved United States. Napoleon also feared that without economic concessions in Louisiana the United States would, in Jefferson’s words, “marry ourselves to the British fleet and nation.” Haitian mosquitoes had emptied the economic veins of France. With finances and resources increasingly needed for his war in Europe, Napoleon understood the futility of pursuing his crippled North American strategy. The stinging success of Haiti’s mosquito-succored slaves had unintended historical implications that would eventually broker the Louisiana Purchase and quickly scatter and steer Lewis and Clark, and Sacagawea, across the United States … Following the loss of Haiti, Napoleon had no use for New Orleans or his vast, relatively barren Louisiana estate. Seeing as France was at war with both Spain and Britain, the sale of not just New Orleans but the entire 828,000 square miles of Louisiana Territory to the United States was the only option. Jefferson had given his negotiators permission to spend up to $10 million on New Orleans alone, and they were dumbfounded by, and immediately accepted, Napoleon’s offer of $15 million ($300 million today) for the entire French property holdings. The vast territory stretching from the Gulf of Mexico in the south to southern Canada in the north, from the Mississippi River in the east to the Rocky Mountains in the west, included land from fifteen current US states and two Canadian provinces. The 1803 Louisiana Purchase, brokered with the pressure of Haiti’s mosquitoes, doubled the size of the United States overnight at less than three cents an acre. Given her immeasurable impact in shaping the United States, including the addition of the Louisiana Territory, the mosquito deserves a place on Mount Rushmore with her protuberant face tucked in between the grateful glances of the indebted Washington and Jefferson.

In the next essay in this series, we’ll explore how the mosquito helped create the market for slavery worldwide, and also helped end it in America.

Links to all essays in this series: Part 1; Part 2.