The Spread of Contagious Disease from the Old World to the New

"The European conquest of the Americas had relatively little to do with military prowess or superior technology; it was largely the result of the ravages of disease."

-Gerald N. Grob

The Age of Exploration is considered a time of growth and expansion, a time of great discovery, when light was shed on the entire Western Hemisphere. Headed by Columbus' voyage to the Americas, it was the flame that lit the fire of future navigation, technological advancements, and revolutions. Beneath all the growth and glory, however, lies a darker side of the story. When the Spanish conquistadors landed on the shores of Mexico, they brought the diseases of the Old World with them. Did they know of the significance of the role the invisible infection played in their conquest? With the arrival of the Spanish came devastating epidemics, resulting in a massive depopulation of the indigenous people of the New World. Could the Spanish have defeated the strong, vast Aztec civilization without the aid of contagious disease? How would our modern world be different if the Spanish were not victorious in their conquest of the Americas?

The Spanish: Health Problems and Practices of the Old World

By 1450, the Old World was one unified area of disease. Epidemics of smallpox, measles, typhus, and influenza emerged in outbreaks regularly, but in fairly mild forms. The people lived from epidemic to epidemic, blaming their reoccurring illnesses on God. It was the common belief that disease was sent as a curse from above, as punishment for doing wrong against a neighbor. To "be rid" of the sickness, Europeans repented or made amends. They may have then turned to physicians for herbal remedies and cures, afterwards, but religion always played a dominant part in the European health care of the time. Physicians relied on the theory of the Hippocratic Corpus for medical practice. The idea, one from the Greek philosopher, Hippocrates, stated that health was achieved by balance of bodily fluids (blood, phlegm, yellow, and black bile). While herbal remedies may have proved successful, Europe could have been healthier if it was cleaner. The people of the Old World placed little emphasis on sanitation and hygiene, and lived in towns that were the breeding grounds for lice, rats, and bacteria. Unlike their Aztec enemies, the Spanish soldiers were said to have despised washing their clothing, and even more so, taking a nice, long bath!

The Aztecs: Health Problems and Practices of the New World

Prior to the Spanish invasion of 1519, the Aztec people lived in prosperity and health. The Aztecs lived long lives, free from infectious diseases and plagues. Although they suffered mild ailments such as infection from insect bites, amoebae-based diarrhea and fevers, and arthritis in old age, the population bloomed from thousands to tens of thousands in a short time. The common theory for health preservation among the people was sanitation, and cleanliness was clearly emphasized in all aspects of their lives. Aqueducts were built, which provided clean drinking water and an efficient sewage system to the people. A strict code of hygiene was followed by every household member; frequent baths and cleansing salves were a part of daily life. Then, everything changed with the arrival of the Spanish conquistador, Hernando Cortez, in the spring of 1519. Along with his Gatling guns, rapiers, and horses, he brought an unseen enemy: disease. Just as quickly as it rose, the Aztec empire fell when a majority of the population succumbed to the five principal killer diseases (smallpox, measles, malaria, typhus, and influenza) that came with the Spanish.

Smallpox

Smallpox was introduced in the Americas in 1521, when it first struck the capital of the Aztec empire, Tenochtitlan. Transmitted directly from human-to-human, through contaminated exhaled air, or contact with the open sores or clothing of an infected victim, the disease wiped out entire populations, killing nine in every ten people. Those who cared for the victims of the disease soon developed its symptoms of a fever, severe rash, internal bleeding, and blindness. Since the caretakers of the ill contracted the disease as well, later dying, most natives were doomed to death, if not from the smallpox, from starvation.

Measles

Like smallpox, measles in the New World was linked to the domesticated mammals of the Old World. As the Aztecs and other indigenous people became increasingly exposed to foreign animals, they quickly contracted the highly contagious disease. While the virus, which devastated the Valley of Mexico in 1531-1532, killed many, it covered only a small area of land; this disease was so contained because it could only be spread through contaminated air, exhaled by a sick one.

Malaria

In addition to receiving disease exposure from Europe, the New World also became open to the sicknesses of Africa through the slave trade route. One of them was falciparum malaria, a serious and often fatal strain of the illness. Spread by the mosquito, it caused an infection of the bloodstream, and was then easily transmitted human-to-human by another of the common insects. Just as it did in Africa, the mosquito thrived in the humid, wet jungles of the Central American coast, becoming a serious problem of disease to the native population.

Typhus

Similar to malaria, typhus was also transmitted from an intermediary host to humans. Lice, burrowed in the ships of explorers, thrived on the unsanitary conditions present on the Trans-Atlantic Route. Immediately spilling out onto the shores of Mexico, they passed the bacteria-like microorganisms of typhus from person to person by direct contact. This disease spread quickly among the Indian population, and continues to persist in modern Central and South America and Mexico.