Part 2: The Swarm Summary
Last Updated on June 8, 2022, by eNotes Editorial. Word Count: 1016
Haskell County is a farming community in rural Kansas. Evidence “suggests that a new influenza virus originated in Haskell County, Kansas, early in 1918.” The virus then traveled to Camp Funston, a large army base. From there, it spread around the world.
The evidence tracing the 1918 pandemic to Haskell County was collected by Dr. Loring Miner, an “isolated country doctor” who, despite the rudimentary condition of medicine at the time of his training, had kept up with changes in the field and even built his own laboratory. Early in 1918, Miner treated patients suffering from a new and violent influenza; even though the disease disappeared, Miner submitted a formal warning to national public health officials.
Three hundred miles away, Camp Funston held an average of fifty-six thousand new troops. Like many army bases, Funston was overcrowded, with insufficient clothing and heat for the men. In March 1918, influenza spread throughout the camp. Although it was more severe than the initial outbreak in Haskell County, it was not as deadly as the pandemic that would follow.
From Funston, “a constant stream of men” flowed to other American bases and to Europe.
It is not known for certain if the 1918 influenza pandemic originated in Haskell County. While other theories exist, the theory that Haskell County is the pandemic’s place of origin is supported by many scientists.
To understand the spread of the virus, “one must first understand viruses and the concept of the mutant swarm.” Viruses are “an enigma that exist on the edges of life.” They are not independent organisms able to function on their own, and there are different theories of their origins.
A virus relies on its host to perform its single function: to replicate itself. Through its genetic makeup, a virus invades another cell, subverts it by inserting its own genes into the cell’s genome, and forces it to produce new viruses. The physical structure of a virus is critical to understanding it. Through the physical forms in the body—“cells, proteins, viruses, and everything else”—different forms fit together, reactions occur, and messages are communicated.
Influenza viruses originate from wild birds, and there are three different types: A, B, and C. When an influenza virus adapts to humans, “it will threaten a pandemic.” In humans, influenza attacks the respiratory system and has indirect effects on other parts of the body. Influenza appears as an endemic disease—a disease that “is always around”—and also appears “in epidemic and pandemic form.”
Due to their structure, influenza viruses bind to the cells in the respiratory system. A virus “hides from the immune system” by entering the cell. When the cell explodes, “a swarm of between 100,000 and 1 million new influenza viruses escapes.”
One of the reasons influenza viruses are so dangerous is their ability to quickly adapt. The influenza virus has simple genetic information carried on RNA, not DNA, making mutations much more likely. When a virus explodes, it does not just spew out exact replicas of itself; instead, it spews out a “mutant swarm” of slightly varied versions of itself.
Many of these versions are useless, carrying mutations that make them unable to infect another cell. But some of these mutations might do the exact opposite, changing the virus to make it adaptable to a different species, to make it more severe, or to make it resistant to drugs.
The body’s defense against viral infections is the immune system. The immune system is complex, with many different parts. The “key to the immune system” is its ability to determine what “belongs in the body… from what does not.”
The parts of the immune system—white blood cells, enzymes, antibodies, and others—patrol the body by circulating through it, searching for “nonself” markings as they interact with other elements in the body. If a “nonself” marking is found, the immune system attacks. The physical markings that stimulate the immune system are called antigens. When dendritic cells, a type of white blood cell, discover a foreign antigen, they carry these antigens to the spleen or lymph nodes to inform the rest of the immune system. In response, the body releases enzymes and produces large numbers of antibodies and white blood cells that “will attack the target antigen.”
This mobilization is called “the immune response.” If and when a new infection is defeated, “memory T cells” and antibodies remember the specific antigen. This allows the immune system to respond much more quickly if the same antigen is ever encountered again.
The influenza virus evades the immune system in several ways. First, its chief antigens mutate quickly, making it “impossible for the immune system to keep pace.” Barry explains how “antigen drift” can create epidemics by making it more difficult for the immune system to recognize and bind to the virus. Pandemics, however, occur when there is an “antigen shift.” This time, the immune system is entirely unable to recognize and attack a virus. Antigen shift is what allows a virus to jump from birds to humans. When a person or animal is infected with two variants of the virus, a “hybrid virus” can be created, increasing “the chances of a virus jumping from one species to another.” Pigs, with their ability to be infected with both avian and human viruses, are thought by some scientists to be a perfect “mixing bowl.”
Throughout history, antigen shifts have caused pandemics to sweep the globe. At different times and in different countries, governments have slaughtered millions of chickens or pigs in an attempt to contain new diseases.
Another uncommon feature of the influenza virus is its “cannibalistic” nature. When influenza stimulates the immune system, older versions of the virus usually become extinct. This feature “helps prepare the way for a new pandemic, since the more time passes, the fewer people’s immune systems will recognize other antigens.”
Antigen shift caused three different pandemics in the twentieth century. Whenever an antigen shift occurs, it “guarantees that the new virus will infect huge numbers of people, but it does not guarantee that it will kill large numbers.”