What Diseases Mean in the Modern World

[Guest guest]

What Diseases Mean in the Modern World

By Shulman, Posted January 3, 2008

While often overlooked, disease has had important influences on the

development of society through the course of history. U.S. News spoke

with Irwin Sherman, a professor emeritus of biology at the University

of California-Riverside, about his new book, Twelve Diseases That

Changed Our World, and some of the devastating dozen it names.

How did you decide which diseases to feature in the book?

The choices of the 12 diseases in this book were somewhat arbitrary. I

chose diseases that I felt had made a significant impact not only on

the population and not only on history, but that there was some [good]

that was obtained from it. I chose yellow fever as well as malaria

since both were important [inspirations for improving mosquito]

control. But there may have been other diseases that I could have

chosen but didn't—let's say sleeping sickness, which has probably

prevented much of the exploration and development of Africa.

In the United States, most people haven't experienced widespread

pandemics, but other countries still struggle with malaria,

tuberculosis, and even measles. How is this affecting their development?

I think that many of these countries are hampered in their economic

development as a result of infectious diseases. They place a

tremendous burden on the societies. Consider someone infected by

malaria. There will be great absenteeism and lethargy, then there's

the burden on the healthcare system. The same thing is true of

HIV/AIDS—you lose valuable members of the population; parents are

lost, schoolteachers are lost, and so are ordinary workers, which

makes productivity decline.

A year or two ago, people spoke in fear of avian influenza. Before

that, there was SARS. What's the next world-changing disease likely to be?

It's very difficult to say. I don't think anyone would have predicted

SARS. Most people believe that continuing contact with animals—and

this has been historically true—will result in diseases jumping from

one species to another. Having domesticated and wild animals in close

contact with human populations will probably result in this. We've

seen this before with hantavirus, a rodent disease. Whether they will

be of the magnitude of an influenza or even SARS remains to be seen,

[but] we're better prepared for some of these than we have been in the

past. There's a great boon in understanding the [infectious] nature of

the agent. Imagine SARS appearing 300 years ago and the panic that

would have occurred.

Many of the nasty microbes you wrote about spread through the movement

of people—whether for war, trade, or settlement. How do you envision

increasingly globalized trade, the ease of world travel, and fluxes of

refugees and immigrants influencing future disease outbreaks?

I think they all accentuate the emergence of disease. Yellow fever was

transported from Africa to the Americas in cisterns on ships because

the mosquito could breed in them. Back then, an infected individual

would probably die on the ship. Today you can travel from one country

to another in a matter of hours. In San Diego, there are always

introductions of malaria from Mexico and Central America and from

India. But these don't cause epidemics because the numbers are few,

the diagnosis is usually pretty quick, and we have reasonably good

drugs that can control the disease. Nevertheless, it still represents

a threat.

http://health.usnews.com/articles/health/2008/01/03/what-diseases-mean-in-the-mo\

dern-world.html

12 Diseases That Altered History By Shulman

Posted January 3, 2008

It's often taught that the course of history hinges upon great

battles, both in war and among competing ideas. The stars are a few

powerful individuals—presidents, monarchs, dictators—whose actions can

shift a society's development one way or another. But some influential

actors are nasty and ruthless—and microscopic. In his book Twelve

Diseases That Changed Our World, Irwin Sherman, a professor emeritus

of biology at the University of CaliforniaRiverside, describes how

bacteria, parasites, and viruses have swept through cities and

devastated populations, felled great leaders and thinkers, and in

their wake transformed politics, public health, and economies.

U.S.News & World Report spoke with Sherman about how 12 key

diseases—smallpox, tuberculosis, syphilis, AIDS, influenza, bubonic

plague, cholera, malaria, yellow fever, two noninfectious diseases

(hemophilia and porphyria), and the plant disease behind the Irish

Potato Famine—have altered history.

Sherman also answered our questions about how the threat of disease

outbreaks is affecting our world today.

Smallpox. It's the only infectious disease that has been eradicated

through vaccination. The medical science of vaccination was a direct

result of the devastating effects of smallpox. Essentially, studies of

immunity and vaccines emerged from studies of smallpox. That gives

hope that other diseases, too, will be eradicated by similar means.

Tuberculosis. The struggle against TB stimulated some of the first

quests for antibiotics. The disease most likely promoted

pasteurization, which heats and kills TB and other pathogens that can

contaminate milk. The infectious nature of tuberculosis also prompted

the building of sanitariums, where people could be isolated and treated.

Syphilis. Once treated with heavy metals like mercury, which had

devastating effects on patients, syphilis inspired the discovery of

chemotherapeutic agents. The sexually transmitted disease prompted

chemotherapy pioneer Ehrlich to look for what he called a magic

bullet, which turned out to be the drug salvorsan. The history of many

drugs can be traced to Ehrlich's work with dye materials that stained

not only fabrics but organisms as well, spurring him to look for drugs

that could bind to and kill parasites.

HIV/AIDS. " You can't talk about infectious diseases without discussing

AIDS, " Sherman declares. While today's chemotherapy cocktails—when

available—are effective at reducing the number of AIDS-related deaths,

it's a disease that also can be controlled by what he calls the most

difficult intervention: behavioral control. " It's also a disease that

is modern and yet has its parallels with the past in the kind of

reactions that populations have when there's an unforeseen epidemic, "

he says.

Influenza. Few diseases have had such widespread effects on the number

of deaths in the modern world as the flu, which remains a major threat

worldwide despite the existence of vaccines against it. The disease

very likely influenced the course of World War I by sickening and

killing soldiers and straining military healthcare systems. Some have

suggested that President 's negotiations during the Treaty of

Versailles were affected by the influenza infection he had at the time.

Bubonic plague. Quarantine—the isolation of infected or potentially

infected people as a way to stem the spread of disease—developed from

Europeans' long and storied history with bubonic plague. Sherman notes

parallels between popular reactions to the plague in medieval times

and reactions to HIV/AIDS in the modern era. Fear and ignorance,

anxiety, prejudice, isolation, and panic can all result from not

understanding the nature of a disease, he says.

Cholera. Spread via paltry or nonexistent sewage systems and lack of

clean water, cholera was—and still is—rampant in many parts of the

world. But improvements in sanitation have reduced cholera's impact in

a number of regions. The power of epidemiology allowed 19th-century

English physician Snow to deduce that the disease was present in

the water, even though the bacterium wasn't identified until many

years later.

Malaria. One of the most lethal infectious diseases in history,

malaria causes over 300 million cases worldwide and up to 3 million

deaths a year. It's one of the earliest examples of the importance of

controlling vectors—animal or insect carriers (in this case,

mosquitoes)—in preventing the transmission of disease. One of the

reasons Europeans managed to colonize Africa, according to Sherman,

was that they utilized quinine, an antimalarial drug derived from the

bark of the cinchona tree.

Yellow fever. Although vanquished in some countries, this

mosquito-borne disease hasn't been eradicated and probably never will

be, says Sherman. The disease influenced the building of the Panama

Canal, the Louisiana Purchase, and, in fact, the pre-World War II

development of the southern United States. " The stereotypes of the

lazy, drawling southerner and the energetic, bright northerner were

typical characterizations due to disease or the absence of disease, "

Sherman says. " In the North, mosquitoes couldn't survive

overwintering, so there wasn't yellow fever. In the South, on the

other hand, you had a population that was either decimated or

debilitated by the disease. "

Hemophilia and porphyria. As genetic blood disorders, hemophilia and

porphyria had serious effects on the crowned heads of Europe.

According to Sherman, the rise of Spanish dictator Francisco Franco

can be traced to the lack of an heir to the throne because of

hemophilia. Another example is the collapse of the Romanov dynasty in

Russia, which was due to hemophilia in the family. The czar was

debilitated and couldn't take over, setting the stage for the rise of

the Bolsheviks.

Many of the British monarchs were unable to manage their kingdoms

because of porphyria, which can cause a variety of mental problems,

like hallucination, paranoia, and anxiety. Some describe III's

treatment of his American subjects, which helped to trigger the

American Revolution, as being in part affected by his porphyric attacks.

Potato blight (cause of the Irish Potato Famine). Sherman expanded the

range of maladies to indicate to readers that diseases affect not only

humans but also sometimes what we eat. Potato blight had a profound

impact because it devastated a staple food that fed much of Ireland in

the mid-1800s. Other plant diseases could have similarly far-reaching

consequences today, says Sherman. Many agricultural economies focus on

a particular crop, so a single disease could be a big threat—and a

major historic force. The Irish famine influenced America by

generating an influx of Irish immigrants to U.S. cities; those

newcomers expanded the Democratic Party, participated in the

development of labor unions, and molded the nation's character in

numerous other ways.

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tory.html