There are many advantages to living in the age of globalization. Communication around the world is nearly instantaneous, travel time has been reduced dramatically and there are a whole host of other advantages to living in a world with the type of technology that is available today. However, with this free interchange of ideas and the movement of people around the globe comes increased risk for the movement of disease. When disease moves around within a population and is spread by contact between infected individuals, it can quickly become an epidemic. An epidemic is what happens when a certain population begins to show signs or symptoms of a new disease at rates previously unseen in that population (Center for Disease Control 28).
Epidemics that take over populations and occur in the correct circumstances can even become pandemics-- epidemics that exist on the global scale throughout the entirety of the human population. There are different aspects of modern society that contribute to the possibility of new pandemics and epidemics on a massive scale, and without careful consideration of the risks that are posed by new diseases and how to stop their spread, the human population could face some very serious issues in the near future.
Epidemics and pandemics are rarely caused by an infectious agent that has not been seen before. More often than not, epidemics are caused by the mutation of an infectious agent that is already prevalent in the population, making the agent more easily passed from host to host (Center for Disease Control 34). The Center for Disease Control claims that the introduction of an epidemic usually has to do with three factors: first, the mutation or change of an infectious agent like a virus or a bacteria that makes the agent more virulent. Second, the infectious agent is introduced into a new setting, like a population that has no innate resistance to the agent. Lastly, the epidemic may be caused by a change in the host-- perhaps the host becomes more susceptible to the agent for one reason or another (Center for Disease Control 39). This could be due to a coincidental weakness in the immune system of a population due to another outside issue, or even a hereditary condition that is triggered as a result of a mutation in the infectious agent (Center for Disease Control 39).
The other way an epidemic can be spread within a population is through what is known in epidemiology as a propagated outbreak. During this type of outbreak, the infectious agent is spread from individual to individual within a population (“How Epidemics Spread”). This type of epidemic can be caused by a number of different infectious agents, and is not restricted to viral agents.
During a common source outbreak, if the infected individuals are not contained, they can move into the general population and cause a propagated outbreak. If the infectious agent is virulent enough and the method of exposure is common enough, this agent will then spread to other people in the population; once the rates of infection rise, the agent has officially caused a propagated outbreak in the general population (“How Epidemics Spread”).
There are a few different contributing factors to the spread of disease in the newly-globalized world. One of the most important factors is the speed at which people can travel from place to place. Airplanes and airports are incredibly useful vectors for disease in a few different ways.
First, when an individual is infected with a disease, he or she may not become symptomatic for anywhere from hours to days. Some diseases even take weeks or months to become symptomatic; before the disease becomes symptomatic, however, the individual may still be contagious to other susceptible individuals within the population (Mackenzie). If the individual is a carrier of an airborne or contact-spread infectious agent but still asymptomatic, then traveling in close proximity with others on an airplane or within an airport is a fantastic way to spread the disease.
The reason for this is twofold: not only is the individual in close quarters with other people, but all those other people he or she infects are traveling to different locations around the globe (Mackenzie). Each of those people who the original carrier infects will then go on to carry the disease and asymptomatically infect a variety of other individuals before the disease can be recognized as an epidemic (Mackenzie).
Even if an individual is symptomatic, if the symptoms are not severe, they may be misunderstood as merely symptoms of a cold or other mild illness. The illness or infection may progress later, but being in close physical proximity to people in an airport or in an airplane is, once again, problematic because it allows the infectious agent to spread to locations that it may not otherwise be able to reach (Mackenzie).
In addition, the air recycling system inside planes are particularly conducive to passing airborne infectious agents between individuals on those planes; it is one of the reasons that it is so common for individuals to become sick after they fly for long periods of time on airplanes (Diamond).
Another issue that the globalized world faces that is new is the emergence of cities. In the twentieth century, more people were living in urban centers than in rural locations; this is great for things like technological advancement and ease of transport, but it also means that millions of people come into close contact with each other every day (Larson). When an infectious agent is airborne or spread via skin-to-skin contact, this can mean a particularly virulent agent can be spread extremely quickly within urban centers.
This issue of particularly virulent infectious agents is compounded in urban centers because urban centers often play host to airports and other modes of transportation that can easily move the infectious agent out of the urban center in which the outbreak began (Rubin). This poses a particular problem for individuals who are responsible for containment of the infectious agent, especially when the agent crosses international borders and the issue becomes an international diplomacy issue (Rubin).
Containment is one of the most important issues that experts wrestle with when it comes to epidemics and pandemics. Containment of the infectious agent within a population that has already been exposed is really the only way to keep the agent from spreading to the entire population, barring the invention of a vaccine or other cure for the disease that the agent causes (Rubin). In the past, containment was much easier; for instance, the plague in Medieval times was contained to Europe because it took too long for anyone to carry the plague outside of Europe and infect other areas of the world (Rubin). Today, the bubonic plague could easily have spread around the world because of the ease and speed of travel.
Containment does not need to be a physical containment, however. Certain infectious agents, such as the Human Immunodeficiency Virus, or HIV, are spread only through fluid contact between individuals, often sexual contact (Rubins). To contain the spread of HIV, infected individuals need to avoid having any kind of fluid exchange with uninfected individuals; however, infected and uninfected individuals can travel freely near each other with no danger of spreading the virus (Rubins).
The HIV epidemic is actually considered a global pandemic, because it affects human populations around the globe (Diamond). It is one of the most common sexually-transmitted infections, and has no known cure or vaccination. HIV became known to scientists in the 1980s, where it was slowly becoming prevalent among members of the homosexual male community (Center for Disease Control). However, the virus quickly spread to the heterosexual community, and today, the virus does not discriminate (Center for Disease Control). Because it is spread by fluid exchange, the HIV virus is somewhat different from the theoretical epidemics that have been discussed previously.
An individual needs to come into close, fluid-to-fluid contact with an infected individual to become infected with the HIV virus. In the past, this type of infection would have led to a very slow rate of infection in various populations around the world, because the slow rate of travel and relatively low potential for infection between individuals who have casual contact (Diamond).
However, today, individuals can travel anywhere in the world very quickly, and engage in sexual behaviors in many different places with many different partners, often before they begin to show signs of AIDS (Diamond). In addition, drug therapy has increased the lifespan of individuals with HIV-- it can take decades before the HIV infection becomes AIDS, giving individuals who are infected a lot of time and potential for infecting other individuals in many different places around the world.
The HIV pandemic is a unique pandemic, because it is a quiet one. Nearly no one dies from HIV or AIDS; instead, individuals with the disease become so immuno-compromised that they die from complications, often fairly innocuous diseases like influenza or pneumonia (Center for Disease Control). There is nothing dramatic about an HIV infection; people with HIV rarely begin to show outward signs of the disease if they are receiving treatment. This is why very few people outside of scientific circles recognize that HIV is, indeed, a global pandemic and a huge threat to the human population as a whole.
A completely different type of pandemic from the HIV pandemic would be a potential hemorrhagic fever epidemic. Hemorrhagic fever, often caused by the Ebola virus, is a type of disease that is also usually spread by fluid contact (Center for Disease Control). The different hemorrhagic fever viruses often begin with influenza-like symptoms, but victims quickly deteriorate to the point where they are hemorrhaging blood from various bodily orifices (Center for Disease Control). According to the Center for Disease Control, in as many as half of the documented cases of hemorrhagic fever, patients began to bleed from mucus membranes and any break in the skin (Center for Disease Control).
Because most forms of Ebola and hemorrhagic fever that are known to the medical community today are passed via fluid exchange, the various Ebola viruses make a good parallel to the HIV pandemic. Although there has never been a true outbreak of Ebola, there have been small, localized outbreaks throughout various locations in Africa (Rubin).
During these outbreaks, the virus tore through populations; Ebola Zaire, one of the known forms of the Ebola virus, killed upwards of ninety percent of the individuals that were infected with the virus (Rubin). If this virus were to emerge in a major metropolitan area, the consequences of the exposure would be disastrous to the human population as a whole. The only upside to the Ebola virus is that the incubation period for the virus is relatively short; people become symptomatic rather quickly, and the form of the virus that affects human beings is bloodborne rather than airborne. However, if the virus were to mutate and become an airborne pathogen, the virus could very easily spread to every corner of the globe within weeks, wreaking havoc on the human population (Rubins).
One of the problems with pandemics and epidemics is that the threat of disease often causes panic. People who are within a containment zone, for instance, may make attempts to escape the containment zone out of fear of becoming ill, when the best thing for the population at large is for all those who have been exposed to stay within a containment zone. People leaving the containment zone, whether it is a physical containment zone or a restriction on fluid interchange can cause the spread of the disease to other individuals. It only takes one infection outside the containment zone to continue to spread the infection throughout the entire available population-- and globalization has ensured that the entire available population of human beings is available for any potential infectious agent.
The changing face of the globalized world has changed so many things for humanity. The rise of technology has provided humanity with a standard of living that is much higher than it has ever been before. However, globalization and global travel has also brought about the potential for untold catastrophe in terms of the potential for epidemics and pandemics in the general human population.
In Asia, there is a rising fear of epidemics and infectious disease because of the population density of the area. Every year, new diseases are said to be spreading throughout the population, although few have caused any kind of real problems. However, there is the definite possibility that someday a new infectious agent could emerge that thrives perfectly in the conditions created by globalization.
Center for Disease Control. Emerging Infectious Diseases. Atlanta: National Center for Infectious Diseases, 2006. Print.
This CDC report discusses a variety of different diseases that have faced humanity in recent years, and some diseases that are likely to face humanity in the near future.
Diamond, Jared M. Guns, Germs, and Steel: The Fates of Human Societies. New York: W.W. Norton &, 1998. Print.
Jared Diamond’s book is about the way that culture has changed and been formed by the existence of guns, germs, and steel, particularly in the ways that the Western world has developed differently from the rest of the world. This is not as scientific as other pieces, but it is a well-known and well-documented piece.
Larson, Elaine. "Community Factors in the Development of Antibiotic Resistance." Annual Review of Public Health, 28. (2007): 435-447. Print.
Antibiotic resistance is a growing problem, particularly in hospitals and places where sick people gather for courses of antibiotic treatment. Larson looks at the different factors contributing to antibiotic resistance.
Mackenzie, Deborah. "Pandemic-causing 'Asian flu' accidentally released." New Scientist 2005: Print.
Mackenzie examines the accidental release of a flu virus into the population and the effects of the virus on the population. The analysis is qualitative and quantitative in nature.
Rubin, Ph.D., M.D., Harvey. Future Global Shocks: Pandemics. OECD, 2011. Video.
TED. Ted Talks: How Pandemics Spread. Digital video. 2010. Web. 20 March 2013
This is a basic overview of the effects of a pandemic, and the different types of pandemics. It is given by a doctor, but uses language that a layperson can easily understand.