Diseases and plagues have been a part of humanity since the beginning of time. They are known for mass suffering, pain, and death. There are many historical examples of how and when diseases and plagues began. In addition, there are several modern issues that perpetuate diseases and plagues.

There were many cultural and societal factors that lead to the rise and spread of diseases and plagues. Originally, most societies were based on hunting and gathering food. These societies were usually small and moved regularly. Disease was generally spread only among the small group, and most diseases were probably the result of parasites.
Around 8000 BCE, societies began to change. Many began to settle down in one spot and create communities. Instead of hunting and gathering, people began to engage in agriculture and the domestication of animals. Consequently, the human population grew rapidly.

But with this time of great prosperity came unforeseen consequences. The closer proximity to animals brought about diseases that were spread from animal to human, known as zoonotic diseases. Larger populations meant disease was spread more quickly. More human hosts also allowed disease to change more quickly. This led to the “crowd diseases,” such as measles, tuberculosis, smallpox, and influenza. Some people did not show symptoms of these diseases and were asymptomatic carriers (such as Typhoid Mary much later in history). Larger populations also created more waste and trash, leading to squalor. This acted as a petri dish for disease and harbored disease vectors like rats, mice, lice, and flies. Clearing land for agriculture often displaced other disease vectors, like mosquitoes or the tsetse fly. Irrigation systems for crops could lead to parasite breeding, as was the case in Egypt with Schistosomiasis.

As humans began to create more advanced societies and trade with one another, plagues followed them. The Roman Empire fell victim to the Plague of Antonine (165-180 CE), which was an outbreak of smallpox. In addition, the Romans underwent the Plague of Justinian (541-757 CE), caused by the plague bacillus Y. pestis. This plague never truly left Europe and popped back up in 1346 as the Black Death. This plague followed trade routes all throughout the Europe and Asia. These are only a few examples of documented plagues throughout history, but there are countless others not mentioned here.

Plagues and disease are not gone from us today. There are many modern factors today that foster the spread and development of diseases and plague. One factor is global climate change. The warming of coastal areas has been related to an increase in cholera outbreaks. Also, hotter temperatures have been correlated with more hospital visits, as well as more extreme weather phenomena, which may impact health.

Another factor is the relatively recent boom in population size. As seen in ancient times of population growth, disease becomes spread more easily, and diseases are more likely to develop new strains. In addition, with more people, there are less resources for all. This can lead to poverty, which has been shown to be related to instances of disease.

With increased technology and efficiency in day to day life, humans have more leisure time than ever before in history. This can be detrimental, though, because it has led many to be less active. Less activity results in less calories burned, leading to a calorie excess. This can often lead to obesity, which we see more and more of today, especially in America.

Warfare has been with us from the beginning and is still strong today. The existence of disease and potential plagues can be directly related to warfare. Take Yemen, for example. Yemen has never had the best healthcare system, but after years of war and repeated targeting to healthcare and water treatment facilities, it is destroyed. This has led to cholera outbreaks and diphtheria. Warfare greatly impacts human health, especially in regards to disease.

Even advances in healthcare have caused potential health risks. The increased use of antibiotics has led to antibiotic resistance in different diseases. Recombinant DNA technology can lead to a lot of good but can potentially facilitate the development of super-strains of diseases. One advance that will help prevent disease and plagues is that health information is now more readily available to the public. This can allow people to better manage their own health.

Diseases and plagues have been with humanity from the beginning, but different factors have influenced their impact over time. Factors today are mostly different from ancient times, but some remain the same. Ultimately, we must do our best to mitigate these factors and halt the spread of disease and plague where we can.

References: Disease and Famine as Weapons of War in Yemen, The Price of Being Sedentary PPT, https://www.ancient-origins.net/news-mysterious-phenomena/justinian-plague-probably-caused-bacteria-unknown-how-it-appeared-00438 for image 1, https://emtv.com.pg/yemen-cholera-outbreak-kills-25-people-in-a-week-who/ for image 2