New diseases spring up on a regular basis. Almost all of the pathogens that are deadly to humans derive from zoonotic sources “animals” were an disease that animal has mutates and infects a human. Diseases like H1N1, SARS, and Smallpox to name just a few all started as a zoonotic disease. These types of pathogens didn’t just fly in the wind and randomly infected humans, it began from the slow development of humanity itself.
In the prehistoric ages, humans were hunter gatherers were they migrated regularly and had little to no contact with any other group of humans. The groups had a low birth rate and little diversity. Even if a disease broke out, it would not travel far because the group of infected would die off before they came in contact with other humans. According to the powerpoint between 8000 BCE to 1750 CE the population increased 160 times to 800 million. Once the agricultural revolution began, humans began to settle due to the availability of food sources. More food meant more humans and due to a lack of sanitation or healthy habits humans, animals and all of their feces were all in close proximity of each other. Disease was easily transferred to a human host from an animal and even easier from human to human. This type of epidemics recurred throughout history and it happened everywhere in the world. In the prosperous egyptian civilization mummies provided evidence of smallpox infections. The Black death that swept through Europe was Yersinia pestis. Influenza took hold of the United States in the early 1900’s claiming millions of lives. The industrial revolution brought the biggest population boom in history and continue the human race to a rate of exponential growth. With more humans, there are more ways for a pathogen to continue to spread itself and with a increasingly interconnected world it has become that much easier.
Globalization has made it possible to travel anywhere in the world or communicate with anyone. More humans having more contact with different environments and more stress and damage being caused to the environment. Climate change can have an effect on the likelihood of a pathogen mutating. If the animals in the environment have to adapt, their disease will too. In turn, their illnesses became increasingly deadly towards humans. This was evident with the H1N1, SARS and Ebola outbreaks. The question is not if a major epidemic like the black death will occur, it is when. All of the elements are present for a pathogen to mutate and take hold of the human population spreading like wildfire. The best line of defense will be prevention and recognition of anomalies.