How do humans contribute to the emergence of new infectious diseases?

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How do humans contribute to the emergence of new infectious diseases?

There are several factors that contribute to the emergence of new infectious diseases. The Centers for Disease Control has done extensive research of these new illness. The CDC describe agricultural development is one of the common ways human contribute to the problem. With over 7 billion people on the planet, there is a need for additional food sources. Rodents and other animals spread disease in areas where large farming operation are located. Human population movement especially where there is civil unrest or war. Therefore, areas where people are struggling under those conditions are prone to spread of disease. Especially, when there are no resources or medical supplies available to treat infected people. International travel also a role in the spread of new infectious diseases. More people travel to various parts of the world where infectious diseases are not treated in a timely manner or not vaccinated prior to travel to prevent the spread of disease. Other contributing factor is the breakdown of public health infrastructure and measures to fight infectious diseases. Low income countries with poor sanitation and polluted water supplies are susceptible to infectious diseases. The CDC reported that cholera is reemerging in South America and Africa due to this situation.