Epidemiologists study the patterns, causes and effects of health in populations and begin to look at the life cycle of pathogens (Google Definition). Based on the diverse immunity of a population, the pathogen will spread differently, and affect the population differently. Each individual has a different diverse immunity, but if the population has a combined high immunity rate, the pathogen will not thrive as easily as if the population has a low immunity rate. If an individual is a carrier for a different disease, but it is recessive and non-present the pathogen may respond in different ways within the body. The newly introduced pathogen along with the genetic disorder could create a mutation offspring that will negatively affect the host body (Kilpatrick, Altizer, 2010). Scientist begin making predictions on how the pathogen becomes present. Does the pathogen affect one specific part of the body, or does it attack all of the body? Does the pathogen weaken the immune system? Scientists then use the theory of evolution, and natural selection to make assumptions on the disease. Natural selection allows the pathogen to select for the immune system with the weakest immunity, so the pathogen can have a higher rate of thriving. (Smith, 1978). The selected immune system then acts as a host for the pathogen itself, then the pathogen begins its infectious stage (1978). The pathogen may undergo a mutation within the host …show more content…
The origins of pathogens differentiate based on tropical and temperate conditions, these conditions are relevant to the importance of domestic animals (which can be a originated host for the pathogen) (Wolfe, Dunavan, Diamond, 2007). The pathogen that may have started off affecting only the domestic animal may now affect a human (2007). They then look at the negative affect on the human body and why we can’t fight it off our self with the immunity we already have. They then begin to try and reduce the transmission of the pathogen by taking a test patient and try to find out what trial drug will reduce the effects of the pathogen. Based on what have previously worked on diseases that are less evolutionary advanced than the current pathogen, they will come up with a new drug that will lessen the effects of the pathogen, and increase the strength of the immune system. Scientists also have to consider the population and how the patient and the trial drug will react with the environment. Because most third world countries have low immunity rates due to poor health, they are usually more affected with the disease. With the harsh environment and lifestyle they live, it’s hard to come through with an actual solution or cure to the pathogen that is present in their population. Although epidemic diseases quickly