The routes of infection spread are chiefly by means of pathogenic agents. These can spread from animal to animal or human to human by a variety of transmission modes (Hurst, 1996, pg.9). Microorganisms are transmitted through several routes, namely contact transmission, droplet, airborne transmission, and vector borne (Hurst, 1996, pg.9). Human exposure can occur by direct contact transmission, which involves contact with a pathogenic agent or organism from an infected animal, through open wounds, abraded skin or mucus membrane. There is a droplet form of spreading, which happens as droplets that have micro organisms are produced from a contaminated being by air and may be through coughing, talking or sneezing. Airborne transmission occurs by the spread of airborne droplet nuclei of evaporated droplets containing microorganisms or through dust particles containing an infectious agent (Hurst, 1996, pg.10). Vector borne transmissions are those diseases transferred by an arthropod or insect vectors, such as mosquitoes, fleas or ticks.
No one is at fault for spreading of infectious diseases. The Introduction of the agent into a new host population (whether the pathogen originated in the environment, possibly in other species, or as a variant of an existing human infection), followed by establishment and further dissemination within the new host population “adoption” may cause this (Hurst, 1996, pg.15). Human behavior can have important effects on disease spreading. The best-identified instance is sexually spread infections and surfacing of HIV. However, this is not constantly the case, and normal ecological alterations, such as weather or climate variance might have similar outcomes. A means of preventing the infection is through immunization, where one is either given an injection or exposed to the disease-causing microorganism (Hurst, 1996, pg.29).
Hurst, C. J. (1996). Modeling Disease Transmission and Its Prevention by Disinfection. Cambridge: Cambridge University Press.