In addition, viruses also utilized this docking system in order to attach to host cells. Obvious exceptions exist which include the rabies virus. For example, in the rabies virus, the docking and transmission between species are able to occur because the rabies proteins tend to match many species (Daempfle, 2016). Furthermore, some viruses have tail ends, which enable them to …show more content…
This exception occurs when mutated forms of viruses change enough to cross over and in return, infect a new species. Scientists tend to believe that this occurred in the spread of acquired immunodeficiency syndrome (AIDS), which is caused by the human immunodeficiency virus (HIV) is an example of a non-species specific disease (Daempfle, 2016). In this instance, the HIV virus was mutated from nonhuman primates in sub-Saharan Africa (Daempfle, 2016).
Another example of a diseased caused by viruses in humans is smallpox. Smallpox is an acute contagious disease that is caused by the variola virus (Smallpox, n.d.). Deemed as one of the world’s most devastating diseases known to humanity, smallpox is transmitted from person to person via infective droplets during close contact with an infected symptomatic person. Overall, smallpox is not known to be transmitted by animals or insets and there is no asymptomatic carrier state (Smallpox, n.d.).
Finally, the rabies virus is a deadly virus that is spread to people from the saliva of infected animals. Typically, the rabies virus is transmitted through a bite. Once a person presents signs of symptomatic behavior, the disease is nearly always fatal. It is for this reason that anyone that has a risk of contracting this virus receives the rabies vaccination for