- Homo sapiens
- Sarcoptes scabiei
Sarcoptes scabiei utilizes the upperdermis of humans to produce eggs and to travel from host to host. Parasite species is located globally with no specific interest in race, socioeconomic class, and climate. Reported cases are estimated at at least 300 million annualy . Symptoms of infection involve an extreme itchy feeling that produces rashes and sores.
Sarcoptes scabiei and Host Description:
- This parasite is responsible for an infection known as scabies. This tiny mite’s name is derived from scabere, the Latin word meaning to scratch . Sarcoptes scabiei is an ectoparasite in which humans serve as the only host .
- Sarcoptes scabiei possess a relative simple life cycle compared to most parasites. These mites wander on the surface of your skin to find a suitable place to burrow into. Once the females are in place they release eggs, generally 2-3 which hatch in approximately 4 days. Upon hatching, a larva emerges which will become a nymph after several moltings. Continuous moltings lead to the adult form .
courtesy of: http://www.dpd.cdc.gov/dpdx/HTML/Scabies.htm
- This parasite causes an infection, but not necessarily a disease. Recall that an infection is basically the body’s initial reaction to the pathogen. In this case, inflammation of the epidermis as a result of prolonged scratching is the main symptom of Sarcoptes scabiei.
An Example of True Parasitism:
- Up through current lectures in parasitology, we are slowly approaching a clearer definition of a parasite. A parasite usually benefits from it's host, while the host is left at a disadvantage. The parasite, upon successfully establishing a foothold in the host, has not only shelter and nutrients, but most importantly a place to reproduce and to pass beneficial genes to the next generation. The debilitated host, in the case of harmful parasites, now has to cope with the infection. If an individual with a case of scabies is infected, the parasite obtains a place to disperse offspring as well as the potential to travel via human skin to skin contact.
Future Questions and Observations:
-Upon describing this parasite, one might wonder why this parasite is harmful if it doesn't for the most part actually penetrate and live inside the body. What must be taken into consideration is the location that the parasite utilizes. Eventhough only our upperdermis is affected, humans depend on the the integumentary system especially the skin as our first line of defense against pathogens. When the skin is utilized by this species, the skin is left in a reduced state thus making the host more suspectable to other foreign invaders. Superficially, no pun intended, their is no harm done, but what happens to the female mite upon death? Does it simply just blow away and the skin fills in the hole like modern Departments of Transportation fill in holes on the highway, or does the carcus become a nest to other microorganisms?
-Perhaps another question that can be addressed is why humans are the only organism in which this host can infect.
3.Hicks MI. Elston DM. Scabies. Dermatologic Therapy. 22(4): 279-292. 2009