HUMAN BIOLOGY

Human Biology

Question 1

Transmission and Development of Infection

Cholera

Vibrio cholera, a bacterium, causes the infection known as cholera. It is generally prevalent in South America, Central America, Africa, Middle East and in some regions of Gulf Cost as well as in Asia.

Transmission

It is caused due to the ingestion of the contaminated food. The food or water is particularly polluted with fecal material, of the infected individual, has the potential to cause cholera. The ingestion of seafood which is not properly cooked may cause this infection. The viable cholera bacterium is usually excreted in vomiting as well as in feces where they are capable to survive for fifty days. Moreover, it is best live in aqueous animals such as plankton, algae and shellfish (CDC, 2002).

Life cycle

Vibrio cholera completes its cycle in two phases, in water outside the body of the host and further inside the host body. The entire life cycle is demonstrated in the picture below

Figure 1 Life cycle of V cholerae involves both environmental and human segments (David et al, 2004, pp. 29)

In aquatic phase, the free swimming vibrios become viable following the alteration in their genetic composition. These strains get bonded to the aquatic bodies and cause cholera in the human body if consumed unfiltered and untreated. After reaching the epithelium of the small intestine, toxin of cholera releases due to the proliferation, and thus causing diarrhoea. In this way, the vibrios come back to the environment and the cycle continues.

Prevention and Treatment

The preventive measures encompass the assurance of safe water provision, proper sewage and sanitation systems, and recommendations regarding thorough cooking of sea foods particularly. Public education, through mass media, is also crucial to improve the habit of drinking using boiled water or the sealed bottles, as well as the avoidance of peeled vegetables and fruits.

Hydration is the foremost step in the treatment of cholera along with the antibiotics. The Centre for Disease Control and Prevention (2013) has recommended Doxycyclin as the first drug choice for the treatment of cholera. The alternate medication is a tetracycline while erythromycin is a drug of choice for children.

Athletes Foot

Athlete foot is the fungal infection caused by trichophyton. The athlete foot mainly results from the fungus dermatophytes which grow in the moist areas even of the body.

Transmission

There are various modes of its transmission such as through the link with tainted pool, gym, floors and contact with infected individuals or their daily using stuff like shoes, socks, and else.

Figure 2 Life Cycle of Trichophyton

Trichophyton asexually reproduce through mycelium and produce reproductive spores. These spores are produced as clusters such as grapes. These spores enter the body cells and cause Athlete`s foot.

Prevention

Proper hygienic condition of foot, drying the foot particularly between toes after washing and acquiring the habit of wearing clean socks and shoes; greatly aid to control the disease. The antifungal ointments and powders are used to cure the infection (AF, 2000).

Malaria

It is resulting from the parasite plasmodium, which enters the human body through ...