Epidemiological Triangle

In this paper, I will discuss the epidemiological triangle, the protozoan Giardia, and the helminths Loiasis. The Epidemiologic Triangle is a traditional model developed by scientist to study infectious diseases (CDC 2018). The triangle has three vertices that consist of an agent, a host, and an environment. Giardia is microscopic parasite that causes a diarrhea illness known as giardiasis (CDC 2015). Giardia is the most common cause of parasitic gastrointestinal disease. Using the epidemiologic triangle as follows for Giardiasis:

Agent- Giardia lamblia (also known as Giardia intestinalis or Giardia duodenalis)

• A flagellate protozoan.

• Although the parasite can be spread by different ways, water is the main mode of transmission.

• Giardia can survive outside the body and in the environment for long periods of time since the parasite is protected by an outer shell (CDC 2018).

• Can be found in the United States and around the world.

Host- Humans and/or animals infected with Giardia

• The parasite lives in the intestines and is passed in feces. Anything

that comes in contact with feces from an infected human or animal can become contaminated with the Giardia parasite.
• Although this microbe takes lodging within animals and humans these hosts may or may not know they are infected with Giardia.

Environment- Inadequate sanitation such as bathroom handles, changing tables, diaper pails or toys that contain feces from an infected human or animal. Inadequate treatment of drinking water.
• Giardiasis can be spread by ingesting uncooked food containing Giardia as well as swallowing water from sources where Giardia live such as untreated or improperly treated streams, lakes, or wells.
Helpful tips on preventing Giardia:
• Washing hands (Minnesota Department of Health 2017).
• Avoid drinking recreational water (Minnesota Department of Health 2017).
• Avoid fecal exposure (Minnesota Department of Health 2017).

Classified into phyla Aschelminthes (roundworms) and Platyhelminthes (flatworms) are two types of helminths (Nelson and Williams 2014).

Whereas other invade organs including blood, liver, lungs, subcutaneous tissue, and brain many of these organisms live only in the intestinal tract of a parasitized host. These parasites are also called large microscopic organisms. Loiasis is an infection caused by a parasitic worm known as Loa Loa (CDC 2015). This parasite is known as the African eye worm by most people (CDC 2015). Since the presence of people with Loa Loa infection has limited programs to control or eliminate lymphatic filariasis (elephantiasis) and onchocerciasis (river blindness) whether a person has Loa Loa infection has been more important in Africa. In Central and West Africa 29 million people are more at risk of getting Loiasis in these areas (CDC 2015). Using the epidemiological triangle as follows

for
Loiasis:
Agent:
• A parasitic worm known as Loa Loa that causes Loiasis infection
Host:
• A person is usually infected after being bitten by an infected deerfly of the genus Chrysaps.
• These flies are mostly infected after eating blood from an infected person.
Environment:
• Although they have known to migrate deeper into the body Loa Loa lives in subcutaneous tissues throughout the body.
• This parasite can be seen migrating across the bridge of the nose or the subconjunctival tissue of the eye. (Nelson and Williams 2014).
Helpful tips to prevent Loiasis:
• Wearing long sleeve shirts and pants when traveling during the day where these flies live (CDC 2015).
• Using insect repellants (CDC 2015).
• Avoid areas where these flies are mostly found such as muddy, or shaded areas or around wood fires (CDC 2015).