Module 9 2.Patho: Describes the four main classes of infectious microorganism: Parasites/Protozoans

Question 1

What kind of relationship do parasitic microorganisms establish?

Answer 1

Parasitic microorganisms establish relationships where the parasite benefits at the expense of the host.

Question 2

What are helminths, and what are some examples of helminths?

Answer 2

Helminths are parasitic worms. Examples include intestinal and tissue nematodes (e.g., hookworm, roundworm), flukes (e.g., liver fluke, lung fluke), and tapeworms.

Question 3

What are protozoa, and what characterizes them?

Answer 3

Protozoa are unicellular microorganisms with a nucleus and cytoplasm. They are eukaryotic in nature.

Question 4

Name some pathogenic protozoa and the diseases they cause.

Answer 4

Pathogenic protozoa include Plasmodium (causing malaria), Entamoeba histolytica (causing amoebic dysentery), Giardia lamblia (causing diarrhea), and Trypanosoma (causing sleeping sickness).

Question 5

What impact do parasites and protozoa have on infections and public health?

Answer 5

Parasites and protozoa are common causes of infections worldwide and have a significant impact on mortality and morbidity, especially in developing countries.

Question 6

Name some protozoa responsible for human diseases.

Answer 6

Protozoa include Entamoeba histolytica (amebiasis), Giardia lamblia (giardiasis), Trichomonas vaginalis (trichomoniasis), Trypanosoma species (Chagas disease and African sleeping sickness), Balantidium coli (balantidiasis), Cryptosporidium species (cryptosporidiosis), Plasmodium species (malaria), and Toxoplasma gondii (toxoplasmosis).

Question 7

What are some examples of helminths that can infect humans?

Answer 7

Helminths encompass flukes (trematodes), like Fasciola hepatica (fasciolosis) and Schistosoma mansoni (schistosomiasis); tapeworms (cestodes), including Taenia solium (pork tapeworm); and roundworms (nematodes), such as Ascaris lumbricoides (ascariasis), Necator americanus (hookworm disease), Trichinella spiralis (trichinosis), Wuchereria bancrofti (filariasis/elephantiasis), Enterobius vermicularis (pinworm infection), and Onchocerca volvulus (onchocerciasis).

Question 8

What disease is caused by Entamoeba histolytica, and what are its symptoms?

Answer 8

Entamoeba histolytica causes amebiasis, leading to symptoms like dysentery and liver abscess.

Question 9

What does Giardia lamblia cause, and what are the typical symptoms?

Answer 9

Giardia lamblia causes giardiasis, which results in diarrhea.

Question 10

Name a protozoan responsible for trichomoniasis and describe its effects.

Answer 10

Trichomonas vaginalis causes trichomoniasis, characterized by inflammation of reproductive organs.

Question 11

What diseases are associated with Trypanosoma species, and which organs are affected?

Answer 11

Trypanosoma species cause Chagas disease and African sleeping sickness, affecting the blood, lymph nodes, and progressing to cardiac and central nervous system (CNS).

Question 12

Name a protozoan causing balantidiasis and its primary site of infection.

Answer 12

Balantidium coli causes balantidiasis, involving the small intestines and colon, leading to diarrhea.

Question 13

What condition is associated with Cryptosporidium species, and where does it primarily infect?

Answer 13

Cryptosporidium species cause cryptosporidiosis, primarily infecting the intestines and causing diarrhea.

Question 14

What is the major disease caused by Plasmodium species, and where do they infect the human body?

Answer 14

Plasmodium species cause malaria, affecting both blood and the liver.

Question 15

What is the disease linked to Toxoplasma gondii, and which organs are involved?

Answer 15

Toxoplasma gondii causes toxoplasmosis, affecting the intestines, eyes, blood, heart, and liver.

Question 16

What is the cause of malaria?

Answer 16

• Plasmodium falciparum, a protozoan parasite.

Question 17

How many cases of malaria were estimated by WHO in 2018, and where were most of them concentrated?

Answer 17

• 228 million cases, with 94% in Africa.

Question 18

Which vectors transmit protozoan parasites, and what diseases do they cause?

Answer 18

Tsetse flies transmit Trypanosoma cruzi (Chagas disease) and Trypanosoma brucei (sleeping sickness).

• Sand fleas transmit leishmaniasis.

Question 19

How can protozoal parasites be transmitted through ingestion?

Answer 19

• Contaminated water and food, e.g., Entamoeba histolytica and Giardia lamblia.

Question 20

How is Plasmodium, the parasite that causes malaria, primarily transmitted?

Answer 20

• Through the bite of an infected female Anopheles mosquito.

Question 21

Where does the Plasmodium parasite grow within the mosquito?

Answer 21

• In the mosquito’s salivary gland.

Question 22

What is the basis for microorganism attachment to cells in the body?

Answer 22

The presence of microorganisms in the bloodstream or gastrointestinal tract.

Question 23

What are the surface proteins of microorganisms in the bloodstream used for?

Answer 23

To attach to various cell receptors, including macrophages, red blood cells, and organ cells.

Question 24

How does Plasmodium multiply, and what is the consequence of this multiplication?

Answer 24

Plasmodium multiplies within erythrocytes, leading to periodic lysis (every 48 to 72 hours) and subsequent anemia.

Question 25

What happens when erythrocytes undergo lysis during a Plasmodium infection?

Answer 25

It induces the release of cytokines such as TNF-α, IFN-γ, and IL-1, leading to symptoms like fever, chills, sweating, headache, muscle pains, and vomiting.

Question 26

What are some severe symptoms that can result from Plasmodium infection?

Answer 26

Severe symptoms may include anemia, pulmonary edema, and other complications, which can potentially be fatal.

Question 27

How can Plasmodium infection lead to neurological complications?

Answer 27

Infected red blood cells adhering to the endothelium in the brain’s capillaries can cause neurological complications.