Protozoan Pathogens Lab

Protozoan Pathogens Lab Report

Introduction to Eukaryotic Pathogens

1. Review the differences between prokaryotes (bacteria) and eukaryotes.  Which category do humans fall into?
2. Do you think it is easier to design a drug to treat a bacterial pathogen or a eukaryotic pathogen. Explain your answer.

Introduction to Protozoa

1. What is the structure that some bacteria make that is analogous to the cyst that some protozoa make?  Explain the similarities.
2. Which mode of locomotion listed above are also found in bacteria?  Which are unique to eukaryotes?
3. What are some other similarities between protozoa and bacteria?  What is the major difference?

Flagellates

Giardia:

1. What is the mode of transmission?  The reservoir?
2. Once inside the host, the cyst enters the stomach where the acidic environment leads to excystment.  Why is this a necessary step in the life of the parasite?  In other words, explain why the protozoa needs to be in the trophozoite form.

Unknown #1:

1. On the image below label the structures used for movement (what are they called and where are they?) as well as the dark purple oval (what is it called) in the center.

1. Determine the size of the organism if approximately 8 fit across the field of view at 1000x total magnification.  Use the table found on the Canvas page.
2. What is the full name (Genus species) of the protozoa?  Hint:  For the rest of the lab report, be sure to use the proper scientific format for any scientific names (Upper case letter for genus, lower case for species, the name should be in italics)!
3. What is the prevalence (%) of this pathogen in the United States?   What piece of information did you have to look up to calculate this?
4. Even though most people are asymptomatic, there are some complications/issues if these infections go unnoticed.  Explain what these are and who they affect.
5. If you had this infection, what would the treatment be?  This treatment has also been shown to be effective against some bacteria.  Explain, without any more information,  why that is a surprising finding based on what you know about this unknown and bacteria.

Ciliates

1. The cilia are more visible and active in the trophozoite form vs the cyst.  Given the function of the trophozoite and the cyst, this makes lots of sense.  Why?
2. This organism’s cilia are used for movement and attachment to host cells.  Why would cilia be considered a virulence factor for these protozoa?
3. Explain why a trophozoite would encyst and why a cyst would excyst.
4. What mode of transmission is used by this pathogen?
5. Discuss the main mode of prevention for this disease and how might the World Health Organization and other agencies aid in this preventative measure?

Amoeboid

1. What is the morbidity rate of the disease?
2. What do you notice about the shape of the cyst compared to the trophozoite?  Look at other cysts as well.  Do they have the same general shape?  Explain.
3. Discuss why cysts are more difficult to kill.
4. Why would antibody tests be more definitive than looking at a stool sample?  Remember that you’ve learned about antibody tests for SARS-CoV2.
5. In a live trophozoite, explain what a video of the movement of the organism would look like.  How is that different from the flagellates and ciliates?

Apicomplexans

Plasmodium

1. What percentage of people that have malaria live in Africa?
2. How many total cases were reported worldwide?
3. What do you think would happen if that many deaths were caused by a disease in the U.S. or Western European country?  How is that different from what happens in Africa?
4. Mosquito nets are one of the most effective interventions against malaria.  Explain how mosquito nets can help prevent the spread of this disease.

Unknown #2

1. What is the unknown apicomplexan pathogen?
2. What types of undercooked meat can carry this organism?
3. Explain how the protozoa causes harm during pregnancy.
4. What household chore should pregnant women not do to prevent catching this parasite?
5. What do Plasmodium and this unknown apicomplexan have in common?  How are they different?

Neglected Tropical Diseases

1. Who is neglecting these diseases?
2. Explain the connection between the two cycles shown above.  How is poverty linked to mental illness in this case?  Can you think of other examples of this connection?

NTDs caused by Protozoan Pathogens

Leishmania

1. What is the mode of transmission?
2. What group of protozoa does this pathogen belong in.
3. What is the dark oval in the center of each one?

1. If the picture shown above was taken from an infected human’s blood, using the image of the life cycle determine what would likely happen next inside the person?

• Where else have you heard about this process taking place? What does this tell you about whether it is innate or adaptive immunity?  Explain how you know.

1. What do you think highly endemic means?
2. What is the incidence (%) in a year?  (Remember, the world’s population is 7.8 billion.)
3. Do a bit of research on WHO or CDC website to figure out some of the control measures being put into place to help slow the spread of this disease.  What is the current trend as far as number of worldwide infections compared to a decade or so ago?

Unknown #3

1. On the picture below, label the structures used for movement.  Which of the four groups of protozoa does it fall into?

1. What is the Genus?
2. Fill in this table for both species

1. Explain why these illnesses are included in the category of neglected diseases.