Malaria is
A) the most common cause of death due to infectious disease worldwide.
B) prevented or treated with chloroquine.
C) controlled by reducing
... [Show More] the population of the mosquito vector.
D) the most common cause of death due to infectious disease worldwide, although it can be controlled by reducing the population of the mosquito vector and prevented or treated with chloroquine.
2) The initial infective stage of the malarial parasite is the
A) sporozoite.
B) merozoite.
C) schizont.
D) plasmodyite.
3) Which of the following human mutations correlates with resistance to plasmodial infections in West Africa?
A) hemoglobin S
B) one particular MHC class I gene
C) one particular set of MHC class II genes
D) hemoglobin S and particular class I and class II genes
4) Which of the following are malaria vaccines currently in development?
A) synthetic peptide vaccines
B) recombinant particle vaccines
C) DNA vaccines
D) synthetic peptide, recombinant particle and DNA vaccines
5) The MOST serious types of fungal infections are
A) subcutaneous infections.
B) mycotoxic infections.
C) systemic mycoses.
D) superficial mycoses.
6) A common mechanism in fungal diseases is
A) endotoxin production.
B) intracellular invasion.
C) hypersensitivity reactions.
D) red blood cell lysis.
7) Many fungi produce ________ that can cause significant disease.
A) cellulases
B) mycotoxins
C) endotoxins
D) chitinases
8) Athlete's foot is an example of a
A) protozoal infection.
B) superficial fungal infection.
C) superficial parasitic infection.
D) hypersensitivity reaction.
9) ALL fungal infections can broadly be termed
A) benign.
B) systemic.
C) superficial.
D) mycoses.
10) The organism causing giardiasis is a
A) gram-negative spirochete.
B) flagellated protozoan.
C) retrovirus.
D) type of yeast.
11) Giardia cysts are able to withstand
A) chemical disinfection.
B) filtration.
C) clarification.
D) chemical disinfection, filtration, and clarification.
12) The microorganism Cryptosporidium parvum is a
A) fungus.
B) bacterium.
C) protozoan.
D) virus.
13) Cryptosporidium parvum oocysts are highly resistant to
A) heat.
B) filtration.
C) desiccation.
D) chlorine.
14) The treatment regimen for people with normal immunity recovering from cryptosporidiosis includes
A) multiple antibiotics.
B) antihelmenthic chemotherapy.
C) multiple antibiotics and careful monitoring of fluid levels.
D) oral rehydration only.
15) An untreated Entamoeba histolytica infection can invade the
A) liver.
B) lungs.
C) brain.
D) liver, lungs, and brain.
16) A common method used in the diagnosis of giardiasis is detection of Giardia
A) cysts in stool.
B) antigens in blood.
C) antigens in stool.
D) cysts or antigens in stool.
17) Naegleria fowleri is a free-living ________ that causes infection by ________.
A) amoeba / entering through the nose and burrowing into the brain
B) fungus / entering the lungs when contaminated soil is disturbed
C) flagellated protist / crossing the intestinal mucosa into the blood
D) protist / entering the vagina in women, the prostate and seminal vesicles of men, or the urethra of both males and females
18) Which of the following is MOST likely to cause an infection in HIV/AIDS patients?
A) Candida albicans
B) Giardia intestinalis
C) Leishmania tropica
D) Schistosoma mansoni
19) What is the infective form of Entamoeba histolytica and Giardia intestinalis?
A) cysts
B) trophozoites
C) merozoites
D) sporozoites
20) Trichomoniasis vaginalis is a sexually transmitted disease that can also survive on moist surfaces and in urine for several hours. As a result, trichomoniasis
A) is difficult to treat.
B) is not a good candidate for eradication.
C) can be spread by contact with contaminated toilet seats, sauna benches, and towels.
D) is more common in males.
21) Roughly half of all adults in the United States are infected with ________ but are asymptomatic.
A) Toxoplasma gondii
B) Trichomoniasis vaginalis
C) Cryptosporidium parvum
D) Cyclospora cayetanensis
22) Which of the following is the MOST common mode of transmission of parasitic infections?
A) direct person-to-person contact
B) contaminated fomites
C) contaminated food or water
D) contaminated needles and syringes
23) Trypanosoma and Leshmania species are transmitted by
A) direct person-to-person contact.
B) insect vectors.
C) contaminated food or water.
D) contaminated needles and syringes.
24) How are trypanosome diseases similar to malaria?
A) They are transmitted by insect vectors.
B) They cause intermittent fevers.
C) They are acute, self-limiting diseases.
D) They are all endemic to Africa.
25) Systemic fungal infections are often transmitted by ________; however, a recent outbreak of fungal disease was traced to ________.
A) accidental inhalation of spores / contaminated injectable pharmaceuticals
B) ingestion of contaminated food / contaminated toilet seats
C) direct contact with skin lesions / sexual contact
D) sexual contact / contaminated toilet seats
26) Which of the following is considered an opportunistic pathogen?
A) Toxoplasma gondii
B) Trichomoniasis vaginalis
C) Candida albicans
D) Plasmodium vivax
27) Giardia intestinalis and Trichomoniasis vaginalis lack ________ and have ________.
A) a flagellum / cilia instead
B) mitochondria / an anaerobic metabolism
C) a cell wall / a rigid cell membrane
D) cysts / sporozoites instead
28) Humans are incidental hosts for ________, thus infected humans CANNOT spread the disease.
A) Toxoplasma gondii
B) Trichomoniasis vaginalis
C) Entamoeba histolytica
D) Plasmodium vivax
29) Hemoflagellates cause tropical diseases such as sleeping sickness and Chagas' disease that are ALL transmitted by
A) contact with fecal contaminated soil.
B) contact with contaminated water.
C) insect vectors.
D) sexual contact.
30) Schistosoma and Plasmodium species both require
A) direct sexual contact for transmission.
B) immunocompromised hosts.
C) transmission by insect vectors.
D) two hosts to complete their life cycle and reproduce.
31) Based on the life cycle of Schistosoma species, which of the following would be MOST effective in controlling schistosomiasis?
A) elimination of stagnate water
B) bed nets
C) proper sewage and water treatment
D) frequent sanitization of shared toilets, showers, and saunas
32) Which of the following filariases can be controlled by thoroughly cooking pork and wild game?
A) elephantiasis
B) river blindness
C) trichinosis
D) schistosomiasis
33) Which of the following filariases are transmitted by insect vectors?
A) elephantiasis
B) river blindness
C) trichinosis
D) elephantiasis and river blindness
True/False Questions
1) The malarial parasite growing within erythrocytes is more resistant than the free parasite to the drug chloroquine.
2) As a malarial infection (Plasmodium falciparum) progresses, gametocytes are formed. The gametocytes unite in the bloodstream before being picked up by the insect vector.
3) The MOST effective malarial control measure is to interrupt the life cycle of the parasite by eliminating the obligate host, the Anopheles mosquito.
4) Plasmodium vivax causes a more serious form of malaria than does P. falciparum.
5) MOST fungi are harmless to humans, although certain superficial infections are quite common.
6) Giardia cysts are found in MOST surface water sources in the United States.
7) Protists that produce spores are especially difficult to kill because they contain cell membranes that are resistant to common disinfecting chemicals.
8) Eukaryotic human parasites are ALL respiratory aerobes.
9) Parasitic helminths only cause very rare tropical diseases.
10) Systemic fungal infections are difficult to treat because active antifungal drugs cause significant host toxicity.
Essay Questions
1) How does insect ecology and the life cycle of Plasmodium impact the epidemiology and pathogenesis of classic malaria?
2) With respect to their life cycles, how are fungal pathogens different than bacterial pathogens?
3) Fifteen high school students visited a local farm in central Wisconsin for a weekend where they enjoyed petting farm animals, riding horses, and campfire meals. With sanitation in mind, only one individual remembered to wash her hands with water pumped from a well after petting the animals before dinner. After two weeks of the girl passing out at random occasions, she was rushed into the emergency room where doctors determined she was severely dehydrated. Explain how it took direct observation of a fecal sample to solve this potential life-threatening disease and how this disease was treated in the otherwise healthy girl. Also mention any necessary precautions the individual should have taken after being diagnosed with the disease.
4) Why do so many eukaryotic pathogens cause highly refractory and long-term chronic infections that are difficult to treat in contrast with prokaryotic pathogens?
5) You and your friends are hiking the Appalachian trail in North Carolina. You run out of water and your friends want to fill up from a beautiful clear stream in the middle of the forest. What precautions should you take before drinking the water and why?
6) Why are systemic fungal infections seen only in a subset of the population, even though most people contact fungi and fungal spores in soil and dust all of the time? Contrast the epidemiology of systemic fungal infections with giardiasis, which infects virtually everyone that comes in contact with the pathogen.
7) How are trypanosome diseases similar to malaria? How are they different than malaria?
8) Use the events in the life cycle of Schistoma mansoni to propose two different strategies to reduce the incidence of snail fever. [Show Less]