Week 6 Mastering

Based on Claire's medical history and the Gram stain results, which is most likely causative organism?

N. meningitdis

Sort the terms below by whether they apply to the mosquito host, human host, or both.

MOSQUITO definitive host sexual reproduction zygote HUMAN trophozoite intermediate host merozoite BOTH gametocyte sporozoite

What disease does Paul suspect Ron might have contracted?

Rocky Mountain spotted fever

Select all disease that include recurrent periods of fever among their symptoms

Brucellosis Relapsing fever Malaria Leishmaniasis Babesiosis

A woman just found out that she is pregnant. As a first-time mother-to-be and student in microbiology, she is worried about all the different microbes that could potentially harm her unborn child. What is the term used to describe the transmission of microbes from mother to fetus via the placenta or during delivery?

Vertical transmission

Which of the following statements about meningitis is TRUE?

Viral meningitis, while less severe than bacterial meningitis, is more common in occurence.

Which of the following climate change scenarios has allowed for this increase in vector habitat?

Warmer temperatures in northern regions with increased rainfall

Select the answer that most impacts the type of antimalarial drug you will administer

Where the parasite was originally important from, since it is not endemic

Which other recommendations will any pregnant mother be given in order to prevent exposure to pathogens that can be vertically transmitted? Select all statements that are correct.

Avoid cleaning cat litter boxes to prevent exposure to T. gondii

Keep in mind the principles behind indirect fluorescent-antibody testing, which of the following characteristics contributes to its choice as the gold standard?

-Indirect FA is rapid, sensitive, and specific. -Indirect FA is more sensitive than direct immunifluorescent testing. -Indirect FA uses an antibody that reacts with any human antibody. -Indirect FA will detect R. rickettsii-specific antibodies present in the patient's serum.

Apply your knowledge of RMSF to choose the most likely reasons behind this recommendation.

-Most tests that can definitevely identify R. rickettsii are not effective early in infection -The symptoms of RMSF are similar to those of several other infections, making definitive diagnosis difficult. -Without prompt treatment, RMSF can have a mortality rate as high as 20%. -A deelay in treatment can lead to complications that include respiratory, cardiac and renal failure.

What is the most liekly sequence of events involved in the pathogenesis of meningococcal meningitis?

-N. meningitidis enters & attaches to the nasopharyngeal epithelium - The organism passages through the mucosa and enters the blood -N. meningitidis crosses the blood-brain barrier -A massive influx of polymorphonuclear cells leads to increased pressure in the brain -Hearing, vision, motor skills impaired

RMSF results from the interactions that occur between R. rickettsii pathogen and the host. The infection results from a coordinated series of events that ultimately result in disease.

-Tick bites transmit R. rickettsii into bloodstream. -R. ricketsii travels throughout the body via the blood & lymph systems -R. rickettsii invades endothelial cells of blood vessels. - R. rickettsii multiples within host cells - Blood begins to escape from a vessels as a result of increased vascular permeability -Symptoms, such as a macular rash, develop.

Match each disease with its vector organism or mode of transmission. Each correct answer is used only once.

1. Brucellosis: Unpasteurized dairy products 2. Relapsing fever: Soft ticks 3. Malaria: Anopheles mosquitoes 4. Leishmaniasis: Sandfly 5. Babesiosis: Ixodes ticks

A patient comes in with a possible Chikungunya infection. Rank the following in order.

1. Uninfected mosquito feeds on an infected person 2. Replication of the virus inside the vector 3. Infected mosquito feeds on uninfected person 4. Patient has fever, headaches, and joint pain 5. Treatment with supportive therapy

What is the most common accurate method to confirm a diagnosis of malaria?

A blood smear

What diagnostic test would be most useful at this stage of Dr. Peterson's diagnosis?

A lumbar puncture to obtain a sample of CSF

How did John most likely get infected?

A mosquito bite

How does this help prevent further spread of infection?

Additional bites would increase the chances of an uninfected vector acquiring the virus

Why were these protective measures not enought to keep him from being infected?

Aedes mosquitos prefer to live inside buildings, are more resistant to bug spray, and feed during the day.

Rickettsia rickettsii is a gram-negative, obligate intracellular pathogen. Which of the following statements about the R. rickettsii life cycle is FALSE?

After entering a host, R. rickettsii multiplies to levels high enough to successfully invade cells and establish an infection.

Based upon your patient's history, which vector organism could he most easily been exposed to?

Anopheles mosquitoes

A pregnant woman found a large variety of microbes that can be vertically transmitted. She is making a list for her doctor to assess her risk of becoming infected with any of the,=m. Match the infectious agents with their respective classification.

BACTERIAL T. pallidium Elizabethkinga L. monocytogenes VIRAL HSV-2 CMV Neither T. gondii

Why would conjugation to a protein carrier improve the efficacy of a polysaccharide vaccine?

In contrast to polysaccharide vaccines, protein-conjugated vaccines elicit a strong T-cell dependent response

What could jaundice signify for your patient?

Liver damage Anemia

You know that P. falciparum malaria in Haiti is frequently chloroquine-resistant. Thus, what drug will you use to treat your patient.

Malarone Oral quinine & tetracycline

In microbiology class, a pregnant student learned about the TORCH test. This panel of tests was originially developed to screen mothers for antibodies to microbes that can harm their fetuses. Which of the following microbes and diseases are included in the TORCH test?

Measles Rubella Herpes Chickenpox

What is the likely cause for the drop in glucose levels?

N. meningitidis uses the glucose as a source of energy to fuel its growth

Select all that apply. Indicate "Yes" with a red checkmark, and "No" with a blue checkmark.

No No No No Yes (drug-related exposure) No No No No

Given the speed and severity of your patient's symptoms, which species of Plasmodium do you think is causing your patient's malaria?

P. falciparum

What are the two circular dark purple structures that appear in the middle of the central red blood cell?

P. trophozoite

Which of the following is a characteristic of biological transmission from Dermacentor to human host?

R. rickettsii is transmitted to the human host during a bite, when tick saliva enters the wound.

Claire's symptoms are characteristic of many different infections. Why does Dr. Peterson suspect that Claire may have meningitis?

The closed, mixed environment of the college dorm allows for infection of susceptible students. There have been documented cases of meningitis in Claire's dorm

Why is bacterial meningitis considered more life threatening than viral meningitis?

The immune response generated against bacteria leads to a massive influx of immune cells in the meninges; this response is much less extreme in viral meningitis.

What is a likely result of the elevated WBC level in Claire's CSF?

There will be an extreme inflammatory response which will eventually lead to shock and ultimately to Claire's death

After returning from a family trip to Brazil, suffering from a fever and experiencing some minor joint and muscle pain and conjunctivitis, a pregnant woman has an appointment with her doctor. What will the doctor likely be testing her for after learning about her trip?

Zika virus disease

What part of the United States is endemic for RMSF?

the Appalachian region