Viral Break-In
A negative-sense RNA virus enters a cell, but its packaged polymerase is inactive. What essential process cannot begin?
What is transcription?
Which animal is the established natural reservoir for Marburg virus?
What is Egyptian fruit bats.
Which immune cells are important early targets of Ebola infection and normally help coordinate immune responses?
What are marcophages?
A patient has fever, cough, a runny nose, and red eyes. What classic viral illness should be considered, particularly if a descending rash follows?
What is measles?
What type of isolation is required for suspected measles or infectious pulmonary TB?
What are airborn precautions
Which bacterium discussed has a waxy, mycolic acid-rich cell envelope?
What is Mycobacterium tuberculosis.
A Nipah virus can recognize its host-cell receptor but cannot merge its envelope with the cell membrane. Which viral protein is likely defective?
What is the F (fusion) protein?
A person contracts Nipah after drinking sap contaminated by fruit bats. Is this direct zoonotic spillover or transmission through an intermediate host?
What is direct zoonotic spillover?
A patient recovers from measles but becomes unusually susceptible to previously encountered infections. What phenomenon explains this?
What is immune amnesia?
What laboratory technique detects viral genetic material and is used in diagnosing acute Nipah infection?
What is RT-PCR?
Why does receiving two recommended doses of MMR reduce a person's risk of measles?
What is vaccination establishes protective adaptive immune memory.
An infected macrophage contains TB bacteria inside a phagosome. What normal cellular event do the bacteria interfere with to survive?
What is phagosome maturation and fusion with lysosomes.
A measles variant loses its ability to bind CD150. Which part of its infection process would be particularly disrupted?
What is Infection of susceptible immune cells and spreading
In a livestock-associated Nipah outbreak, pigs become infected and spread the virus to many farm workers. What epidemiological role do pigs play?
What is amplifying host?
A Nipah patient develops encephalitis alongside inflammation of small cerebral blood vessels. Name two tissues or cell types involved in this disease process.
What is vascular endothelial cells and nervouse system cells?
A person has persistent cough, night sweats, weight loss, and abnormal chest imaging. Another has a positive IGRA but no symptoms. Which person needs evaluation for potentially infectious pulmonary TB, and why?
Who is The symptomatic person; the findings raise concern for active pulmonary disease, whereas latent infection is not contagious
A community has high overall MMR coverage but a school with many unvaccinated students. Why might an outbreak still occur at that school?
What is susceptible people are clustered together, creating opportunities for sustained transmission.
A TB granuloma contains bacteria for years without eliminating them. What could happen if immune containment weakens?
What is the infection may reactivate and progress to active TB disease.
Two antivirals target Ebola. Drug A blocks GP-mediated entry; Drug B inhibits viral RNA synthesis. Which drug acts earlier in the infection cycle?
What is Drug A
A Marburg patient becomes ill after a wildlife exposure. Several funeral attendees later develop symptoms. What change in transmission route should investigators consider?
What is an initial zoonotic infection followed by human-to-human transmission through contact with infectious bodily fluids.
A patient with severe Ebola has extensive gastrointestinal fluid loss and increased vascular permeability. Explain why blood pressure may fall.
What is loss of circulating fluid and vascular leakage reduce effective blood volume and tissue perfusion.
A patient has a positive TB IGRA but no symptoms. What important distinction has the test not established?
What is whether the patient has letent TB infection or active TB disease?
A hospital receives a patient with suspected pulmonary TB. Why is improving room ventilation more directly useful for transmission control than disinfecting desks alone?
What is TB spreads primarily through airborne particles, so ventilation reduces their concentration in shared air.
A patient with severe Nipah has seizures and respiratory failure. Without a licensed specific treatment, what two immediate clinical priorities are important?
What is manage seizure and provide respiratory support?