Virology USMLE Step 1 Practice Question
A 53-year-old engineer with diabetes mellitus comes to the employee health center for an annual examination. She has no complaints at this time. A review of her chart reveals that she is due for a few vaccinations, including the influenza A vaccine. She questions the physician about the necessity of the vaccine because she just received one a year ago. Which of the following statements about the influenza A virus best explains why last year's vaccine may be ineffective?
Answer choices
- AIt has a heavy polysaccharide coat.
- BIt kills lymphocytes.
- CIt immunosuppresses the patient.
- DIt resists inactivation by complement.
- EIt undergoes genetic reassortment.Correct answer
- FIt integrates its genome into host chromosomes.
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