A 71-year-old man with chronic obstructive pulmonary disease (COPD) is hospitalized due to shortness of breath and wheezing. The patient is treated with bronchodilators and systemic corticosteroids for acute COPD exacerbation. His symptoms improve over the next 2 days. Before being discharged, an intramuscular vaccine containing inactivated viral components, which he normally receives annually, is administered. Several weeks later, the patient comes in close contact with an individual infected with the same virus contained in the vaccine. Which of the following is most likely to occur in this patient as a result of the vaccination?

Question

A 71-year-old man with chronic obstructive pulmonary disease (COPD) is hospitalized due to shortness of breath and wheezing.  The patient is treated with bronchodilators and systemic corticosteroids for acute COPD exacerbation.  His symptoms improve over the next 2 days.  Before being discharged, an intramuscular vaccine containing inactivated viral components, which he normally receives annually, is administered.  Several weeks later, the patient comes in close contact with an individual infected with the same virus contained in the vaccine.  Which of the following is most likely to occur in this patient as a result of the vaccination?

Quizplus · Accepted Answer

11ec160b_37d3_eecc_9249_49043737750e_MD0001_00 Influenza vaccination is administered either by injection (inactivated [killed] vaccine) or nasal spray (live attenuated vaccine). Each seasonal influenza vaccine contains antigens (or attenuated virions) from 3 or 4 influenza A and B virus strains. Antigens from multiple influenza types are included in the vaccine because antibodies against 1 strain confer limited or no protection against the others. Annual vaccination is recommended due to waning effectiveness over time and because circulating strains of influenza change from year to year. All individuals age >6 months should be immunized, especially health care workers and those at risk of serious complications such as the elderly, patients with chronic illness (eg, chronic obstructive pulmonary disease), and immunocompromised individuals. Inactivated versions of the influenza vaccine stimulate the formation of neutralizing antibodies against the hemagglutinin antigen of included strains. Subsequent exposure to a strain of influenza included in the vaccine will not result in infection because the antibodies bind to hemagglutinin, thereby preventing hemagglutinin from attaching to the sialic acid receptor on host respiratory epithelial cells (preventing viral entry). (Choice A) Because inactivated viral vaccines do not infect host cells, they are not processed by the MHC class I pathway and do not stimulate a potent CD8⁺ T-cell response. In contrast, live attenuated influenza vaccines replicate in nasopharyngeal cells and are displayed on MHC class I molecules, thereby generating a strong cytotoxic T-cell response that results in the destruction of the infected cell. (Choices B and E) Protective antibodies against influenza primarily target the surface glycoproteins and impair viral entry. Immunization does not typically affect viral genomic replication or assembly, which occurs in the interior of the cell and cannot be targeted easily by an antibody response. (Choice C) Neuraminidase cleaves the terminal sialic acid residues on glycoconjugate receptors, which releases influenza virions from infected cells. Oseltamivir is a sialic acid analogue that competitively inhibits influenza neuraminidase, which prevents release of viral progeny. Educational objective: Inactivated (killed or component) viral vaccines primarily generate a humoral immune response against extracellular viral antigens, preventing viral entry into the cell. In contrast, live attenuated viral vaccines can generate a strong cell-mediated immune response that can kill virally-infected cells, in addition to providing humoral immunity.

A 71-Year-Old Man with Chronic Obstructive Pulmonary Disease (COPD) Is