Which population is 3x more likely to develop pneumococcal bacteremia?

• A. Pregnant women
• B. Young children
• C. Older adults
• D. Healthy adults

Answer: (C)

Older adults are more likely to develop pneumococcal bacteremia because aging brings immune system changes and more chronic illnesses that weaken defenses against encapsulated bacteria like Streptococcus pneumoniae. This combination increases the likelihood that a pneumococcal infection becomes invasive and enters the bloodstream, resulting in bacteremia. Epidemiologically, the risk of invasive pneumococcal disease is highest in the elderly compared with healthy adults, roughly three times higher, which is why this population is the best answer.

Pregnant women can have altered immunity, but they do not experience this same threefold rise in bacteremia risk, and healthy adults have the lowest baseline risk among the options. Young children have higher overall risk for pneumococcal disease, but the specific threefold increase relative to healthy adults is characteristic of older adults.