On a single day snapshot, a city of 200,000 residents reports 1,000 people currently infected with disease X, including 100 new diagnoses that week and 900 preexisting cases. What is the point prevalence proportion (%) on that day?

• A. 0.05% prevalence (1,000 ÷ 2,000,000 × 100%).
• B. 0.5% prevalence (1,000 ÷ 200,000 × 100%).
• C. 0.05% incidence, because prevalence and incidence are always numerically identical at a snapshot.
• D. 5% prevalence (1,000 ÷ 20,000 × 100%).

Answer: (B)