Waec Model Questions Vol1 2025 Biology Question 20
Practice objective / multiple choice question 20 from the 2025 Waec Model Questions Vol1 Biology examination.
In a closed community of 10 000 individuals, an infectious disease follows the SIR model with a transmission rate β = 0.3 day⁻¹ and a recovery rate γ = 0.1 day⁻¹. (a) Compute the basic reproduction number R₀. (b) Using the formula for the herd‑immunity threshold H = 1 - 1/R₀, determine the proportion of the population that must be immune to stop transmission. (c) If a vaccine available for this disease has an efficacy of 85 %, what minimum vaccination coverage (as a percentage of the total population) is required to achieve herd immunity? Present your answer to one decimal place.
Answer Options
About This Question
This is Waec Model Questions Vol1 2025 Biology Question 20. It is one of the objective questions from the 2025 Waec Model Questions Vol1 Biology examination.
Difficulty level: Hard .
Master the Exam!
You've seen a preview, but there are thousands more questions plus AI tutor to break down complex solutions.