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Q45 - Cross-Immunity and Persistence Explain Smallpox's Eradication over Cholera's

Theoretical B Real exam question - full text reproduced under IBO's CC BY-NC-SA 4.0 license
Immune Physiology

Edward Jenner (1749-1823), the inventor of immunology, pioneered modern vaccination. Jenner noticed milkmaids exposed to cowpox did not catch smallpox. Jenner injected pus from a cowpox infection (top), into a boy, who became mildly ill. Jenner later injected the boy with pus from a smallpox victim (bottom), and the boy did not become ill (1). Smallpox was usually spread through the respiratory tract, was highly contagious, and quite deadly, but, due to vaccination, is now the only human pathogen to have been driven extinct.

Figure 1 for Q45: Cross-Immunity and Persistence Explain Smallpox’s Eradication over Cholera’s

Using the information and data, determine which of the statements are true or which are false.

A. Smallpox and Cowpox share some amino-acid sequences on their surface.
B. People often contracted smallpox more than once.
C. Snow ended the Cholera outbreak by removing the handle from the Warwick Street water pump.
D. Smallpox remains viable outside of the host for longer than Cholera.
E. Smallpox lingers in isolated communities longer than Cholera.
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Question reproduced from IBO 2017, Theoretical Exam B, licensed under CC BY-NC-SA 4.0 - attributed to the International Biology Olympiad. Open the full exam PDF · Official answer key & worked solutions