Smallpox eradication was successful due to all of the following reasons except: (A) Subclinical cases did not transmit the disease, (B) A highly effective vaccine was available, (C) Cross-resistance existed with animal pox, (D) Infection provided lifelong immunity
Answer is C. Epidemiological Reasons/Basis For Smallpox Eradication:
• No known animal reservoir
• No long term carrier state
• Infection provides lifelong immunity
• Case detection simple due to characteristic rash
• Subclinical cases did not transmit the disease
• A highly effective vaccine was available
• International cooperation