Before the smallpox vaccine, what was the fatality rate of smallpox?

Before the smallpox vaccine, what was the fatality rate of smallpox?

• A. 30-60%
• B. 5-10%
• C. 70-90%
• D. 10-20%

Answer: (A)

Smallpox was extremely deadly before vaccination. Among those infected, about one in three died on average, but the exact fatality rate varied by outbreak and form of the disease, with some waves killing up to about 60% of cases. That makes the range of 30-60% the best fit for pre-vaccine mortality. Figures like 5-10% or 10-20% would seriously underestimate how deadly the disease could be, while 70-90% would overstate it beyond what most outbreaks produced, even in the more severe forms.

Smallpox was extremely deadly before vaccination. Among those infected, about one in three died on average, but the exact fatality rate varied by outbreak and form of the disease, with some waves killing up to about 60% of cases. That makes the range of 30-60% the best fit for pre-vaccine mortality. Figures like 5-10% or 10-20% would seriously underestimate how deadly the disease could be, while 70-90% would overstate it beyond what most outbreaks produced, even in the more severe forms.