Infection Diseases / Infections

How can human microbial virulence be estimated?

• No more than a dozen known microbes can kill more than 10% of infected individuals, even without medical prevention and treatment.


• Fewer than 100 microbes can kill more than 1% of infected individuals.


• Most of the remaining 3,000 known pathogens are less virulent and cause life-threatening disease in <1% of infected individuals
  The observed infection-fatality ratio is probably the best estimate of human microbial virulence (1)

Although data on infection fatality are lacking, it is generally believed that the outcome of an infection is determined primarily by qualitative (pathogenicity) and quantitative (inoculum) microbial factors.
Abel & Casanova 2024 Immunity 57(7): 1457-1465

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