Infection Fatality Rate (IFR)

The Infection Fatality Rate (IFR) is different from a Case Fatality Rate. The IFR is determined from all of those who contracted an infection, including those who were asymptomatic and did not develop clinical symptoms.


On the other hand, the Case Fatality Rate measures how many fatalities occur after clinical symptoms are observed. In most cases the media reports on Case Fatality Rates which is why most statistics seen are significantly higher.

Papers and articles on the IFR:

23 December 2021 - pre-print

Meta-Research Innovation Center at Stanford (Stanford University)

Infection Fatality Rates
  0-19  years 0.0013%,
20-29 years 0.0088%,
30-39 years 0.021%,
40-49 years 0.042%,
50-59 years 0.14%,
60-69 years 0.65%

The median IFR in community-dwelling elderly and elderly overall was 2.9% (range 0.2%-6.9%) and 4.9% (range 0.2%-16.8%) without accounting for seroreversion (2.4% and 4.0%, respectively, accounting for 5% monthly seroreversion)

European Journal of Clinical Investigation:
Reconciling estimates of global spread and infection fatality rates of COVID-19: An overview of systematic evaluations
John Ioanndis

Infection Fatality Rate (average) = 0.15%

March 2021

March 2021

Centers for Disease Control

No author attributed

Infection Fatality Rates

 0 - 17yo    = 0.002  %

18 - 49yo   = 0.05    %

50- 64yo   = 0.6      %

     - 65+     = 9.0      %

May 2020
World Health Organisation:
Infection fatality rate of Covid-19 inferred from seroprevalence data

Original Link:
Download pdf
John P A Ioanndis

IFR Corrected median overall                            = 0.23%
IFR Corrected median for under 70 years        = 0.05%

Dec 2020

JAMA Network:

(multiply numbers by 1.5 to get an annualised figure)

Deaths per million (JAMA).png