Why Didn’t They Teach This in Med School?
A series on new (and not-so-new) medical terms and diagnoses that most of us (probably) missed in training
How would you rate your understanding of epidemiologic terms?
Reading about COVID-19, you may have encountered the four parameters mentioned in this question. Which one indicates the risk unit defined as one-in-a-million chance of death?
A. Micromort
B. Microprobability
C. R0
D. Rt
Read on to see the answer!
Answer: A. Micromort
Micromorts are used to measure the risk inherent in various daily activities. A microprobability is a one-in-a million chance of any given event; a micromort is the microprobability of death.
For an average American, the risk of dying of unnatural causes is one in a million per day, or one minimort (1). The risk of dying under general anesthesia is five per million, or five minimorts. For COVID-19, the exact micromort value cannot yet be calculated – and it depends on many variables.
R0, a measure of microbial spread, is defined as the expected number of secondary infectious cases produced by a primary infectious case. To control an epidemic, R0 must be brought below 1. Rt (the effective reproduction number) determines the potential for epidemic spread at a specific time t under the control measures in place. Social interaction during the SARS-CoV-2 pandemic has dramatically reduced Rt in many countries (2).
- DC Roberts (2020). Available at: nyti.ms/3heEiEz.
- TV Inglesby, JAMA, [Epub ahead of print] (2020). PMID: 32356869.
Professor Emeritus of Pathology at the University of Kansas, Kansas City, USA.
