Complexity of the Basic Reproduction Number (R0).

Paul L Delamater,Erica J Street,Timothy F Leslie,Y Tony Yang,Kathryn H Jacobsen

doi:10.3201/eid2501.171901

Abstract

The basic reproduction number (R0), also called the basic reproduction ratio or rate or the basic reproductive rate, is an epidemiologic metric used to describe the contagiousness or transmissibility of infectious agents. R0 is affected by numerous biological, sociobehavioral, and environmental factors that govern pathogen transmission and, therefore, is usually estimated with various types of complex mathematical models, which make R0 easily misrepresented, misinterpreted, and misapplied. R0 is not a biological constant for a pathogen, a rate over time, or a measure of disease severity, and R0 cannot be modified through vaccination campaigns. R0 is rarely measured directly, and modeled R0 values are dependent on model structures and assumptions. Some R0 values reported in the scientific literature are likely obsolete. R0 must be estimated, reported, and applied with great caution because this basic metric is far from simple.

Highlights

The basic reproduction number (R0), called the basic reproduction ratio or rate or the basic reproductive rate, is an epidemiologic metric used to describe the contagiousness or transmissibility of infectious agents
The potential size of an outbreak or epidemic often is based on the magnitude of the R0 value for that event [10], and R0 can be used to estimate the proportion of the population that must be vaccinated to eliminate an infection from that population [14,15]
We address misconceptions about R0 that have proliferated as this metric has become more frequently used outside of the realm of mathematical biology and theoretic epidemiology, and we recommend that R0 be applied and discussed with caution

Summary

Introduction

The basic reproduction number (R0), called the basic reproduction ratio or rate or the basic reproductive rate, is an epidemiologic metric used to describe the contagiousness or transmissibility of infectious agents. Variations in R0 For any given infectious agent, the scientific literature might present numerous different R0 values.

Results

Conclusion