Minimising the use of costly control measures in an epidemic elimination strategy: a simple mathematical model

Type of content
Journal Article
Thesis discipline
Degree name
Publisher
Elsevier BV
Journal Title
Journal ISSN
Volume Title
Language
en
Date
2022
Authors
Plank, Michael
Abstract

Countries such as New Zealand, Australia and Taiwan responded to the Covid-19 pandemic with an elimination strategy. This involves a combination of strict border controls with a rapid and effective response to eliminate border-related reintroductions. An important question for decision makers is, when there is a new re-introduction, what is the right threshold at which to implement strict control measures designed to reduce the effective reproduction number below 1. Since it is likely that there will be multiple re-introductions, responding at too low a threshold may mean repeatedly implementing controls unnecessarily for outbreaks that would self-eliminate even without control measures. On the other hand, waiting for too high a threshold to be reached creates a risk that controls will be needed for a longer period of time, or may completely fail to contain the outbreak. Here, we use a highly idealised branching process model of small border-related outbreaks to address this question. We identify important factors that affect the choice of threshold in order to minimise the expect time period for which control measures are in force. We find that the optimal threshold for introducing controls decreases with the effective reproduction number, and increases with overdispersion of the offspring distribution and with the effectiveness of control measures. Our results are not intended as a quantitative decision-making algorithm. However, they may help decision makers understand when a wait-and-see approach is likely to be preferable over an immediate response.

Description
Citation
Plank MJ (2022). Minimising the use of costly control measures in an epidemic elimination strategy: a simple mathematical model. Mathematical Biosciences. 108885-108885.
Keywords
branching process, epidemiological modelling, infectious disease modelling, public health
Ngā upoko tukutuku/Māori subject headings
ANZSRC fields of research
01 Mathematical Sciences
06 Biological Sciences
Fields of Research::42 - Health sciences::4202 - Epidemiology::420205 - Epidemiological modelling
Fields of Research::31 - Biological sciences::3107 - Microbiology
Fields of Research::49 - Mathematical sciences
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