Interventions to mitigate the spread of infectious diseases, while succeeding in their goal, have economic and social costs associated with them. These limit the duration and intensity of the interventions.
Pratyush K. Kollepara, Rebecca H. Chisholm, Istvan Z. Kiss, Joel C. Miller


This study investigates a class of interventions which reduce the reproduction number and find the optimal strength of the intervention which minimises the attack rate of an immunity inducing infection.

The intervention works by eliminating the overshoot part of an epidemic, and avoids a second-wave of infections.


This work has examined a strategy of optimal interventions which uses the epidemic to cause just enough infections to induce herd immunity, eliminate the overshoot, and prevent future introductions from becoming epidemics. In addition to minimising the attack rate, this intervention would also slow down the growth of the epidemic and reduce the peak, which allows time to develop treatments and increase healthcare capacity.

View full modelling work
First published: Feb 23, 2023
Infectious Disease Modelling La Trobe
[COVID-19 Modelling Aotearoa](, is a cross-organisation and transdisciplinary group of academic researchers and scientists that were brought together by Te Pūnaha Matatini to help Aotearoa New Zealand face the COVID-19 pandemic. Our work is underpinned by Te Tiriti o Waitangi, fast and committed peer review, and ethics. These parameters ensure that the modelling developed by our broad team is uniquely equipped to provide scientifically robust results which are fit for Aotearoa New Zealand and support our decision-making.