Immuno-Epidemiological Model-Based Prediction of Further Covid-19 Epidemic Outbreaks Due to Immunity Waning

Abstract

We develop a new data-driven immuno-epidemiological model with distributed infectivity, recovery and death rates determined from the epidemiological, clinical and experimental data. Immunity in the population is taken into account through the time-dependent number of vaccinated people with different numbers of doses and through the acquired immunity for recovered individuals. The model is validated with the available data. We show that for the first time from the beginning of pandemic COVID-19 some countries reached collective immunity. However, the epidemic continues because of the emergence of new variant BA.2 with a larger immunity escape or disease transmission rate than the previous BA.1 variant. Large epidemic outbreaks can be expected several months later due to immunity waning. These outbreaks can be restrained by an intensive booster vaccination.

An Epidemic Model with Time-Distributed Recovery and Death Rates

“…Available data for COVID-19 infection do not differentiate between exposed, symptomatic and asymptomatic infected individuals; hence, we can consider them as a single compartment (Ghosh et al. 2022 ).…”

An Epidemic Model with Time Delay Determined by the Disease Duration

“…The model considered in [31] involves distributed recovery and death rates. The model considered in [32] is an extension of the model by incorporating the vaccinated compartment, and the resulting model is an immuno-epidemic model. The delay model, with disease duration delay, considered here is derived from the model proposed in [31] with an appropriate assumption on the recovery and death rate functions.…”

Modelling long-term COVID-19 hospital admission dynamics using empirical immune protection waning data

“…Saad-Roy et alii, 2021 studied different vaccine administration patterns for several scenarios of immunity duration but, their long-term insights were very uncertain because at the time, there was no data on immune protection waning. Finally, Ghosh et alii [2022] used a non-Markovian setting to capture immunity waning but remain on a few months horizon.…”

“…However, their long-term insights were very uncertain because, at the time, there was no data on immune protection waning. Finally, Ghosh et alii [2022] used a non-Markovian setting to capture immunity waning but their scenarios also remained on a few months’ horizon.…”