Impact of Infective Immigrants on COVID-19 Dynamics

Abstract

The COVID-19 epidemic is an unprecedented and major social and economic challenge worldwide due to the various restrictions. Inflow of infective immigrants have not been given prominence in several mathematical and epidemiological models. To investigate the impact of imported infection on the number of deaths, cumulative infected and cumulative asymptomatic, we formulate a mathematical model with infective immigrants and considering vaccination. The basic reproduction number of the special case of the model without immigration of infective people is derived. We varied two key factors that affect the transmission of COVID-19, namely the immigration and vaccination rates. In addition, we considered two different SARS-CoV-2 transmissibilities in order to account for new more contagious variants such as Omicron. Numerical simulations using initial conditions approximating the situation in the US when the vaccination program was starting show that increasing the vaccination rate significantly improves the outcomes regarding the number of deaths, cumulative infected and cumulative asymptomatic. Other factors are the natural recovery rates of infected and asymptomatic individuals, the waning rate of the vaccine and the vaccination rate. When the immigration rate is increased significantly, the number of deaths, cumulative infected and cumulative asymptomatic increase. Consequently, accounting for the level of inflow of infective immigrants may help health policy/decision-makers to formulate policies for public health prevention programs, especially with respect to the implementation of the stringent preventive lock down measure.

Mathematical Modeling to Study Optimal Allocation of Vaccines against COVID-19 Using an Age-Structured Population

“…In this work, we were interested in studying different vaccination strategies in regard to which groups to vaccinate first. Different mathematical models that include vaccinated people and take into account the efficacy of the vaccine have been developed [64][65][66][67]. For instance, in [65] the authors proposed a stochastic epidemic model, and they found that white noise can result in the extinction of the disease even with a smaller reproduction number.…”

Effective screening strategies for safe opening of universities under Omicron and Delta variants of COVID-19

“…[33] develops a compartmental model to investigate the impact of vaccination coverage on different outcome metrics under the Omicron variant and a less transmissible variant. Importantly, neither work [31,32,33] models and studies screening strategies, which is the main focus of our paper. Specifically, we contribute to this stream of literature by building an extended compartmental model to study routine screening strategies, which may be customized based on the vaccination status and/or the demographics of campus residents.…”

“…The academic literature related to Omicron is still quite limited: [31] develops a compartmental model to predict various outcome metrics related to the Omicron variant under different transmission and severity scenarios, while [32] develops a compartmental model that considers vaccination (including boosters), waning immunity from the vaccine, and different COVID-19 variants (including Omicron), in order to estimate the reduction in transmission rates, and its effect on daily infections, in response to various government policies in Korea. [33] develops a compartmental model to investigate the impact of vaccination coverage on different outcome metrics under the Omicron variant and a less transmissible variant. Importantly, neither work [31, 32, 33] models and studies screening strategies, which is the main focus of our paper.…”

“…[33] develops a compartmental model to investigate the impact of vaccination coverage on different outcome metrics under the Omicron variant and a less transmissible variant. Importantly, neither work [31, 32, 33] models and studies screening strategies, which is the main focus of our paper.…”

Modelling the Impacts of Immigrants on COVID 19 Transmission Dynamics with Control Measures

“…Some countries around the world tightened restrictions on international arrivals to slow the spread of the disease (Gwee et al 2021). Indeed, COVID-19 has slowed economic growth, reduced the number of tourists, as well as technological transfers (Tchoumi et al 2022). Some studies have been conducted on the transmission of COVID-19 in the presence of immigrants.…”