MEPI Subgroup Contributed Talks

Kamuela Yong

University of Hawaii - West Oahu

"A Mathematical Model of the Transmission of Rat Lungworm Disease"

The parasite Angiostrongylus cantonensis (AC), known as the rat lungworm hasa complex life cycle that begins when adult worms found in rats reproduce. Larvae exitthe rats through their feces where terrestrial gastropods such as snails and slugsbecome infected after consuming the rat feces. The life cycle is complete when ratsconsume infected snails and slugs. In this paper, we develop a mathematical model torepresent the transmission of AC through its life cycle. Numerical simulations areconducted to determine the factors that have the most impact on the transmission ofAC.

Artem Novozhilov

North Dakota State University

"Parametric heterogeneity in epidemiological models and modeling of COVID-19"

The theory of heterogeneous populations with parametric heterogeneity is a well developed area of mathematical modeling in biology. We say that our mathematical models describe parametric heterogeneity if we assume that the individuals in populations are heterogeneous with respect to some unchangeable with time parameter, such as birth of death rates or individual's susceptibility to an infectious disease for instance. In particular, the applications of this theory to epidemiological modeling yield very tractable analytically but also quite profound general results (e.g., that the epidemics is always less severe in heterogeneous populations compare to a homogeneous one). Recently, the observed avalanche of data related to the spread of COVID-19 around the world prompted the revival of interest in such heterogeneous models, a number of old results were rediscovered in different contexts, and also new results were obtained. In my talk I aim to present most of the known analytical results about heterogeneous populations with parametric heterogeneity from the general point of theory of heterogeneous populations and also discuss the dangers and pitfalls of applying this theory to the observed data. References: [1] Novozhilov, Math Biosc, 2008; [2] Novozhilov, Math Mod Nat Phen, 2012, Karev and Novozhilov, Math Biosc, 2019

Taeyong Lee

School of Mathematics and Computing (Mathematics), Yonsei University, Seoul, Republic of Korea

"The impact of control strategies for COVID-19 in South Korea"

The COVID-19 (Coronavirus disease) has spread since the first occurrence on 20 Jan 2020 in South Korea. To mitigate the transmission, KDCA (Korea Disease Control and Prevention Agency) has taken various types of control measures including school-closure and social-distancing. We developed an age-stratified compartmental model considering quarantine and isolation to describe the disease dynamics, which has been calibrated to the newly confirmed data from 20 Jan to 2 Apr 2020. The effectiveness of intervention measures was investigated under several scenarios through the simulation of the proposed model.The results predict that the epidemic threshold for increase of contacts is 1.6 times, which brings the net reproduction number to 1. A second outbreak is expected if the contacts between teenage increase more than 3.3 times when school opens. The reduction of average time until isolation and quarantine from three days to two would decrease cumulative cases by 60% and 47%, respectively. We also study the impact of control strategies considering transmission from asymptomatic or mild symptomatic people, because the infectiousness of those has been controversial.

Anjana Pokharel

Tribhuvan University Kathmandu, Nepal

"Modeling the Impact of Vaccination on the Transmission Dynamics of Measles in Nepal"

Measles is one of the highly contagious human viral diseases caused by the virus of paramyxovirus family. Despite availability of successful vaccine, measles outbreaks occur presumably due to the lack of compliance of vaccination. In this work, we will develop a deterministic mathematical model that explains the transmission dynamics of measles in Nepal. We will perform the numerical simulation to explore the impact of the vaccinations. We will also explain the qualitative behavior of the model.