The basic reproduction number and the probability of extinction for a dynamic epidemic model.

Math Biosci

School of Mathematics, University of Manchester, Alan Turing Building, Oxford Road, Manchester M13 9PL, UK.

Published: March 2012

We consider the spread of an epidemic through a population divided into n sub-populations, in which individuals move between populations according to a Markov transition matrix Σ and infectives can only make infectious contacts with members of their current population. Expressions for the basic reproduction number, R₀, and the probability of extinction of the epidemic are derived. It is shown that in contrast to contact distribution models, the distribution of the infectious period effects both the basic reproduction number and the probability of extinction of the epidemic in the limit as the total population size N→∞. The interactions between the infectious period distribution and the transition matrix Σ mean that it is not possible to draw general conclusions about the effects on R₀ and the probability of extinction. However, it is shown that for n=2, the basic reproduction number, R₀, is maximised by a constant length infectious period and is decreasing in ς, the speed of movement between the two populations.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.mbs.2012.01.002DOI Listing

Publication Analysis

Top Keywords

basic reproduction
16
reproduction number
16
probability extinction
16
infectious period
12
number probability
8
transition matrix
8
number r₀
8
r₀ probability
8
extinction epidemic
8
basic
4

Similar Publications

CT-sensitized nanoprobe for effective early diagnosis and treatment of pulmonary fibrosis.

J Nanobiotechnology

January 2025

Nurturing Center of Jiangsu Province for State Laboratory of AI Imaging & Interventional Radiology; Basic Medicine Research and Innovation Center of Ministry of Education, Medical School of Southeast University, 87 Dingjiaqiao, Nanjing, 210009, China.

Early diagnosis is critical for providing a timely window for effective therapy in pulmonary fibrosis (PF); however, achieving this remains a significant challenge. The distinct honeycombing patterns observed in computed tomography (CT) for the primary diagnosis of PF are typically only visible in patients with moderate to severe disease, often leading to missed opportunities for early intervention. In this study, we developed a nanoprobe designed to accumulate at fibroblastic foci and loaded with the CT sensitizer iodide to enable effective early diagnosis of PF.

View Article and Find Full Text PDF

Infertility has emerged as a significant global health concern. Assisted reproductive technology (ART) assists numerous infertile couples in conceiving, yet some experience repeated, unsuccessful cycles. This study aims to identify the pivotal clinical factors influencing the success of fresh embryo transfer of in vitro fertilization (IVF).

View Article and Find Full Text PDF

Frozen versus fresh embryo transfer in women with low prognosis for in vitro fertilisation treatment: pragmatic, multicentre, randomised controlled trial.

BMJ

January 2025

State Key Laboratory of Reproductive Medicine and Offspring Health, Centre for Reproductive Medicine, Institute of Women, Children and Reproductive Health, Shandong University, Jinan, China

Objective: To test the hypothesis that a freeze-all strategy would increase the chance of live birth compared with fresh embryo transfer in women with low prognosis for in vitro fertilisation (IVF) treatment.

Design: Pragmatic, multicentre, randomised controlled trial.

Setting: Nine academic fertility centres in China.

View Article and Find Full Text PDF

fos genes in mainly invertebrate model systems: A review of commonalities and some diversities.

Cells Dev

January 2025

Departamento de Neurobiología del Desarrollo y Neurofisiología, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus UNAM Juriquilla, Querétaro, Querétaro, Mexico. Electronic address:

fos genes, transcription factors with a common basic region and leucine zipper domains binding to a consensus DNA sequence (TGA{}TCA), are evolutionarily conserved in eukaryotes. Homologs can be found in many different species from yeast to vertebrates. In yeast, the homologous GCN4 gene is required to mediate "emergency" situations like nutrient deprivation and the unfolded protein response.

View Article and Find Full Text PDF

Hemolysis, elevated liver enzymes, low platelet count (HELLP) syndrome is a severe complication of preeclampsia (PE), with a higher incidence rate in people living at high altitudes, such as Tibet area. Maternal HELLP syndrome is associated with an elevated neonatal mortality rate. The purpose of this study was to investigate the predicting factors for neonatal outcomes with maternal HELLP syndrome.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!