Modelling the effects of travel and cross-immunity on pandemic risk

在20世纪和21世纪初，世界上的人员和货物长途旅行的数量有所增加，部分原因是旅游业和农业贸易的增长。这可能会增加流行病的风险，因为它允许病原体在遥远的社区之间传播，并在每个社区中引起感染。然而，交叉免疫，即感染一种疾病毒株可对其他毒株产生一定程度的免疫力的现象，可能意味着这种增强的病原体传播也会导致对其他毒株产生广泛的免疫力。正如Robin Thompson及其合作者在即将发表的一篇论文中所假设的那样，这可能导致一种机制，即高旅行率降低了由于先前被低毒力菌株感染而导致现有病原体的高毒力菌株大流行的风险。在我的博士学位中，我计划使用全球人类和其他生物种群的数学模型来评估这一假设可能成立的条件，以及对公共卫生政策的影响。我尤其希望阐明国际旅行和贸易是否会增加或减少大流行风险，以及已经在全球常见的病原体的新菌株是否会导致高死亡率的大流行。BBSRC的优先领域：动物健康、全球不确定性、农业和粮食安全

During the 20th and early 21st centuries, the world has seen an increase in the volume of long distance travel of people and goods, partially due to the growth of the tourism industry and in agricultural trade. This could plausibly increase the risk of pandemics by allowing pathogens to travel between distant communities and cause infections in each of them. However, cross-immunity, the phenomenon whereby infection with one strain of a disease provides some level of immunity against other strains, could mean that this enhanced pathogen spread also leads to widespread immunity to further strains. This may lead to a mechanism whereby high travel rates reduce the risk of pandemics of high virulence strains of existing pathogens due to prior infections by low-virulence strains, as hypothesised by Robin Thompson and collaborators in a forthcoming paper. In my DPhil, I plan to use mathematical models of global populations of humans and other organisms to assess the conditions under which this hypothesis could hold true, and what the implications are for public health policy. In particular, I hope to shed light on whether international travel and trade increase or decrease pandemic risk, and whether novel strains of already globally common pathogens can cause high mortality pandemics.BBSRC priority areas:Animal healthGlobal UncertaintiesAgriculture and Food Security