Understanding how temperature shifts could impact infectious disease

Abstract

Climate change is expected to have complex effects on infectious diseases, causing some to increase, others to decrease, and many to shift their distributions. There have been several important advances in understanding the role of climate and climate change on wildlife and human infectious disease dynamics over the past several years. This essay examines 3 major areas of advancement, which include improvements to mechanistic disease models, investigations into the importance of climate variability to disease dynamics, and understanding the consequences of thermal mismatches between host and parasites. Applying the new information derived from these advances to climate–disease models and addressing the pressing knowledge gaps that we identify should improve the capacity to predict how climate change will affect disease risk for both wildlife and humans.

Temperature and pathogen exposure act independently to drive host phenotypic trajectories

“…[9,[14][15][16][17]). Population persistence will therefore be shaped by how temperature change and pathogen exposure directly interact to shift multiple facets of a host's phenotype, in addition to the complex role that temperate plays in driving pathogen transmission strategies [18][19][20] and host-pathogen interactions more broadly [21,22].…”

Movement can mediate temporal mismatches between resource availability and biological events in host–pathogen interactions

“…While climate warming might induce mismatch effects negatively affecting host life history, climate warming might have direct effects on the pathogen, too, amplifying either positive or negative consequences on the host. Indeed, it is reasonable to expect that some diseases will adapt to changing environmental conditions and potentially increase in prevalence (Rohr & Cohen, 2020; Thomas, 2020). However, here we focus on mismatch effects on host life history.…”

How will mosquitoes adapt to climate warming?

“…This encompasses many taxa that threaten human health and well-being, including agricultural and forest pests, wildlife and plant pathogens, and disease vectors, for which accurately predicting distributions under climate change is critical for protecting human and animal health. Several prominent reviews have found that climate change is expected to increase, decrease, or, most commonly, shift the distributions of these taxa due to nonlinear and interactive effects of temperature and other climatic factors ( Porter et al, 1991 ; Harvell et al, 2002 ; Deutsch et al, 2008 ; Rohr et al, 2011 ; Altizer et al, 2013 ; Lafferty and Mordecai, 2016 ; Pinsky et al, 2019 ; Lehmann et al, 2020 ; Rohr and Cohen, 2020 ). However, these predictions largely assume that species climate responses are fixed, ignoring the potential for adaptive responses.…”