Emerging climate-sensitive infections of the North

Abstract

As the terrestrial realms of the Arctic thaw with climate change, populations of relative southern infectious diseases carried by vector organisms such as ticks and mosquitoes may migrate, expand and/or in other ways respond to the resulting landscape transitions, and transmit onto humans and animals of the far North. The OneHealth effects of potentially expanding climate sensitive infections (CSI’s) constitute a serious global threat. To identify potential CSI’s, data concerning a selection of human infections were procured from national health reporting systems to cover the current thirty-year climate reference period (onto 2016) from western Greenland to the pacific coast of Russia, from approximately 55 to 80 degrees north. The diseases chosen to represent different transmission processes, e.g. via vector organisms bound to water, air, and/or soil environments, were borreliosis, brucellosis, cryptosporidiosis, leptospirosis, Puumala haemorrhagic fever, Q-fever, tick-borne encephalitis, and tularaemia. Inferential results indicate that 88% (7/8) of these infections are changing systematically with respect to incidence levels and/or geographic distribution, at local or regional scales within the study area, and that they therefore should be considered as being potentially climate sensitive. It is hence likely that many northern societies will experience changing CSI exposure. In addition, for each of the selected infections, the geographic distribution of their respective thirty-year average incidences was used to define “diseases climates” for future reference. Inconsistencies across national health reporting systems, as well as the current (late 2023) exclusion of Russian observatory networks, are seriously constraining the possibilities to infer international climate-related epidemiological trends.