Impacts of climate change on the distributions of allergenic species

All species survive within a limited climatic range, with temperature and moisture availability critically influencing distribution, abundance, and behaviour. As climate changes, therefore, populations and species may adapt in situ to new conditions or may undergo shifts in demographic patterns and distributions (Bellard et al., 2012). Indeed, palaeoecological data provide evidence that distribution shifts were a common response among plants during previous episodes of climate change, altering community composition and creating new assemblages (Willis and MacDonald, 2011). Similar shifts are expected in response to anthropogenic climate change.

While a plethora of studies have assessed climate-driven distribution shifts, few have taken the perspective of allergen-producing (AP) species and ramifications for human health. Yet distribution shifts will alter the frequency of human encounters with AP species, with consequences for health care and associated economic costs. Here, we undertake a review of recent distribution shifts among AP plant and arthropod species, briefly introduce tools used to forecast future shifts, and discuss the extent to which species distributions may reconfigure as the century progresses. Although a global review, examples from the Northern Hemisphere predominate with comparatively fewer studies having been undertaken in the Southern Hemisphere.