Effects of conservation management of landscapes and vertebrate communities on Lyme borreliosis risk in the United Kingdom

Abstract

Landscape change and altered host abundance are major drivers of zoonotic pathogen emergence. Conservation and biodiversity management of landscapes and vertebrate communities can have secondary effects on vector-borne pathogen transmission that are important to assess. Here we review the potential implications of these activities on the risk of Lyme borreliosis in the United Kingdom. Conservation management activities include woodland expansion, management and restoration, deer management, urban greening and the release and culling of non-native species. Available evidence suggests that increasing woodland extent, implementing biodiversity policies that encourage ecotonal habitat and urban greening can increase the risk of Lyme borreliosis by increasing suitable habitat for hosts and the tick vectors. However, this can depend on whether deer population management is carried out as part of these conservation activities. Exclusion fencing or culling deer to low densities can decrease tick abundance and Lyme borreliosis risk. As management actions often constitute large-scale perturbation experiments, these hold great potential to understand underlying drivers of tick and pathogen dynamics. We recommend integrating monitoring of ticks and the risk of tick-borne pathogens with conservation management activities. This would help fill knowledge gaps and the production of best practice guidelines to reduce risks.This article is part of the themed issue ‘Conservation, biodiversity and infectious disease: scientific evidence and policy implications’.

Occurrence of Borrelia and Borreliella species in Ixodes ricinus collected from roe deer in northwestern Spain

“…Nevertheless, although roe deer are not considered competent reservoir hosts for Borreliella spp. because they do not develop systemic infection and transmit the infection to susceptible ticks (Kjelland et al, 2011;Sprong et al, 2012), their role as host for ticks makes them central to the geographical distribution of ticks and transmitted agents such as LB spirochetes (Millins et al, 2017). Indeed, several studies have shown a positive relationship between both cervid and tick populations and therefore the risk to acquire LB (Kjelland et al, 2011;Sprong et al, 2012).…”

Null expectations for disease dynamics in shrinking habitat: dilution or amplification?

“…Stage-specific transmission dynamics has also been shown to impact disease dynamics [88]. Incorporating vector populations into these null models and how these respond to changes in habitat area and host availability in these models will be an essential next step [89,90].…”

Conservation, biodiversity and infectious disease: scientific evidence and policy implications

“…Kilpatrick et al [24] synthesize knowledge on Lyme disease ecology and describe the data gaps that have created controversy in the Lyme disease system. In bringing together authors from disparate viewpoints and diverse places, they lay the groundwork for future research to resolve major controversies and improve control.…”