Is biodiversity good for your health? Birds as bioindicators of Lyme disease risk in the environment.

Location: University of Exeter, Penryn Campus, Penryn, Cornwall TR10 9FE

This project is one of a number that are in competition for funding from the NERC Great Western Four+ Doctoral Training Partnership (GW4+ DTP). The GW4+ DTP consists of the Great Western Four alliance of the University of Bath, University of Bristol, Cardiff University and the University of Exeter plus five Research Organisation partners: British Antarctic Survey, British Geological Survey, Centre for Ecology and Hydrology, the Natural History Museum and Plymouth Marine Laboratory. The partnership aims to provide a broad training in earth and environmental sciences, designed to train tomorrow’s leaders in earth and environmental science. For further details about the programme please see http://nercgw4plus.ac.uk/

Project details

Biodiversity can influence the emergence and transmission of infectious diseases and thus have a direct impact on human health. Lyme disease, transmitted by ticks, is the most common vector-borne disease in the northern hemisphere. It is caused by Borrelia spirochetes, with several bird and rodent species serving as natural reservoirs. In North America, high diversity of mammalian tick hosts has been linked to reduced Borrelia burgdorferi prevalence, resulting in lower Lyme disease infection risk for humans. This finding has become a textbook example for why biodiversity is good for people’s health and a utilitarian argument for the value of biodiversity conservation. However, a different suite of Borrelia strains and host species occur in Europe and as yet nothing is known about the associations between biodiversity and infection risk within this system. As cases of Lyme disease reach record numbers in the UK, understanding the possible regulatory effects of vertebrate biodiversity is essential.

Project Aims and Methods

This project will establish the UK distribution of ticks and Borrelia, and identify the ecological factors driving spatial variation in disease risk. Since Borrelia garinii, a bird host specialist, is particularly common in the UK, it will also examine the value of bird diversity in buffering human exposure to Lyme disease.

The British Trust for Ornithology (BTO) is a world leader in using citizen science to monitor wildlife populations. The student will receive expert guidance in survey design and volunteer engagement in order to coordinate a UK-wide citizen science tick survey aligned with the BTO’s existing national bird monitoring scheme, the Breeding Bird Survey. A simple, standardised tick dragging technique will be used by the volunteers to collect ticks, and molecular analysis will be performed to determine Borrelia infection status. Ecological modelling will be used to identify the main determinants of spatial variation in disease risk, and to test whether measures of bird community diversity are associated with reduced prevalence of Borrelia infection in ticks.

This project will result in the largest, systematic UK assessment of Borrelia prevalence to date and will be the first to test if bird biodiversity is a bioindicator of Lyme disease risk in Europe. The outcomes will improve our understanding of the value of biodiversity for human health.

The student’s involvement in project design and choice of research direction is expected and encouraged.

Training

The student will obtain training in project design and management, molecular laboratory techniques (e.g. (q)PCR, sequencing), ecological modelling, statistical data analysis and scientific publishing at the University of Exeter and during secondments at BTO and PHE. At BTO and Cardiff University the student will gain experience in the coordination and management of large-scale citizen science projects and public outreach.