Funding for this research was provided by:
Medical Research Council
Natural Environment Research Council
National Institute for Health Research Health Protection Research Unit (NIHR HPRU) in Environmental Change and Health
Text and Data Mining valid from 2019-03-13
Received: 27 December 2017
Accepted: 20 February 2019
First Online: 13 March 2019
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: Not Applicable<b>.</b>
: The authors declare that they have no competing interests.
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