Footnotes

• Contributors All authors contributed to the content and writing of the editorial.

• Funding SW and GH work for the Health Protection Agency who receive funding from the Department of Health; the views expressed in this publication are those of the authors and not necessarily those of the Department of Health (England). KT is grateful to NIHR for providing funding for her fellowship award.

• Competing interests None.

• Provenance and peer review Commissioned; internally peer reviewed.