- Correspondence to Dr Shamez N Ladhani, Immunisation and Countermeasures Division, Public Health England, London, NW9 5EQ, UK;
- Received November 21, 2019
- Revised January 14, 2020
- Accepted January 15, 2020
- First published February 6, 2020.
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.