License:
Since January 2020 Elsevier has created a COVID-19 resource centre with free information
in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre
is hosted on Elsevier Connect, the company's public news and information website.
Elsevier hereby grants permission to make all its COVID-19-related research that is
available on the COVID-19 resource centre - including this research content - immediately
available in PubMed Central and other publicly funded repositories, such as the WHO
COVID database with rights for unrestricted research re-use and analyses in any form
or by any means with acknowledgement of the original source. These permissions are
granted for free by Elsevier for as long as the COVID-19 resource centre remains active.