PMC:7039910 / 17677-17822
Annnotations
{"target":"https://pubannotation.org/docs/sourcedb/PMC/sourceid/7039910","sourcedb":"PMC","sourceid":"7039910","source_url":"https://www.ncbi.nlm.nih.gov/pmc/7039910","text":"ties, including Beijing, Shanghai, Guangzhou, and Shenzhen16. In addition, pressure on transmission control caused by the population migration af","tracks":[]}