Table 3.

Some major events related to COVID-19 vaccines.

Time	Major event	Highest attentiveness percentage	Lasting days
July 14, 2020 (t1)	“An mRNA vaccine against SARS-CoV-2—preliminary report” [40] was published.	4.27%	14
August 12, 2020 (t2)	“Phase I/II study of COVID-19 RNA vaccine BNT162b1 in adults” [41] was published.	4.78%	12
November 9, 2020 (t3)	Pfizer and BioNTech announced phase III results [42].	9.78%	6
December 15, 2020 (t4)	The first mass vaccination program started globally [43].	17.48%	21
April 10, 2021 (t5) selected from March to April, 2021	More and more vaccine-related studies and news were reported (see Multimedia Appendix 1).	18.92%	46