Table 2.

Group of key population and attack rate of each group

Group	Exposed populations	Quarantine protocol	Tracing techniques	Risk level	Total no	No. of cases	Attack rate (%)
1	Workers at the XFD market	Centralized quarantine	Onsite	High	3311	169	5.10
1.1	Workers at the BMTH	Centralized quarantine	Onsite	High	838	119	14.20
1.2	Workers at the XFD market other than BMTH	Centralized quarantine	Onsite	High	2473	50	2.02
2	Visitors to the XFD market on June 12th	Centralized quarantine	Onsite	Medium	7689	8	0.10
2.1	Visitors to the BMTH market	Centralized quarantine	Onsite	Medium	1078	8	0.74
2.2	Visitors to the XFD market other than BMTH	Centralized quarantine	Onsite	Medium	6611	0	0
3	Visitors to XFD between May 30th and June 11th	Home quarantine	Big data	Low	535 000	95	0.02
3.1	Visitors to the BMTH market	Home quarantine	Big data	Low	75 000	64	0.09
3.2	Visitors to the XFD market other than BMTH	Home quarantine	Big data	Low	460 000	31	0.007

BMTH Beef and Mutton Trading Hall, XFD Xinfadi