Isolation. For jiexiu returnees, need to hold a 48-hour negative nucleic acid test certificate, in the city of the first drop point free of charge to carry out a nucleic acid test, all sweep "Shaanxi a code through the place code" to complete the information to fill in, check the big data trip card, carry out three days twice the nucleic acid test (interval of more than 24 hours), arrive in the city of the first three days do not participate in the meeting, exhibition , gatherings and other gathering activities, do not enter schools, child care institutions, nursing homes, orphanages and other specific institutions, try not to enter indoor confined places, do not participate in offline teaching, training and other activities.