What is the epidemic level of students who have been exposed to Hebei University?
Sub-dense contact Class A contacts refer to confirmed patients, those who have had contact with COVID-19 patients are close contacts, and those who have had close contact are sub-close contacts, all of which need to be isolated. Hebei University, located in Baoding City, Hebei Province, is a key comprehensive university jointly established by the Ministry of Education and the People's Government of Hebei Province.