How is the five high epidemics in Ruzhou infected?

It is understood that at 65438 on the evening of October 4th, 2022/kloc-0, the information released by the office of COVID-19 epidemic prevention and control headquarters in Ruzhou showed that there were 39 cases of asymptomatic COVID-19 infection in Ruzhou, and 37 cases were fifth-grade students in Ruzhou, who were close contacts of the case 17. Both of them are from Shiqiao Village, Zhifang Town, Ruzhou City. Case 38 is a student from Runan Campus of Youdao Experimental School in Ruzhou City, and is a close contact of case 16. Both of them are from Chequ Village, Zhifang Town, Ruzhou City. Both students and their close contacts may be family members. The two students were in their respective schools before being diagnosed as centralized isolation.