Shanghai authorities just held a press conference after the city reported two new locally transmitted COVID-19 cases on Sunday, here's what we know so far:

- The two cases from Sunday had close contact with previously confirmed patients and were detected during the quarantine period.

- Fifty-five people who have come into close contact with the two have been isolated for observation. Their first round of virus testing were negative.

- As of Monday morning, a total of 378 samples taken from food, objects and the environment linked to the two new cases tested negative.

- COVID-19 risk level in Yingqian Village of Zhuqiao Township in Pudong District was classified as low after no new case was reported there for 14 days.

- Virus testing for Shanghai Pudong International Airport's freight unit has swabbed 17,719 people. So far, results for 11,544 samples have been released which are negative. 

- Airport authorities told the press briefing that routine virus testing will be rolled out for freight workers and voluntary vaccination will be arranged for those who want to do so.  

Regarding Shanghai's local infection on November 9, authorities said a preliminary survey suggests the patient, a 51-year-old male porter working at the Shanghai Pudong International Airport, and one of his colleagues, who was also confirmed infected the following day but in Anhui Province, were both exposed to a contaminated aircraft container from North America on October 30.

The pair were not wearing masks while working inside the container and their COVID-19 gene sequences were highly similar.