BEIJING — China reported one new local coronavirus infection on Wednesday as the country increasingly focuses on the possibility the virus might be spread on frozen food packaging.

The National Health Commission said the new case was detected in the northern port city of Tianjin just east of Beijing. The confirmed case, along with another person who tested positive without showing symptoms, were both previously quarantined under suspicion of having the virus.

Another seven cases were brought from outside the country, the commission reported, raising China’s total to 86,369 with 4,634 deaths since the virus was first detected in the central Chinese city of Wuhan late last year.

Authorities in several cities and provinces have reported detecting the virus on packaging of frozen seafood and meat imported from countries ranging from Germany to India.