Guangdong province is going all out to fight COVID-19 after two new confirmed locally transmitted cases and four asymptomatic cases were reported in the province on Wednesday.

Li Xi, Party secretary of Guangdong, has urged related departments in the province to prioritize prevention and control of the coronavirus in the weeks ahead.

"More effective and concrete measures must be introduced to prevent and control the spread of the coronavirus in the province, which has a population of more than 120 million," Li said at a conference in Guangzhou on Wednesday.

The two confirmed cases on Wednesday were in Guangzhou, the provincial capital, which together with Shenzhen each reported two new asymptomatic cases, according to a statement released by the Guangdong Provincial Health Commission.

Guangdong also reported 12 imported cases on Wednesday, and the authorities called on related departments and residents to pay special attention to preventing imported coronavirus cases from spreading, the statement said.

Guangzhou has reported a total of four locally transmitted confirmed cases, plus five asymptomatic cases, since the first confirmed patient, a 75-year-old woman surnamed Guo, was reported last Friday, said Chen Bin, deputy director of the city's health commission.

Chen said that all of the patients were contacts of Guo and belong to the same chain of infection.

In addition to Guo, the confirmed cases include Guo's husband, surnamed Lu, another local resident surnamed Song, 74, and Song's 11-year-old grandson surnamed Xu. Song once had breakfast at a restaurant with Guo.

All of the patients have been sent for treatment to Guangzhou No 8 People's Hospital, which is designated for COVID-19 patients, and all are in a stable condition.

To prevent and control the coronavirus, related departments have launched further epidemiological investigation and disinfection measures at public venues the patients have visited since last Friday, according to Chen.

More than 540,000 residents of the city have so far received nucleic acid tests, said Chen.

"Meanwhile more than 8.67 million local residents had been vaccinated in the city by 2 pm on Thursday," she said.

Lin Jun, vice-director of Liwan district, said the local authorities had organized mass nucleic acid testing for all residents in the district since Wednesday.