Residents in the lockdown area in Zhengzhou, Central China's Henan Province, are restricted to only "enter but cannot leave" on August 4. Photo: CFP

Zhengzhou in Central China's Henan Province, a city that is just recovering from a deadly flood, has reported 112 local COVID-19 cases as of Thursday afternoon in the latest outbreak, according to local authorities.

The 112 patients include 19 symptomatic cases and 93 asymptomatic carriers, officials said at a press conference on Thursday evening.

Zhengzhou reported three symptomatic and eight asymptomatic cases on Thursday, after massive testing of all residents using nucleic acid tests according to local government official, Li Huifang.

The second round of citywide nucleic acid testing started on Thursday morning and is scheduled to be completed by Friday afternoon, Li added.

The Zhengzhou local government vowed to speed up the epidemiological investigation to prevent possible further transmissions of the coronavirus as soon as possible. 

Travel history of an infected patient surnamed Liu, a nurse at the Sixth People's Hospital in Zhengzhou, drew wide attention on Thursday, as she attended a wedding ceremony along with other 800 guests in the city on July 20, the newlyweds told WeVideo, a video news platform under The Beijing News.

The hospital Liu works at is a designated hospital for treatment of overseas arrivals who are infected with COVID-19. In this round of the virus resurgence, most cases reported in Henan are related to the hospital, said Zhang Ruoshi, Deputy Director of the Henan Health Commission.

There is one high-risk area and 21 medium-risk areas for COVID-19 in Zhengzhou as of Thursday, Li said. 

The city expanded its lockdown area on the same day, adding five streets to the list. All residents in the area are restricted to only "enter but cannot leave," according to local authorities in Zhengzhou.