NANJING, July 28 (Xinhua) -- Nanjing, capital of east China's Jiangsu Province, reported 47 confirmed cases of COVID-19 and one asymptomatic infection on Tuesday, local authorities said Wednesday.
All the cases were categorized as locally transmitted, said the municipal health commission of Nanjing.
On Tuesday, the province reported a total of 48 locally transmitted confirmed cases -- 47 in Nanjing and one in the city of Suqian, according to the provincial health commission.
The surge in cases on Tuesday brought the total of novel coronavirus infections in Nanjing to 155, including 132 in the city's Jiangning District, the commission said.
Nanjing, a mega-city with a population of more than 9.3 million, has seen daily increases of locally transmitted COVID-19 cases since a few airport workers tested positive for coronavirus last week.
Citing epidemiological investigations, officials said the new cases in Nanjing were mostly found at the Nanjing Lukou International Airport and its proximity. New infections were also reported among flight passengers in other parts of China who have visited the airport.
On Tuesday, the city's center for disease control and prevention said the virus strain behind the recent spike in COVID-19 cases has been identified as the highly infectious Delta variant.
The outbreak has prompted the eastern Chinese city to launch all-inclusive nucleic acid testing campaigns and set up six air-inflated labs to improve its testing capabilities.