Medical workers take swab samples from residents for COVID-19 nucleic acid testing in Zhangjiajie, central China's Hunan province, Aug 4, 2021. (CHEN SIHAN / XINHUA)

BEIJING - China's current COVID-19 containment measures are effective against the Delta variant, a health official said Thursday.

COVID-19 vaccines administered across the country - having surpassed 1.72 billion doses as of Wednesday - also demonstrate good preventive and protective effects against the Delta variant, He Qinghua, an official with the National Health Commission (NHC), said at a press conference in Beijing.

He Qinghua, an official with the National Health Commission, said that the current vaccines can reduce the risk of transmission, and effectively cut the incidence of severe symptoms and lower fatality rate

Research results and clinical experience at home and abroad showed that the variant had yet led to fundamental changes in the biological characteristics of the COVID-19 virus, and scientists are basically clear about how the virus is transmitted, the official said.

He said that the current vaccines can reduce the risk of transmission, and effectively cut the incidence of severe symptoms and lower fatality rate.

The latest resurgence of COVID-19 can be effectively contained in a short time if response measures are strictly enforced, He added.

China has earlier successfully stopped the spread of the Delta variant in multiple densely-populated regions with high population mobility in Guangdong Province, which proves measures including vaccination, wearing masks, washing hands frequently, keeping social distance, and avoiding crowded places are effective, the official said.

Semester postponement 

Another official said schools in areas classified as having medium or high risks of COVID-19 outbreaks may delay the start of the upcoming autumn semester.

Liu Peijun, an official with the Ministry of Education, told the press conference that COVID-19 prevention and control is the top priority for the new semester's work.

Education authorities across the country, in cooperation with medical institutions, will organize vaccinations for students aged between 12 to 17 properly and safely upon informed consent from the students as well as their parents and guardians, Liu said.

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China also is stepping up efforts to prevent the spread of COVID-19 in tourism and culture sectors as the country is experiencing a new wave of COVID-19 outbreaks during its peak tourist season, Yu Changguo, an official with the Ministry of Culture and Tourism, said at the same press conference.

The Chinese mainland on Wednesday reported 62 new locally-transmitted COVID-19 cases, the NHC said in its daily report Thursday.

The capital Beijing, which recently classified two residential compounds as COVID-19 medium-risk areas, imposed strict entry and exit controls, asking residents to minimize travel and avoid gatherings.

Zhengzhou, capital of central China's Henan province, has launched citywide nucleic acid testing, requiring people leaving the city to show proof of negative nucleic acid tests taken within 48 hours.

Recent COVID-19 cases reported in Zhengzhou were highly homologous with an imported case under treatment at a local hospital, Guo Yanhong, an official with the NHC, said at the same conference.

Patients in the capital city, though also infected with the highly infectious Delta variant of the coronavirus, were not connected to the recent resurgence in Nanjing, Guo added.

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Other cities like Wuhan and Nanjing have also launched mass COVID-19 testing campaigns.