Spikes in coronavirus cases have prompted a flood-hit Chinese city to start mass testing and a popular tourist destination to cut traffic to try to contain the spread of the deadly disease. Less than a fortnight after it was hit by floods, Zhengzhou, the capital of the central province of Henan is battling a crop of Covid-19 cases at one of its hospitals. Zhengzhou reported 12 local confirmed cases and 20 asymptomatic cases on Saturday, after its first asymptomatic case report on Friday. Zhao Dongyang, deputy director of the province’s disease control centre, said on Sunday that DNA sequencing indicated the outbreak was caused by the Delta variant of the virus and the city had to take tougher preventive measures. Zhang Ruoshi, deputy head of Henan’s health commission, said the outbreak was in the early stages but it still posed a grave challenge to Covid-19 prevention and control”. Henan authorities have sent 5,400 medical workers to Zhengzhou to help with testing of the city’s roughly 14 million people, the first round of which is expected to be completed on Tuesday. About 700,000 coronavirus vaccine doses have been sent to Zhengzhou to expand vaccination, including of teenagers. Last month the city saw record levels of rain, which caused extensive flooding across Henan province , killing at least 99 people and affecting more than 11 million residents. The city has suspended operations at the Sixth People’s Hospital, which has been designated to treat imported infections. Wang Songqiang, director of the Zhengzhou Disease Prevention and Control Centre, said on Saturday night that the disease had spread quickly and those affected included cleaners and medical workers. Two officials, one from the city’s health commission and one from the hospital, have been removed from their positions. Nationwide, China reported 53 local confirmed cases and 25 local asymptomatic ones on Saturday, according to the National Health Commission. The nationwide caseload is expected to keep rising this week after a cluster of cases that originated in Nanjing spread to more than 20 cities, infecting over 200 people. Haikou, the capital of Hainan province, became the latest city reporting one confirmed case on Sunday. Zhangjiajie, in Hunan province, is another hotspot, with seven confirmed cases as of Saturday. Municipal authorities said on Sunday that all traffic had been banned in the city except vehicles for disease control, logistics, ambulance and firefighting services. Confirmed cases were found among employees at travel agencies, and there are concerns that the infection will continue to spread to other places. Feng Zijian, a researcher with the Chinese Centre for Disease Control and Prevention, said on Saturday that initial assessments indicated the outbreak in Zhangjiajie was related to the Nanjing airport cluster. Beijing reported two new confirmed case and one asymptomatic case on Sunday, all from one family who travelled to Zhangjiajie last week.