every four days, the nucleic acid test is done once a cycle. Hanjiang District, Yangzhou City, Jiangsu Province belongs to the normalization area, and the work of Yangzhou epidemic situation requires that the nucleic acid detection be done once every four days in the normalization area. Yangzhou, known as Guangling, Jiangdu and Weiyang in ancient times, is a prefecture-level city under the jurisdiction of Jiangsu Province and a type II big city [62]. It is an important part of Jiangsu Yangtze River Economic Belt, a member city of Nanjing Metropolitan Area and a city in the center of the Yangtze River Delta. It is the food capital of the world, the canal capital of the world, the cultural capital of East Asia, the first batch of national historical and cultural cities and a scenic tourist city with traditional characteristics.