"The friend who ate together at the dinner table yesterday tested positive for COVID-19 Antigen today, but I haven't been positive, so I wonder if I can avoid the second wave?" Recently, many readers reported to the media that more colleagues and friends around have been infected with COVID-19. To this end, reporters from Yangcheng Evening News visited multiple hospitals in Guangzhou to understand the current situation of "second positive" and "first positive". "Eryang" is mainly a mild disease, and some of it is the first infection. It is aimed at the increasing infection of COVID-19. On April 24, Yan Wensen, the deputy chief physician of the Department of Respiratory and Critical Care Medicine of the Second People's Hospital of Guangdong Province, told reporters that, "Recently, we have contacted nearly 20 COVID-19 infection positive patients in the outpatient department, including five or six COVID-19 patients with secondary infection." "With the decline of antibody concentration in infected people, COVID-19 infection may have a regular and seasonal situation of" cluster infection "every 3-6 months." Professor Peng Jie, director of the Center for Difficult and Complicated Infectious Diseases of Southern Hospital of Southern Medical University, said, The recent increase in the number of people infected with COVID-19 is the embodiment of this regular infection. After this infection with COVID-19, there will be fever, cough, headache, muscle pain, nasal congestion, runny nose, sore throat and other symptoms. Many people thought it was flu at first. "They tested the antigen at home or at the outpatient clinic before they found it was COVID-19 infection. However, the symptoms of the second infection were much lighter than the first infection, mainly moderate and low fever, and the fever subsided in a day or two. And the symptoms of the first Yang were not serious," Yan Wensen said. "Judging from the current situation of fever clinics, the overall focus is on mild symptoms, usually fever and flu like symptoms. Some of the positive cases are the first infection." Huang Jing, director of the fever clinic of Guangdong Provincial People's Hospital, said that because the previous time was also the peak period of influenza, people were generally cautious, and some would also come to the fever clinic for medical treatment, so it was timely to find COVID-19 infection. People who have never been positive are at high risk of infection, especially a family "I haven't received serious patients here, and the symptoms of COVID-19 patients in fever clinics are relatively mild." Deng Xilong, director of the Department of Severe Medicine of the Eighth Affiliated City Hospital of Guangzhou Medical University, said. In response to the generally mild symptoms of two positive cases, Li Feng, Deputy Director of the Institute of Infectious Diseases at the Eighth Affiliated Hospital of Guangzhou Medical University, said, "Based on existing data, after being infected with Omicron, especially the previous wave of epidemic strain BA. 5 in Guangzhou, the antibodies in the body still have a certain degree of neutralization protection against different subtypes of the same virus strain, and can resist the attack of the new Omicron epidemic strain in the short term, Even if secondary infection occurs, the immunological memory stored in the body can be activated immediately, effectively reducing the severity of infection. "At present, the Ct values of COVID-19 infected people we found are low (generally the lower the value, the more viral load in the body), so people who have not been positive are at a higher risk of infection, especially the same family." Yan Wensen said, "It is recommended that people who have not been positive, especially those who have not been vaccinated, get vaccinated as soon as possible." Huang Jing reminded that if there are positive cohabitants in the family, it is recommended to do a good job of window opening and ventilation. Especially in the south, do not turn on the air conditioning for a long time. Open windows at least twice a day for ventilation, each time for half an hour, to ensure indoor air circulation. Yang