People with neo-coronary pneumonia may detoxify two or three days before they have symptoms

a new model study published in nature-medicine, an international academic journal of natural research, suggests that patients with neo-coronary pneumonia (COVID-19) may begin to excrete or secrete the new coronavirus (SARS-CoV-2) two or three days before the initial symptoms appear.The author of this medical research paper by modeling the point at which the new coronavirus spreads is Liu Haoran of the WHO Centre for Infectious Disease Epidemiology and Control at the University of Hong Kong. The researchers and colleagues surveyed the virus discharge time patterns of 94 patients with neo-coronary pneumonia at the Eighth People's Hospital in Guangzhou, and collected their pharynx swabs -- from the first symptom to the next 32 days -- and analyzed a total of 414 pharynx swabs and found that the patients had the highest viral load at the beginning of their symptoms.In addition, Liu and colleagues modeled the infectious characteristics of neo-corona pneumonia using another 77 "transmission pairs" of information from publicly available data. Each "transmission pair" consists of two patients with new coronary pneumonia with a clear epidemiological link, most likely one infected with the other. Based on model studies, the researchers concluded that infections began two or three days before symptoms of the new coronary pneumonia appeared, peaking at 0.7 days before the symptoms appeared. They estimate that 44% of secondary cases are infected in the pre-symptom stage, and that the virus's infectious capacity is expected to decline rapidly within seven days.According to the study, there are a number of factors that affect the effectiveness of new coronavirus prevention and control measures, including the interval between consecutive cases in the transmission chain and the time from exposure to infection to the ont of symptoms (incubation period). If the continuous interval is shorter than the incubation period, it means that the virus may have spread before the appearance of explicit symptoms. Therefore, the effectiveness of prevention and control measures taken to control the spread of infection may be compromised by the time symptoms appear.The authors noted that the limitations of the study include reliance on patients to recall the initial symptoms, which may introduce bias in the study, as there may be cognitive lag in the initial symptoms, according to a press release from Nature Research, which provided the paper to the media on the 15th. (
China News
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