Prof. Zhou Hongwei shared diagnosis experience of COVID-19 at live broadcast.



Prof. Zhou Hongwei is the Director of Division of Laboratory Medicine, Zhujiang Hospital of Southern Medical University and the Vice Chairman of Laboratory Medicine branch of Guangdong Medical Association.


Research directions and achievements: Prof. Zhou Hongwei and his team committed to understand the host-associated microbes (intestine, oral cavity, reproductive tract, etc.) to understand the complexity of microbial ecologies and molecular mechanism underly, and to apply these theories to improve the practice of laboratory medicine. His efforts in human gut microbiome came up with a hypothesis named “REgion-dependent MIcrobiome DIagnosis (ReMiDi) (ReMiDi)”.

Prof. Zhou shared his opinions about COVID-19, the questions that the public was mostly concerned about.


Is there a risk of infection if we encounter a asymptomatic COVID-19 patient on the subway?


Recently, the CDC (Center for Disease Control and Prevention of China) has  pointed that a COVID-19 patient gets more severe condition with prolonged virus exposure and higher viral load. It seems that asymptomatic patients may be less infectious, but we cannot take it lightly and these patients are needed for surveillance. Although asymptomatic patients are very few, we still must protect ourselves. It is important to wear a mask and wash your hands frequently to protect yourself.


In a hospital at Hangzhou, a patient tested six times negative for COVID-19 nucleic acid tests and found positive during the seventh test. So why did the first six tests fail?


There are two issues that may contribute to this situation. One is the technological procedure and the other is the scientific issue. As for technology, any improper operation methods can lead to an unexpected test outcome, for example mistakes during sample collection, transportation, and labeling. Hopefully, these mistakes are reducing, as we are getting better at management. For scientific issue, if the amount of virus carried in the sample is lower than detection range, this will also lead to the 'false negative' outcome.


For a COVID-19 patient, what are the indexes for discharge from hospital?


Once there are no symptoms like COVID-19 he/she has to go through nucleic acid tests twice for alternative day, and both tests should be negative before he/she is discharged.


How could we ensure the accuracy of the nucleic acid test results for COVID-19?


In fact, the most important thing is to following doctor’s guidance. For example, among various types of tests in wards, if there are examinations such as nasopharyngeal swabs and pharyngeal swabs which may make you uncomfortable, but you shouldn't react too much to affect the doctor's operation. Because these examinations will not cause any harm to the human body.

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