Nucleic acid testing is generally referred to as novel coronavirus nucleic acid testing, which will not show a positive result for a common lung infection. Nucleic acid testing is used to detect novel coronavirus RNA by extracting tissue samples from the throat and nasal passages, and is usually only positive if the novel coronavirus is present. Nucleic acid tests for common lung infections are usually positive only if novel coronaviruses are present. Common lung infections are inflammatory diseases caused by lung bacteria, Chlamydia pneumoniae, and other infections that do not contain novel coronaviruses, so nucleic acid tests for common lung infections will not show a positive result. Since the symptoms of lung infection and novel coronavirus are similar, it is easy to be confused and misdiagnosed. Therefore, if symptoms such as fever, dry cough, and difficulty in breathing occur, it is recommended to consult a doctor promptly to avoid delaying the disease, and if necessary, conduct nucleic acid test and chest CT to rule out infection with novel coronavirus.