Abstract: Abstract: Early, rapid and accurate diagnosis of disease is of great significance for the prevention of disease progression and the best clinical rational treatment program. Respiratory tract infections are the common and frequently occurring diseases in infants and preschool children, about 90 percent infections are of viral origin and etiology is very complex, but viral infection is often hard to distinguish from bacterial infection. Multiplex PCR has high sensitivity and specificity, and it is an effective tool for virus identification. It is widely used in the detection of respiratory infectious diseases. The common respiratory viruses causing respiratory infections include adenovirus (AdV), coronaviruses (CoV), human metapneumovirus (hMPV), influenza virus type A and B, parainfluenza virus type 1 (PIV 1), PIV 2, PIV 3, respiratory syncytial virus type A (RSV A), RSV B, rhinoviruses, enteroviruses and bocaviruses. If PCR reveals the presence of RNA derived from above respiratory virus, then an acute infection caused by the corresponding pathogen is probably present, and further treatment can be made accordingly by the clinician. In this paper, we reviewed the application of multiple PCR in the detection of typical and atypical pathogens in children's respiratory tract infection, and discussed the persistence of viral nucleic acid and effectiveness of virus clinical diagnostics.

Key words: multiplex PCR, respiratory tract, infections, virus, RNA