To investigate the difference of laboratory indexes and clinical characteristics between children with Bordetella pertussis and respiratory virus coinfection and those with Bordetella pertussis infection alone.

From November 2016 to May 2017, a total of 42 throat swabs of children with pertussis were collected from Beijing Ditan Hospital, Capital Medical University. Total of 42 samples were qualitatively detected for Bordetella pertussis and other 17 kinds of respiratory virus by automatic nested multiplex PCR system. The detection results and clinical data of the children were analyzed, retrospectively. According to the pathogen detection results, patients were divided into children with Bordetella pertussis single detection (single detection group) and children with Bordetella pertussis and other respiratory virus codetection (codetection group).

Among the 42 specimens, 16 specimens (38.10%, 16/42) were isolated with Bordetella pertussis infection, 26 cases (61.90%, 26/42) with Bordetella pertussis and one or more respiratory viral pathogens. Total of 32 cases were detected with respiratory, among whom, 16 case (50%, 16/32) with human rhinovirus infection, while 6 case (18.75%, 6/32) with respiratory syncytial virus infection, 4 cases (12.50%, 4/32) with Parainfluenza virus and adenovirus and 2 cases (6.25%, 6/32) with influenza A virus infection. Laboratory examination results showed that there was no significant difference of white blood cell count between the two groups (t =-0.445, P = 0.661), but the proportion of lymphocytes in the codetection group increased (t =-2.913, P = 0.019). Compared with single detected group, the imaging changes of codetection group were mainly pneumonia (15/26, 57.69% vs. 2/16, 12.50%; P = 0.010). The highest body temperature was higher (t =-3.348, P = 0.030), the duration of cough (t = -3.141, P = 0.005) and the exacerbation period of cough (t =-4.748, P < 0.001) were longer than those of the control group, and the duration of cough was longer (t =-3.141, P = 0.005) than that of the control group. The length of hospitalization (t =-4.123, P = 0.001) and the course of antimicrobial treatment (t =-4.292, P < 0.001) codetection group were longer than those of single detection group, with significant differences.

The clinical symptoms of children with other respiratory viruses infection were more severe and the recovery time was longer than those with single Bordetella pertussis infection. In the treatment of pertussis, especially children with severe symptoms, attention should be paid to the possibility of coinfection with other respiratory viruses.