A single center study of the pathogenic characteristics of children with pertussis with other pathogens co-infection in a children's hospital in Chongqing, China.

Objective: Studying the pathogenic characteristics of children with pertussis with other pathogens co-infection. Methods: Retrospective analyzed the clinical data of the children with pertussis who were hospitalized at a Children's Hospital from 2016 to 2021. Results: Among the detected bacteria, there were 245 strains of Haemophilus influenzae (12.92%), 145 strains of Streptococcus pneumoniae (7.64%). Among the detected viruses , Respiratory syncytial virus(RSV) was the most common 441 strains (23.25%), followed by Parainfluenza virus 440 strains (23.19%). The average age of the co-infection group was smaller than that of the simple pertussis infection group(P<0.05). The percentages of children with pertussis co-infected with RSV, Staphylococcus aureus group, Escherichia coli , and Klebsiella pneumoniae in the 0-3 month age were 36.48%, 54.54%, 65.52%, and 78.95%, respectively. The proportions of children co-infected with Parainfluenza virus , and with Haemophilus influenzae at 3-6 months old were 29.55% and 36.49%, respectively. The percentage of children with pertussis with Mycoplasma pneumoniae co-infection aged 1 year or older were all 60%. RSV had a higher probability of co-infection in winter and spring (34.46%+36.21%), Parainfluenza virus had a higher probability of co-infection in spring and summer (83.48% (43.58%+39.91%). The median length of Hospitalization time in different co-infection groups was longer than that in the simple infection group. Conclusions： The top three pathogens in children with pertussis with other pathogen co-infections were RSV , Parainfluenza virus , and Haemophilus influenzae . RSV, Staphylococcus aureus. Escherichia coli and Klebsiella pneumoniae had the highest proportion at 0-3 months of age; Parainfluenza virus and Haemophilus influenzae had the highest proportion at 3-6 months of age, Mycoplasma was more common in children over 1 year old. RSV and Parainfluenza were more common in spring. Co-infection of other pathogens may lead to prolonged hospital stay. The more types co infection pathogens infected, the longer the hospital stay.