Etiological investigation on the epidemic of upper respiratory tract infection among children in Changshu, Jiangsu

  Objective  To analyze the pathogen of an outbreak of acute respiratory tract infection(ARTI) in a kindergarten in Changshu, Jiangsu.

  Methods  In September 2021, throat swabs were collected from children with ARTI at a kindergarten in Changshu, Jiangsu, then 18 respiratory pathogens were screened on these samples. The VP4-VP2 gene of rhinovirus with the highest detection rate were amplified by nested PCR. After the genotype of rhinovirus was analyzed using software MEGA 7.0, the phylogenetic tree was constructed according to the sequence of VP4-VP2.

  Results  A total of 51 pharyngeal swabs were collected from pediatric patients, including 24 boys and 27 girls. The main clinical symptoms were runny nose and sore throat. The screening results of 18 respiratory pathogens showed that 41 samples were positive for virus, accounting for 80.39% (41/51). The detection rate of single virus was 64.71% (33/51), and the co-infection rate of viruses was 15.69% (8/51). The detection rate of rhinovirus was the highest in both single virus positive samples (42.43%,14/33) and co-infection samples(87.5%, 7/8). Other viruses, including parvovirus B19 (18.18%, 6/33), boca virus (15.15%, 5/33), coronavirus 229E (6.06%, 2/33), human metapneumovirus, influenza B virus, adenovirus, respiratory syncytial virus and coronavirus OC43 and NL63 (3.03%, 1/33), were also detected respectively. After 12 VP4-VP2 fragments from 21 rhinovirus positive samples were amplified, the sequence analysis showed that the 12 strains belonged to 4 serotypes of rhinovirus A including 9 strains of A49, 1 strains of A19, 1 strain of A22 and 1 strain of A41.

  Conclusion  Many viruses were detected in swabs samples from pediatric patients in an outbreak of ARTI in a kindergarten in Changshu. Rhinovirus A49 had the highest detection rate, which might be closely related to the outbreak of ARTI in a kindergarten in Changshu.