Monitoring results of human adenovirus and influenza virus in 1,447 children cases of influenza-like illness
HUANG Chaoyang1,2, XIANG Xingyu1,2, ZHANG Siyu1, HUANG Yiwei1,2, ZENG Ge1, LI Wenchao1,2, WANG Xiaolei1, ZHAN Zhifei1,2
1. Hunan Provincial Center for Disease Control and Prevention, Changsha, Hunan 410153, China; 2. Hunan Provincial Key Laboratory of Microbial Molecular Biology, Changsha, Hunan 410153, China
Abstract:Objective To analyze the monitoring data of human adenovirus (HAdV) and influenza virus (IFV) in children cases of influenza-like illness (ILI) in Hunan Province, and to provide a reference basis for prevention and control of related diseases. Methods Throat swab samples of ILI cases from Fever Clinic of Hunan Children's Hospital from June 2019 to October 2020 were collected, and nucleic acids of HAdV and influenza A/B virus (IFV A/B) were detected by fluorescent polymerase chain reaction (PCR). Hexon gene sequences were amplified by PCR for HAdV nucleic acid positive specimens, and thensequenced, genotyped and constructed a phylogenetic tree. Specimens positive for IFV A/B nucleic acid were identified byfluorescent reverse transcription PCR (RT-PCR) for corresponding subtypes/lineages. Results A total of 1,447 swab samples from children cases of ILI were collected, and 108 samples were positive for HAdV nucleic acid, with the positive rate being 7.46%. 67 samples of 7 subtypes were further classified, including 28 samples of HAdV-3, 21 of HAdV-7, 9 of HAdV-4, 5 of HAdV-55, 2 of HAdV-2, and 1 of HAdV-1 or HAdV-14. The positive rate of IFV A/B nucleic acid was 7.81% in 113 samples, including 81 samples of IFV-A H3 subtype and 32 samples of influenza B virus Victoria lineage (BV). 3 samples were detected to be HAdV and IFV mixed infection. The HAdV and IFV positive rates of ILI samples in 2019 were 14.65% and 12.44% respectively, which were higher than those in 2020 (2.56% and 4.65% respectively). No statistically significant differences were found in the HAdV and IFV positive rates between male and female children patients. The positive rate of HAdV or IFV was statistically significant different among different age groups. Conclusion During the monitoring period, HAdV detected in the children cases of ILI in Hunan Province belonged to 7 subtypes, mostly HAdV-3 and HAdV-7, and IFV detected were mainly IFV-A H3 subtype and influenza B virus BV. HAdV and IFV infections are prevalent in children of all ages. Surveillance, prevention and control of HAdV and IFV should be strengthened to reduce the occurrence of related diseases.