Epidemiological characteristics and genomic analysis of respiratory adenovirus in Jining City from February 2023 to July 2024.

BACKGROUND

Human adenovirus (HAdV) infection can cause high fever, pneumonia, and even death, posing a serious threat to human health. This study analyzes the epidemiological characteristics and genetic features of respiratory adenovirus in Jining City from February 2023 to July 2024.

METHODS

From February 2023 to July 2024, 3,947 throat swab specimens were collected from influenza-like illness cases at Jining First People's Hospital and Rencheng District Maternal and Child Health Hospital. Real-time fluorescent quantitative PCR was used to detect HAdV nucleic acid. Whole-genome sequencing was performed on HAdV-positive samples. Phylogenetic trees were constructed for the whole genome, Penton base gene, Hexon gene, and Fiber gene of HAdV, and protein variation sites were analyzed.

RESULTS

The HAdV positivity rate in influenza-like cases in Jining City from February 2023 to July 2024 was 3.42% (135/3947), with higher positivity rates in younger age groups. HAdV positivity rates were higher between December 2023 and July 2024, while lower between January 2023 and November 2023. Whole-genome sequencing was performed on 47 HAdV samples, revealing 38 cases of HAdV-B and 9 cases of HAdV-C, with no HAdV-E detected. HAdV-B and HAdV-C co-circulated in Jining City from February to December 2023, while HAdV-B predominated from January to July 2024. All 38 HAdV-B sequences from Jining City are HAdV-3. In the phylogenetic trees of the whole genome, Penton base gene, Hexon gene, and Fiber gene of HAdV-B, all 38 HAdV-B strains from Jining City are located in the same evolutionary branch as the Chinese HAdV-3 candidate vaccine strain Guangzhou01. Compared to Guangzhou01, the RGD motif in Penton base and antigenic epitopes in Hexon of the 38 HAdV-B strains from Jining remained unchanged. Among the 9 HAdV-C sequences from Jining, 4 were identified as HAdV-104 and 5 as HAdV-108. The RGD motif in Penton base protein and receptor-binding sites in Fiber protein remained unchanged in all 9 HAdV-C sequences.

CONCLUSIONS

From February 2023 to July 2024, HAdV in Jining City primarily circulated among younger age groups in influenza-like illness cases, with no apparent seasonal pattern. Enhanced surveillance of HAdV and accelerated development and marketing of HAdV vaccines are necessary.