Diverse genotypes of human enteric and non-enteric adenoviruses circulating in children hospitalized with acute gastroenteritis in Thailand, from 2018 to 2021

Abstract

Human adenovirus (HAdV) is a common viral pathogen that causes diarrhea in children worldwide. The aim of this study was to investigate the prevalence and genotype diversity of HAdV strains circulating in children admitted to the hospitals with acute gastroenteritis (AGE) in Chiang Mai, Thailand, from 2018 to 2021. A total of 1,790 stool samples were screened for HAdV by PCR method, and 80 (4.5%) were positive for HAdV. Of these, children under 5 years of age accounted for 90.0% of HAdV-positive cases with the highest infection rate at the age group of 48-60 months old. The infection rate was not significantly different between boys and girls. The HAdV infection was detected sporadically throughout the year without a discrete seasonal pattern. Five species of both enteric and non-enteric HAdVs (A, B, C, E, and F) with 10 different genotypes, including HAdV-F41 (25.0%), HAdV-B3 (17.5%), HAdV-F40 (16.3%), HAdV-C1 (15.0%), HAdV-C5 (7.5%), HAdV-C2 (6.3%), HAdV-B7 (5.0%), HAdV-A12 (3.8%), HAdV-E4 (2.5%), and HAdV-B11 (1.3%), were detected in this study. In conclusion, our study reported the prevalence and seasonality of HAdV infection with a wide variety of HAdV genotypes circulating in children hospitalized with AGE during a period of 2018-2021 in Chiang Mai, Thailand. IMPORTANCE In the present study, the prevalence of human adenovirus (HAdV) infection in children with acute gastroenteritis (AGE) in Chiang Mai, Thailand, from 2018 to 2021 was detected at 4.5%. Diverse species and genotypes of HAdVs (HAdV-A12, HAdV-B3, HAdV-B7, HAdV-B11, HAdV-C1, HAdV-C2, HAdV-C5, HAdV-E4, HAdV-F40, and HAdV-F41) had been identified. The highest infection rate was found in children aged 48-60 months old. The HAdV infection was detected sporadically throughout the year. These findings imply that a wide variety of HAdV genotypes circulate in pediatric patients with AGE in Chiang Mai, Thailand.

Keywords: Thailand; adenovirus; children; gastroenteritis.

Fig 1

Monthly distribution of human adenovirus infection in children with acute gastroenteritis during 2018–2021. The left axis indicates the number of cases, and the right axis indicates the percentage of positive cases (%). The length of the blue bar indicates the number of cases tested, the length of the orange bar indicates the number of HAdV-positive cases, and the dot color indicates the percentage of HAdV-positive cases.

Fig 2

Distribution of human adenovirus genotypes in patients with acute gastroenteritis during 2018–2021. (a) Bar chart indicates the number of HAdV genotypes; the x-axis indicates the HAdV genotypes detected, and the y-axis indicates the number of cases. (b) Pie charts indicate the percentage of HAdV genotypes detected in each year during the study period of 2018–2021.

Fig 3

Phylogenetic analysis of partial nucleotide sequences (443 bp) of the hexon gene. The phylogenetic tree of human adenovirus strains detected in Thailand during 2018–2021 (80 sequences) and reference strains available in the Genbank database was constructed by MEGA X software with GTR + G + I model and supported by 1,000 bootstraps. The triangle indicates the HAdV strains detected in this study, and HAdVs with different genotypes are indicated by different colors. The reference strains of each HAdV genotype are indicated by strain name and accession number.