Adenovirus Genotypes Associated With Severe Acute Respiratory Infections Outbreak in Children, in Antioquia,...

Human Adenovirus (HAdV) is a common cause of acute respiratory infections, typically mild in healthy individuals. However, in late 2022, an outbreak of severe acute respiratory infection caused by HAdV emerged among children in Colombia and other countries.

We described an HAdV outbreak between February 2022 and April 2023. Children with severe acute respiratory infection and HAdV infection confirmed by polymerase chain reaction were included in 4 institutions in Antioquia, Colombia. Our study investigated the clinical manifestations and circulating HAdV genotypes before, during and after this HAdV outbreak.

A total of 133 HAdV cases were analyzed, 37 (27.8%) cases were classified as the preoutbreak group, 88 (66.1%) as the outbreak and 8 (6.0%) as the postoutbreak group. Predominant symptoms were fever (87.0%), rhinorrhea (57.1%) and dyspnea (36.8%). The need for intensive care unit admission and supplemental oxygen increased during the outbreak and peaked in the postoutbreak period. Phylogenetic analysis revealed that 71.4% (10/14) of preoutbreak sequences belonged to genotype HAdV-C89, while during the outbreak, 75.6% (28/37) were HAdV-B3. Clinical symptoms did not significantly differ between HAdV-C89 and HAdV-B3 infections, but children infected with HAdV-B3 were significantly older.

This study highlights the shifting dynamics of HAdV genotypes in children and their epidemiologic impact. The emergence of HAdV-B3 in the post-COVID-19 period contributed to a severe acute respiratory infection outbreak, emphasizing the need for ongoing surveillance.