Human adenoviruses (HAdV) are genetically diverse and can infect a number of tissues with severities varied from mild to fatal. HAdV types 3,4,7,11,14,21, and 55 were associated with acute respiratory illnesses outbreaks in the United States and in other countries. The risk of outbreaks can be effectively controlled by HAdV vaccination or mitigated by screening and preventive measures. During the influenza season 2018-2019, the DoD Global Respiratory Pathogen Surveillance Program (DoDGRS) received 24 300 respiratory specimens. HAdV samples that produced positive cytopathic effects in viral cultivation were subjected to next-generation sequencing for genome sequence assembly, genome typing, whole genome phylogeny, and sequence comparative analyses. A variety of HAdV types were identified in this study, including HAdV types 1-7, 14, 55, and 56. HAdV types 4, 7, and 14 were found in clustered cases in Colorado, Florida, New York, and South Carolina. Comparative sequence analyses of these isolates revealed the emergence of novel genetic mutations despite the stability of adenovirus genomes. Genomic surveillance of HAdV suggested possible undetected outbreaks and shed light on prevalence, genetic divergence, and viral evolution of HAdV. Continued surveillance will inform risk assessment and countermeasures.

Here, we report two complete genome sequences of human adenovirus 55 (HAdV-55) isolates, from a patient in Pennsylvania in 2006 and a U.S. military member in South Korea in 2019. The findings demonstrate the continued global transmission of HAdV-55 viruses in both military and civilian populations.

Human adenoviruses (HAdV) are genetically diverse and can infect a number of tissues with severities varied from mild to fatal. HAdV types 3, 4, 7, 11, 14, 21 and 55 were associated with acute respiratory illnesses (ARI) outbreaks in the US and in other countries. The risk of outbreaks can be effectively controlled by HAdV vaccination or mitigated by screening and preventive measures. During the influenza season 2018 – 2019, the DoD Global Respiratory Pathogen Surveillance Program (DoDGRS) received 24,300 specimens. HAdV samples that produced positive cytopathic effects in viral cultivation were subjected to next-generation sequencing for genome sequence assembly, genome typing, whole genome phylogeny, and sequence comparative analyses. Variety of HAdV types were identified in this study, including HAdV types 1 – 7, 14, 55 and 56. HAdV types 4, 7 and 14 were found in clustered cases in Colorado, Florida, New York, and South Carolina. Comparative sequence analyses of these isolates revealed the emergence of novel genetic mutations despite the stability of adenovirus genomes. Genomic surveillance of HAdV related to possible outbreaks, shed light on prevalence, genetic divergence, and viral evolution of human adenoviruses. Continued surveillance will inform risk assessment and countermeasures.

Background Human adenoviruses (family Adenoviridae, genus Mastadenovirus) (HAdV) species B, C and E cause acute respiratory illnesses (ARI). In particular, respiratory HAdV types 3, 4, 7, 11, 14, 21 and 55 were associated with ARI outbreaks in the US and in other countries. The risk of outbreaks can be effectively controlled by implementation of the live HAdV types 4 and 7 vaccines or mitigated by screening and preventive measures. Methods During the influenza season 2018 – 2019, the DoD Global Respiratory Pathogen Surveillance Program (DoDGRS) received 24,300 specimens from its surveillance network. In total, 322 (1.3%) respiratory specimens were positive for HAdV in molecular assays. HAdV samples that produced positive cytopathic effects (CPE) in subsequent viral cultivation were subjected to next-gen sequencing (NGS) for genome sequence assembly, HAdV genome typing, whole genome phylogeny, and sequence comparative analyses to identify sequence insertions, deletions and amino acid mutations. Results Out of 166 viral culture samples available for NGS, whole genome sequences were obtained for 161 isolates. A variety types of HAdV were identified, including HAdV-1 (N = 15), HAdV-2 (N = 26), HAdV-3 (N = 60), HAdV-4 (N = 13), HAdV-5 (N = 6), HAdV-6 (N = 3), HAdV-7 (N = 12), HAdV-14 (N = 10), HAdV-55 (N = 1), and HAdV-56 (N = 1). HAdV types 4, 7 and 14, which were reported causing ARI outbreaks in the US military and other congregate settings, were found in clustered cases in several US states. Comparative sequence analyses of these isolates revealed the emergence of novel genetic mutations despite the stability of adenovirus genomes. Conclusion Routine clinical respiratory pathogen diagnostics or molecular surveillance of respiratory diseases detect adenovirus without determination of HAdV type. Human adenoviruses are genetically diverse and can infect a number of tissues with severities varied from mild to fatal. Enhanced genomic surveillance of HAdV in the US and worldwide will shed light on prevalence, genetic divergence, and viral evolution of human adenoviruses and inform timely risk assessment and countermeasures. Disclosures All Authors: No reported disclosures.