Epidemiology of Human Adenoviruses: A 20-Year Retrospective Observational Study in Hospitalized Patients in Bern, Switzerland

Akello, Joyce Odeke; Kamgang, Richard; Barbani, Maria Teresa; Suter-Riniker, Franziska; Leib, Stephen L; Ramette, Alban

Our study has a number of limitations. First, our reported trends likely underestimate the true burden of HAdV infections in both the hospitalized patients and in the community, as samples sent for laboratory diagnostic testing to the IFIK rely on request by physicians, when an adenovirus infection is suspected. Second, samples were tested using different diagnostic methods for HAdV and some methods are known to be less sensitive for HAdV detection than others. 46 Therefore, there is a chance that this could have also affected the results of our study. Third, some of the clinical information was missing, hence restricting interpretation of trends in HAdV clinical presentation associated with circulating genotypes. In addition, clinical information was obtained from electronic clinical records provided to the IFIK diagnostic department and could not be improved in most of the cases. Fourth, several HAdV positive samples could not be genotyped due to unavailability/lack of sample material. Although the missing information was not systematic for a particular age group, sample type or year, the unavailable information might have biased our results and therefore, the reported HAdV genotypes might not be fully representative of circulating HAdV genotypes in a given year. In addition, a complete quantitative description of the main genotype (s) causing an increase in HAdV infection every 4 years among young children could not be reached due to this lack of samples.