MICROBIOLOGY

• Human adenovirus (HAdV) is a non-enveloped double-stranded DNA virus.
  
  • There are 7 human species (A-G) and over 85 genotypes. Genetic heterogeneity contributes to diverse tropism and results in many organs and tissues infection.[7]
    • Human Adenovirus Working Group coordinates and standardizes assigning names to candidate novel HAdV, accessed 1/30/2023 at http://hadvwg.gmu.edu/.
  • Recent outbreaks are linked to types 4, 7, and 14.[9] The 2021-22 Alabama case series of pediatric acute hepatitis reported 9 cases with confirmed adenovirus infection but did not identify a single outbreak strain.[4]
• Easily transmitted via aerosolized droplet, fecal-oral, waterborne, fomites and instruments.[10]
• Persists in the environment may remain infectious at room temperature for up to 3 wks. Higher prevalence rates occur in regions with limited sanitation, and there is no seasonality to infection.[1]
• Stable at low pH and resistant to gastric and biliary secretions.
  • Replicates to high viral load in the gut and can be asymptomatically shed. HAdV can persist in intestinal lymphocytes and reactivate during severe immunosuppression.[15]
  • Detection in stool often precedes detection in blood.[13] Few serotypes, i.e., subgroup C, can induce latent infection in lymphoepithelial tissue.[2]