A Survey of Recent Adenoviral Respiratory Pathogens in Hong Kong Reveals Emergent and Recombinant Human Adenovirus Type 4 (HAdV-E4) Circulating in Civilian Populations

Viruses. 2019 Jan 31;11(2):129. doi: 10.3390/v11020129.


Human adenovirus type 4 (HAdV-E4), which is intriguingly limited to military populations, causes acute respiratory disease with demonstrated morbidity and mortality implications. This respiratory pathogen contains genome identity with chimpanzee adenoviruses, indicating zoonotic origins. A signature of these "old" HAdV-E4 is the absence of a critical replication motif, NF-I, which is found in all HAdV respiratory pathogens and most HAdVs. However, our recent survey of flu-like disease in children in Hong Kong reveals that the emergent HAdV-E4 pathogens circulating in civilian populations contain NF-I, indicating recombination and reflecting host-adaptation that enables the "new" HAdV-E4 to replicate more efficiently in human cells and foretells more potential HAdV-E4 outbreaks in immune-naïve civilian populations. Special attention should be paid by clinicians to this emergent and recombinant HAdV-E4 circulating in civilian populations.

Keywords: civilian populations; evolution; genome recombination; host adaptation; human adenovirus type 4; respiratory pathogens; zoonosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptation, Biological / genetics
  • Adenovirus Infections, Human / epidemiology*
  • Adenoviruses, Human / genetics*
  • Adenoviruses, Human / pathogenicity
  • Child
  • Communicable Diseases, Emerging / epidemiology
  • Communicable Diseases, Emerging / virology*
  • DNA, Viral / genetics
  • Evolution, Molecular
  • Genome, Viral
  • Hong Kong / epidemiology
  • Hospitals / statistics & numerical data
  • Humans
  • Inpatients
  • Nasopharynx / virology
  • Outpatients
  • Phylogeny
  • Recombination, Genetic*
  • Respiratory Tract Infections / epidemiology
  • Respiratory Tract Infections / virology*


  • DNA, Viral