Adenovirus infections in Bordeaux University Hospital 2008-2010: clinical and virological features.

Background: Transversal epidemiological data on adenovirus infections in a hospital setting, including both immuno-competent and transplanted patients, are limited and rarely contain the application of molecular virology.

Objectives: To describe the clinical characteristics and molecular epidemiology of adenovirus infections in Bordeaux University Hospital from 2008 to 2010 (clinical data, viral load and adenovirus species distribution).

Study Design: Adenovirus DNA quantification (qPCR) and typing (sequencing of hexon and protein VI genes and protein VI polymerase chain reaction (PCR) product analysis) were applied retrospectively to 215 clinical samples from 105 adenovirus-infected patients (2008-2010, Bordeaux University Hospital). Clinical data were recovered and analysed for 73 children and 25 adults.

Results: Viral loads were measured in stools, upper and lower respiratory fluids, blood, urine and digestive tract biopsies; the highest values were observed in stools and respiratory samples. Stool viral loads were comparable whatever the immune status. Adenovirus was typed in 57 patients: species Human adenovirus (HAdV) C dominated (n=36), followed by B (n=15), F (n=5) and D (n=1). We could demonstrate no association between HAdV species and load or clinical severity (observed in most patients). In the immuno-compromised, in contrast to immuno-competent patients, adenovirus infections presented no seasonal variation. Co-infections were frequent: mostly bacterial in immuno-competent children (33%) and viral in immuno-compromised people (34%).

Conclusions: The species HAdV C dominates the local ecology, in both respiratory and digestive tract infections, independently of the patient's immune status. Adenovirus infections, often associated with co-infection of bacterial or viral agents, frequently lead to severe clinical consequences in hospital patients.