[Molecular epidemiology of human adenovirus diarrhea among infants and young children in Lanzhou from July 2005 to June 2008].

OBJECTIVE: Gastroenteritis is a major cause of childhood morbidity and mortality worldwide. Adenovirus AdV is recognized to be one of the most important pathogens associated with severe dehydrating gastroenteritis. Studies reported elsewhere have shown that about 8%-10% of cases with infantile diarrhea are caused by AdV and in some areas AdV diarrhea even occurred in the form of outbreaks. Studies have confirmed that AdV infections are also very common in infants and young children in China. This study aimed to investigate the molecular epidemiologic characteristics of human adenovirus diarrhea among infants and children with acute diarrhea in Lanzhou, Gansu province, China.

METHOD: Stool specimen and case information were collected from both outpatients and inpatients with acute diarrhea in Lanzhou. Polymerase chain reaction was used to detect AdV in stool specimens. The subjects included 709 urban children and 180 rural children, their age ranged from 19 d to 60 months.

RESULT: Of the 889 cases, 43 (4.8%) were found positive for AdV. AdV was detected in 14 of 257 (5.4%) cases seen from July 2005 to June 2006, in 4 of 286 cases (1.4%) seen from July 2006 to June 2007. During the period of July 2007 to June 2008, adenovirus was detected in 346 specimens, the positive rate was 7.2% (25/346). AdV detection rates of the three-year period were significantly different. The major AdV subtypes detected were adenovirus (subgenus F) Ad40, Ad41 with a positive rate of 3.8% (34/889), followed by non-enteric adenovirus (Ad12, Ad18, Ad31, Ad2, Ad5, Ad6, Ad7) with a positive rate of 1.0% (9/889) in Lanzhou during the 3 years. Most of the AdV-positive specimens showed Ad41 group F (67.4%, 29/43) as the major epidemic strains, and Ade infection mainly occurred in children under one year of age and no seasonal cluster was found.

CONCLUSION: Adenovirus was one of the major etiological agent of viral diarrhea among infants and children in Lanzhou between 2005 and 2008. Ad41 was the prodomiment serotype.