Viruses causing gastroenteritis in children thrive in stools of asymptomatic carriers

The stools of asymptomatic patients carry the most common viruses that cause gastroenteritis in children and serve as a potential reservoir for acute gastroenteritis (AGE), a study has shown.

A team of investigators collected 999 stool samples from children under 16 years of age from September 2009 to August 2011 at Tampere University Hospital, Finland, to examine the prevalence and the genetic variations of sapovirus, norovirus, and rotavirus.

A total of 442 children (44 percent) had symptoms of AGE, and 557 (56 percent) had acute respiratory tract infection (ARTI) only. The investigators examined samples for sapovirus, norovirus, and rotavirus using reverse transcription-polymerase chain reaction and sequenced the positive amplicons.

Fifty-four percent of patients with AGE and 14 percent of those with ARTI tested positive. All viruses were more frequently found in AGE than in ARTI patients: norovirus (25 percent vs 7.2 percent), rotavirus (24 percent vs 6.1 percent), and sapovirus (5.2 percent vs 1.4 percent). Of note, cases in ARTI patients were detected most frequently during the first 2 years of life.

In both groups, the most detected pathogen was norovirus, with genogroup GII covering ≥97 percent of norovirus strains. Sapovirus was found mostly in children <18 months old, with no predominating genotype. Finally, rotavirus was commonly detected following recent rotavirus vaccination, with 18 percent and 88 percent of the strains being vaccine-derived in AGE and ARTI groups, respectively.

“Sapovirus, norovirus, and rotavirus are major causes of AGE globally,” the investigators noted.