Pathogens causing community gastroenteritis in Australia.

BACKGROUND AND AIM: Many individuals with gastrointestinal symptoms do not seek medical attention and so there is little known about the pathogens involved in most cases of community gastroenteritis. We aimed to identify the pathogens responsible for community gastroenteritis and to examine the associated symptoms.
METHODS: In a prospective study of 2811 subjects over 15 months, fecal pathogens were examined following highly credible gastroenteritis (HCG) events. The population consisted of family units of at least two children (< or =15 years-old) and two adults each. Fecal samples were tested for a range of bacterial, viral and protozoal pathogens. Gastroenteric episode duration and symptoms such as vomiting, nausea and diarrhea were measured.
RESULTS: One or more pathogens were identified in 198 of a total 791 specimens collected. Pathogens detected most often were Norovirus virus (10.7%), pathogenic E. coli (6.7%), Campylobacter spp. (3.0%) and Giardia sp. (2.5%). Children were more prone than adults to all the pathogens tested, except E. coli. Children infected with Campylobacter were 8.3 times more likely (95% CI: 2.7-25.4) to have a longer duration of diarrhea than children with Norovirus (P < 0.001). Similarly, children infected with E. coli had increased persistence of diarrhea compared to Norovirus (OR = 3.5; 95% CI: 1.3-9.5; P = 0.02). Infection with Norovirus in children meant greater persistence of vomiting symptoms than infection with Campylobacter (P = 0.005), E. coli (P = 0.03), or if no pathogen was identified (P = 0.004). Adults usually vomited for fewer days than children while duration of diarrhea was similar to children.
CONCLUSIONS: Many of the pathogens responsible for cases of gastroenteritis in the Australian community are likely to go undetected by current surveillance systems and routine clinical practice.