Page 54 - 15Diarrhoeaandvomiting

Diagnosis

the condition following hospitalisation were examined. Gastroenteritis was considered to
be healthcare associated if symptoms developed 48 hours or more following admission. The
study included a total of 243 subjects (87% of eligible subjects) who had clinical data and a
stool specimen collected during the 5 month study period, and 37% (91/243) of these cases
were judged to be healthcare associated while the rest were diagnosed to have community-
acquired infection. Rotavirus was detected in altogether 29% of cases (71/243). The proportion of
community-acquired cases testing positive for rotavirus was 36% (54/152), while for healthcare-
associated cases the proportion was 19% (17/91). [EL = 3]
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In the sixth study, conducted in East Anglia, England, stool samples collected during three
consecutive winter seasons (2000–2003) were tested for the presence of viral pathogens. The
sample population comprised 685 children younger than 6 years with symptoms of gastroenteritis:
223 children presenting to a general practitioner (part of a structured surveillance study evaluating
burden of disease), 203 children referred by various general practices in the community to the
hospital, and 259 children admitted to the hospital as inpatients or attending the accident and
emergency department. A viral agent was detected in 53.4% of samples (366/685). A significantly
greater number of children from the structured surveillance study group had a viral pathogen
detected in their stool specimen compared with the community cohort (68.6% versus 51.2%;
P < 0.05) or the hospital cohort (68.6% versus 42.1%; P < 0.05). The proportion of children from
the community with a viral agent detected was also significantly higher compared with children
in the hospital cohort (51.2% versus 42.1%; P < 0.05). Rotavirus was the most common pathogen
isolated in each of the three cohorts: 40.4% in the structured surveillance study, 24.6% in the
community cohort and 17.8% in the hospital cohort. The second most common viral pathogen
isolated was norovirus in the surveillance study group (9.9%) and the hospital cohort group
(9.7%), while in the community cohort group it was enteric adenovirus (8.9%). Multiple viral
pathogens were detected in 8% of the samples and most of these (72.7%) involved rotavirus in
combination with other viruses. [EL = 3]
As part of a prospective, multicentre study on the incidence of rotavirus in Europe, 1010 stool
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samples were examined from children younger than 5 years who presented with gastroenteritis
to a regional health service in the UK in the winter of 2004–2005. The results were reported
in relation to the clinical setting in which they were seen: primary care (general practitioners
and/or paediatricians), emergency department and hospital admission. The overall percentage
of children with rotavirus-positive gastroenteritis was estimated to be 35.9%, with the incidence
being almost the same for the two groups of children seen in the emergency department and
hospital (60.0% and 60.7%, respectively). In a primary care setting, rotavirus was isolated in
31.9% of the samples. [EL = 3]
The last study was a population-based study undertaken to evaluate the incidence and aetiology
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of infectious intestinal disease in both adults and children presenting to general practitioners and
in the community, and to establish how many of them are reported to the national laboratory-
based surveillance. The study cohort included a population of 459 975 patients registered with
70 general practices in England, and this selected sample of population was representative
of all the general practices nationally with respect to geographical location, urban and rural
characteristics, and social deprivation index. To calculate incidence in the community, 200 people
were randomly recruited from each general practice out of which 9776 people (an average of
140 people from each general practice) agreed to participate. These people were asked to return
weekly postcards for 6 months declaring the absence of symptoms, and those with symptoms
were asked to send a stool specimen to a public health laboratory. Eighty-two percent of the
participants returned 22 or more of the 26 weekly postcards. For the general practice incidence
data, all cases of infectious intestinal disease presenting to a general practitioner were eligible
for inclusion irrespective of their age. The practices were randomly allocated to two arms: in the
first arm, all patients (34 general practices) were asked to send stool specimens to a public health
laboratory, while in the second arm (36 general practices), stool testing was conducted locally
and information sought from the national surveillance database on those with a positive stool
specimen. This step was taken to evaluate the completeness of the reporting system.
In the community, 781 cases were ascertained for infectious intestinal disease, with an incidence
of 19.4 per 100 person-years (95% CI 18.1 to 20.8), while 8770 people presented to their general
practice giving an incidence of 3.3 per 100 person-years (95% CI 2.94 to 3.75). The ratio of

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