Abstract:
Enteric viruses have been recognized as the most important etiologic agents of
gastroenteritis worldwide in young children. The major enteropathogenic viruses include:
rotavirus, norovirus, adenovirus, astrovirus and sapovirus. Worldwide, rotavirus is
considered to cause a greater proportion of diarrhoea in children. Studies have
investigated the prevalence and epidemiology of these viruses in many countries,
however, mostly in hospitalized children. There is limited data available of viruses
causing diarrhea amongst outpatient cases including the circulating aetiologies,
prevalence and seasonality. The aim of this study was therefore to determinethe
prevalence of these five most important diarrhoeal viruses among children below14
years of age who visited the outpatient clinic atLwakMissionHospitalin Asembo with
mild to severe symptoms of diarrhoea.This was a sub-study within a major Morbidity
study SSC No. 932: Active Population-based Study of Infectious Disease Syndromes in
Western Kenya and Nairobi. A total of 206 stool specimens collected from children
below the age of fourteen years who visited the outpatient clinic in Asembo with
diarrhoea, between January 2007 and June 2010 were screened for rotaviruses,
noroviruses, adenoviruses, astroviruses and sapoviruses. Enzyme immunoassay
technique was used to test for the presence of rotavirus and adenovirus, while reverse
transcriptase multiplex polymerase chain reaction (RT-PCR) assay was used for
norovirus, astrovirus and sapovirus detection. At least one viral agent was detected in
26.7% (55/206) of the children. Rotavirus was the most prevalent with 13.6% (28/206),
whereas norovirus was detected in 6.3% (13/206), adenovirus in 4.9% (10/206),
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astrovirus in 2.9% (6/206) and sapovirus in 1.5% (3/206). Mixed infection (co-infection
of viruses) was found in 9.1% (5/55) of the positive samples, with the majority of coinfections
attributable to rotavirus dual infections.In most cases the viruses were
detected in children aged 13-24 months (≤ 2 years) as the average age of children
infected with these agents was less than five years. Vomiting and fever were the most
common clinical features detected in these children especially amongst those who had
rotavirus and norovirus infections. These findings suggest that at least five enteric
viruses are potentially important agents of diarrhoeain this rural site in western Kenya.
Defining clinical and epidemiologic characteristics predictive of viral etiology may have
implications for the management of diarrhea in children in Kenya and similar settings.