Diversity of viruses associated with acute gastroenteritis in children hospitalized with diarrhea in Ho Chi Minh City, Vietnam

Abstract

A molecular epidemiological study on common diarrheal viruses was conducted in Ho Chi Minh City, Vietnam between October 2002 and September 2003. Fecal samples were collected from 1,010 hospitalized children with acute gastroenteritis. Those samples were screened for groups A, B, and C rotavirus, adenovirus, genogroups I and II norovirus (NoV), sapovirus (SaV), and human astrovirus (HAstV) by RT-multiplex PCR, and the positive specimens were characterized further by ELISA, nested PCR, or sequencing. Among the diarrheal viruses detected, group A rotavirus was the most common, with a proportion of 67.4%, whereas NoV GII, adenovirus, SaV, and HAstV were also found in 5.5, 3.2, 0.8, and 0.6%, respectively. It is noteworthy that the group C rotavirus was first reported in Vietnam, with a proportion of 0.5% in this study. Fifty-six of 1,010 (5.5%) samples were found positive with more than one viral agent, in which 25 samples contained both group A rotavirus and NoV GII. Group A rotavirus could be identified throughout year with the peaks in both the dry and rainy season, whereas other viruses prevailed mainly in the rainy season. G-typing for the group A rotavirus showed that genotype 1 was still the most prevailing (33.0%), but interestingly, serotype 9 was emergent and became the third most common rotavirus G-type in these samples (13.7%). The four most common G-P combinations globally, G1P[8], G2P[4], G3P[8], and G4P[8] were found in 46.8% of rotavirus-positive samples, and it is of interest that one unusual rotavirus G9P[19] strain was first detected in Vietnam. The majority of NoV strains belonged to GII/4, and SaV strains mainly clustered with the Manchester strain (GI/1). Twenty-seven out of 32 adenovirus strains were identified as serotype 41. All HAstVs belonged to genotype 1. The results indicated clearly the impact of viral agents causing gastroenteritis and the importance of vaccination against diarrhea in Vietnam.

Acute Infantile Gastroenteritis Associated with Human Enteric Viruses in Tunisia

“…The 26 HAstV-positive samples, for example, were isolated mainly from children with mixed infections (17 samples) and from nonhospitalized children (17 samples). These results remain in accordance with those of several other studies showing that this virus causes asymptomatic infections or mild forms of gastroenteritis which are treated at home (5,25,28). More surprising was the result regarding the incidence of Aichi virus monoinfections.…”

“…Studies in Chile, China, France, and Australia reported NoVs as the etiologic agent in 8 to 15% of children with moderate to severe gastroenteritis who either attended the outpatient clinic or were hospitalized (4,17,30). Other studies in Finland (31) and Germany (28) and recently in Vietnam (25) found NoV in 20% to 55% of stool samples, whereas the incidence of RV was found in 31% to 67% of stool samples. Moreover, by coupling fecal detection with serological testing, Parashar et al (34) found in Peruvian children under 5 years old an incidence of NoVs that reached 55%, a rate comparable to that seen with of RVs.…”

“…Although the role of these viruses in outbreaks of gastroenteritis in industrialized countries has been established (7,29), little is known about their contribution to outbreaks in developing countries and few data are currently available (25). In Tunisia, a middle-income Mediterranean country, earlier studies showed the contribution of RVs (8,38) and more recently that of HAstVs and HAdVs (12) in cases of childhood diarrhea.…”

Epidemiology and clinical features of gastroenteritis in hospitalised children: prospective survey during a 2-year period in a Parisian hospital, France

“…A number of previous studies found lower levels of disease severity in norovirus than in rotavirus gastroenteritis, and most of these were carried out in developed countries [7,[43][44][45][46][47]. In contrast, other studies found no significant differences between the severity of rotavirus and norovirus infections [48][49][50][51]. One such study was conducted by us in Tunisia, and we attributed the severity of the norovirus infection to a lack of medical care at home and the delay to hospitalization for children infected with norovirus.…”

Prevalência e diversidade molecular de adenovírus em crianças com gastroenterite aguda grave, em Belém, estado do Pará, antes e após a introdução da vacina contra rotavírus no Brasil

“…Esse resultado está de acordo com o observado em outros estudos conduzidos em vários países, os quais demonstram o predomínio do tipo 41 em relação ao 40 36,37,38,39 . O tipo 41 esteve presente em 32 de 37 amostras de HAdV de um estudo conduzido no Vietnã 40 ; além disso, representou 94,5% do total de amostras positivas na Tunísia 23 . Na Austrália, a frequência do tipo 41 aumentou bastante no período de 1981 a 1992, passando de 25% em 1981 até atingir 100% em 1992 41 .…”