Overview of rotavirus infections in Korea

Rotavirus is the most common cause of acute watery diarrhea in young Korean children. Rotavirus vaccine will soon be available, and information is urgently required about the serotype distribution of recent epidemics and clinical characteristics of rotavirus infection in Korean children before the implementation of a vaccination program against rotavirus. We reviewed published studies of the past 20 years, carried out on Korean children with rotavirus gastroenteritis. Rotavirus was estimated to be responsible for 46% of 4668 hospitalized Korean children with acute gastroenteritis. Rotavirus gastroenteritis was most prevalent among children aged 6-24 months, which accounted for 84% of all cases. Asymptomatic rotavirus infection was common. Rotavirus was one of the most commonly identified enteric pathogens in nosocomial diarrhea. Vomiting, respiratory symptoms and fever were prominent symptoms in rotavirus gastroenteritis. Transient elevation of liver enzymes, pulmonic infiltration and rarely afebrile convulsion were also observed. The epidemic peak, which occurred in November of the last 15 years, has been moving toward late winter and early spring in recent years. No apparent cause has been found to explain this alteration of peak seasonality. All serotyping studies in Korea for the past 10 years until 1997 revealed that G1 was most prevalent (45-81%). Interestingly, the predominant G serotype of the recent outbreaks in 1998 and 1999 was not G1 but G4. Approximately 95% of rotavirus isolates in recent outbreaks belonged to serotype G1, 2, 3 or 4.     

Acute gastroenteritis in children attending day-care centres with special reference to rotavirus infections. II. Clinical manifestations

In a prospective study of a cohort of 214 children (aged 6 months-7 years) attending day-care centres, a total of 197 episodes of acute gastroenteritis (GE) occurred in 109 children (i.e. 51% of the participants) during a 12-month observation period. Rotavirus, pathogenic bacteria and Giardia lamblia caused GE in 24%, 6% and 2% of the cases, respectively. The aetiology of the remaining 68% was not discovered. Generally, the symptoms of GE were light and only two episodes led to hospitalization. Thirty-two rotavirus infections were asymptomatic. Two rotavirus GE reinfections occurred. They showed less severe symptoms than the primary infections. The older children (greater than 1.5 years) with rotavirus GE had lighter symptoms than the younger ones (less than or equal to 1.5 years). Compared with children with non-rotavirus GE, those with rotavirus GE showed the following clinical features: (1) Age between 6 months and 2 years. (2) Occurrence of rotavirus GE almost exclusively during the rotavirus season, i.e. January to April (winter). (3) High frequency of vomiting, the onset of which often preceded that of diarrhoea. However, these signs did not form a safe basis for the clinical diagnosis of rotavirus GE. One or more upper respiratory manifestations (URM) were observed in 39% of the children with rotavirus GE and in 36% of those with non-rotavirus GE. The occurrence of URM was age-related being highest in children less than 2 years. Consequently, the existence of a rotavirus syndrome is questioned. It is argued that URM in children with rotavirus GE may be due to a co-infection of the upper respiratory tract by a different micro-organism.     

多重感染致儿童急性腹泻病的多中心临床研究

目的 观察急性腹泻患儿中单一感染与混合感染的发病率,比较单一和多个病原体感染患儿的临床表现.方法 采用回顾性研究方法,选择年龄1个月～14岁诊断急性腹泻病的患儿4728例作为观察对象.单一感染组和混合感染组患儿均进行大便常见病原体检测,包括轮状病毒(rotavirus,RV)、肠道腺病毒(enteric adenovirus,EAdV)、诺如病毒(norovirus,NV)抗原以及常见肠道致病菌的培养、分离鉴定.同时观察患儿病情的严重程度,包括腹泻持续时间和频率,发热、呕吐持续时间以及脱水的程度.结果 4 728例患儿中有一种及一种以上病原体感染的有3 595例(76.0％),实验室检测未发现病原体感染的患儿有1 133例(24.0％).其中RV感染有1 889例(40.0％),EAdV有412例(8.7％),NV感染有309例(6.5％),大肠埃希菌(VTEC) 274例(5.8％),沙门菌属276例(5.8％),肺炎克雷伯菌感染123例(2.6％),志贺菌78例(1.6％),金黄色葡萄球菌70例(1.5％)和产气荚膜杆菌126例(2.7％).其中1370例(29.0％)腹泻患儿存在混合感染,以RV合并NV感染150例(3.2％)及RV与产气荚膜菌混合感染127例(2.7％)为最常见.混合感染所致的儿童急性腹泻较单一感染临床表现更加严重,差异有统计学意义(P＜0.05).结论 轮状病毒仍是儿童急性腹泻最常见的病原体,其次为NV、EAdV、沙门菌属及VTEC.混合感染中轮状病毒合并诺如病毒感染最常见.在病毒与细菌混合感染时,VTEC与各类病毒合并感染发生率最高.多种病毒感染与单一病毒感染腹泻患儿比较,呕吐持续时间和脱水程度较严重,而发热及腹泻持续时间、腹泻频率则无明显差异.病毒合并细菌感染与单一病毒感染和单一细菌感染腹泻患儿的临床表现比较,混合感染患儿发热、呕吐及腹泻持续时间长,腹泻、脱水程度都更加严重.     

Estimates of economic burden of providing inpatient care in childhood rotavirus gastroenteritis from Malaysia

AIM: To estimate the cost of an episode of inpatient care and the economic burden of hospitalisation for childhood rotavirus gastroenteritis (GE) in Malaysia. METHODS: A 12-month prospective, hospital-based study on children less than 14 years of age with rotavirus GE, admitted to University of Malaya Medical Centre, Kuala Lumpur, was conducted in 2002. Data on human resource expenditure, costs of investigations, treatment and consumables were collected. Published estimates on rotavirus disease incidence in Malaysia were searched. Economic burden of hospital care for rotavirus GE in Malaysia was estimated by multiplying the cost of each episode of hospital admission for rotavirus GE with national rotavirus incidence in Malaysia. RESULTS: In 2002, the per capita health expenditure by Malaysian Government was US$71.47. Rotavirus was positive in 85 (22%) of the 393 patients with acute GE admitted during the study period. The median cost of providing inpatient care for an episode of rotavirus GE was US$211.91 (range US$68.50-880.60). The estimated average cases of children hospitalised for rotavirus GE in Malaysia (1999-2000) was 8571 annually. The financial burden of providing inpatient care for rotavirus GE in Malaysian children was estimated to be US$1.8 million (range US$0.6 million-7.5 million) annually. CONCLUSION: The cost of providing inpatient care for childhood rotavirus GE in Malaysia was estimated to be US$1.8 million annually. The financial burden of rotavirus disease would be higher if cost of outpatient visits, non-medical and societal costs are included.     

Astrovirus,adenovirus, and rotavirus in hospitalized children: prevalence and association with gastroenteritis

BACKGROUND: Agents of viral gastroenteritis such as astrovirus, rotavirus, and adenovirus are common pediatric pathogens accounting for many physician visits, hospital admissions, and nosocomial infections. Previous hospital-based prevalence studies have examined mainly symptomatic children. PURPOSE: To evaluate the prevalence of astrovirus, rotavirus, and adenovirus infections among hospitalized children less than 6 years of age, regardless of symptoms, and determine association with gastroenteritis. METHODS: From September 1998 to June 2000, stool specimens were collected twice weekly from children less than five years of age admitted to two wards in a tertiary-care children's hospital. A total of 480 samples were obtained from 309 hospitalizations. Stools were examined using antibody-based ELISA for astrovirus, rotavirus, and adenovirus. Clinical data was abstracted from patient records. RESULTS: Twenty one percent of the children had gastroenteritis symptoms at some point during their hospitalizations (43% were hospital acquired). Astrovirus was detected in 5.2% of all children compared to 6.8% with rotavirus and 0.8% with adenovirus serotypes 40 or 41. Nosocomial acquisition was common. Seventy five percent of astrovirus infections and 90% rotavirus infections were symptomatic. Astrovirus infections were significantly more likely to occur in younger infants and in children with compromised immunity. Rotavirus infections were significantly more likely to cause dehydration. In a three-year passive surveillance of gastroenteritis at the hospital, astrovirus and rotavirus infections peaked simultaneously in winter months. CONCLUSIONS: Rotavirus and astrovirus are common symptomatic infections on pediatric wards and contribute greatly to inpatient morbidity. Adenoviruses played a limited role in gastroenteritis in hospitalized children in this study.     

Intestinal and serum immune response to a naturally acquired rotavirus gastroenteritis in children

Seventeen children (mean age: 2.0 years, range: 36 days-8 years) hospitalized with acute gastroenteritis were investigated. Thirteen children had a rotavirus infection while four did not. Rotavirus serum IgA as well as ScIg, i.e., antirotavirus immunoglobulin containing secretory component, increased rapidly after rotavirus infection. While rotavirus IgA persisted in serum for at least 6 months, rotavirus ScIg disappeared from serum in less than 4 months. Rotavirus IgG could be detected in serum during the early stage of the infection and was still high after 6 months. The patients with nonrotavirus acute gastroenteritis did not show any of the above-mentioned serological hallmarks of those with rotavirus infection. The amounts of rotavirus ScIg found in serum about 1 week after the infection correlated to the amounts of rotavirus ScIg in duodenal fluid. Six months after the infection, rotavirus IgA was found in the feces of the majority of the patients while rotavirus ScIg could be detected only in one patient. The amounts of rotavirus IgA in sera and intestinal secretions showed identical patterns in the acute phase of the disease as well as after recovery. The same applied to rotavirus ScIg. These findings could be useful in future evaluations of vaccines and immunity against rotavirus infections.     

Hospital surveillance of rotavirus infection and nosocomial transmission of rotavirus disease among children in Guinea-Bissau

BACKGROUND: Vaccination against rotavirus is protective against severe disease. Surveillance of rotavirus infection in developing countries might direct vaccination policy more efficiently. METHODS: We implemented WHO's generic protocols for hospital-and community-based surveillance of rotavirus gastroenteritis. From April 2001 to May 2002, and from January 2003 to June 2003, we conducted hospital surveillance for rotavirus infection at the only pediatric ward in the capital of Guinea-Bissau. Children less than 5 years of age admitted with diarrhea or developing diarrhea during hospitalization were enrolled in the study. Rotavirus infection was detected in the feces samples using an ELISA assay. Rectal swabs were also obtained and its use was validated against stool specimen. RESULTS: During the surveillance period, 161 cases of rotavirus infection were registered. During the season, rotavirus accounted for 35% of all hospitalized diarrhea cases. The rate of nosocomial disease was 1.6 per 1000 child-days (95% confidence interval [CI] = 1.02-2.51) with high rates for children aged 12 to 23 months of age (rate: 3.09; 95% CI = 1.47-6.48). Most of the rotavirus cases (93%) were in children less than 2 years of age and only 10 children aged less than 3 months were infected. Fever (risk ratio (RR) 1.56; 95% CI = 1.16-2.10) and vomiting (RR 1.38; 95% CI = 1.11-1.73) were more common in patients with rotavirus than in patients with nonrotavirus diarrhea. The case-fatality was 8%. Results from stool samples and rectal swabs were concordant in 96% of the pairs. Rectal swabs increased the detection of rotavirus cases by 6% and deaths by 33% over stool sample results. CONCLUSION: Rotavirus infections were confined to a 4-month period each year. It is an important cause of childhood diarrhea with high case-fatality ratio in Guinea-Bissau. The use of rectal swab appeared to increase the detection rate of rotavirus infection and the case-fatality rate. The high rate of nosocomial infections in hospitalized children emphasizes the need for prevention of disease.     

Rotavirus gastroenteritis among children under five years of age in Izmir, Turkey

Little is known about the epidemiology of rotavirus infection in Turkey. The aim of the study was to determine the incidence and clinical significance of rotavirus gastroenteritis, in view of the potentially available prevention by rotavirus vaccination. The study also sought to determine possible risk factors for rotavirus gastroenteritis. Therefore, 920 children under five years of age with acute gastroenteritis admitted to three pediatric hospitals in Izmir were studied. Rotavirus was identified in 39.8% of the children. Most children with rotavirus gastroenteritis (80.7%) were younger than two years of age. Marked seasonality of rotavirus gastroenteritis was observed, with a peak incidence from January to March. A total of 91% of rotavirus strains that were typed were of serotypes G 1-4. There was no significant difference among rotavirus-positive and rotavirus-negative patients with regard to family income. Compared with children who were exclusively breast-fed, those who were not exclusively breast-fed were at a two-fold greater risk of rotavirus diarrhea. Rotavirus gastroenteritis was significantly more severe than non-rotavirus gastroenteritis; 69% of children with rotavirus infection had severe gastroenteritis (score > or = 11). In conclusion, rotavirus is the most common cause of severe gastroenteritis among children under five years of age in Izmir. A new potent rotavirus vaccine, when available, will provide effective protection against severe rotavirus infection. Promotion of breast-feeding would augment the impact of rotavirus vaccines in preventing severe childhood diarrhea.     

Rotavirus,adenovirus, and non-viral enteropathogens in diarrhoea.

The aetiology of rotavirus and adenovirus in acute gastroenteritis was studied in a prospective series that comprised 283 children admitted consecutively with diarrhoea during a 1-year period. Rotavirus was associated in 49% of the cases by solid-phase radioimmunoassay and electron microscopical examination of stool specimens, or by serology. Adenovirus was detected by radioimmunoassay in the stool specimens of 29 (11%) patients, including 8 cases of possible dual infection with rotavirus. Rotavirus infections showed a typical age distribution and seasonal clustering between January and June, whereas the adenovirus-associated cases did not form a distinctive subgroup. Enteropathogenic bacteria were found in 10% of cases, and were nearly as common in association with rotavirus infection as not. Respiratory symptoms accompanied diarrhoea in 34% of the patients with rotavirus and in 25% of those with neither rotavirus nor adenovirus. Therefore we could not confirm the existence of a ''rotavirus syndrome'', nor could we confirm an association of respiratory symptoms with rotavirus infection. Use of antibiotics before the onset of diarrhoea was more common among those with non-viral diarrhoea (23%) than in the rotavirus group (13%). Rotavirus infections appeared to be common among cases of ''antibiotic-induced'' diarrhoea.     

Acute diarrhoea and rotavirus infections in young children in Kuwait

The role of rotavirus infections in acute diarrhoea in young children was studied over a period of one year. Rotavirus was detected by electron microscopy and enzyme immunoassay methods in 40.2% of faecal specimens from 343 children with acute diarrhoea and in 4.7% of 86 controls. The infections were most common in children aged 2-12 months (42.3%). Twelve per cent of the rotavirus infected children were also infected with bacterial enteropathogens (Salmonellae, Shigellae and enteropathogenic Escherichia coli). The incidence of rotavirus infections was not related to sex, socio-economic or nutritional status of children. Rotavirus-associated diarrhoea differed in several clinical parameters from bacterial associated and nonspecific diarrhoea. Rotavirus was detected throughout the year but was most frequent during months with little rainfall and low humidity (March-May). Our results suggest that in Kuwait, rotavirus infection is a major cause of childhood diarrhoea.     

Kliniczna i laboratoryjna charakterystyka infekcji rotawirusowych u dzieci

IntroductionRotavirus infections are the major cause of gastroenteritis, frequently lead to hospitalization, and even death of children around the world.AimAnalysis of the clinical image of rotavirus infections in children and determination of the kind and frequency of systemic complications which result from them.Material and MethodsFrom among 176 patients hospitalized due to dehydrations during gastroenteritis, children with rotavirus etiology infections, diagnosed basing on stools samples tests, were separated. Patients were divided into 3 age subgroups, their clinical image and the frequency of complications were examined.ResultsRotavirus infections were diagnosed in 87 patients (49%), in the average age of 39.66 months, most frequently in boys (52.87%). In the clinical image predominated watery diarrhea (93%), vomiting (85%), and fever (43%). The average duration of the children's hospitalization was 6 days. Complications developed in 26 children (29.89%), including: an increase of aminotransferase activity in 13, pneumonia in 7, and neurological complications in 6 children. In 4 patients single episodes of convulsions were observed, in 2 children rotavirus neuroinfections were diagnosed. One child required treatment in an intensive care unit. In one patient after rotavirus infection neurological complications are still observed. More frequent occurrence of complications in the subgroup of the youngest and chronically ill children was noted.ConclusionsDuring rotavirus infections great number of organ complications may appear, including the especially dangerous for health and life neuroinfections. Therefore, common use of rotavirus vaccinations is very important for children health.     

Multicenter prospective study analysing the role of rotavirus on acute gastroenteritis in Spain

Background: Paediatric rotavirus gastroenteritis is the most frequent cause of acute gastroenteritis (AGE) in children up to 5 years of age worldwide. Aim: To analyse the clinical characteristics of AGE caused by rotavirus comparing to AGE caused by other agents. Methods: The study was conducted in 30 health‐care centers in Spain (25 hospitals and five primary centers) between January and March 2006. Children with AGE up to 2 years of age were included. Stool samples were analysed using immunochromatographic test to identify rotavirus infection. Clinical and epidemiological data were analysed. Results: A total of 1192 children were enrolled (mean age: 11.2 months). Fever, Vomiting, weakness and dehydration were more frequent in rotavirus‐positive AGE cases. Severity score was higher and hospitalization was likely in AGE caused by rotavirus. Family AGE illness was more frequent in children with rotavirus‐positive AGE. Breastfeeding was found as a protective factor against Rotavirus AGE. Conclusion: Rotavirus is the primary causal agent of AGE in children under 2 years of age in Spain, causing more severe symptoms and more hospital admissions than other causal agents. Our data support the interest of the introduction of the available rotavirus vaccines in the Spanish immunization schedule.     

Effect of Lactobacillus GG and breast-feeding in the prevention of rotavirus nosocomial infection

BACKGROUND: Rotavirus is one of the leading etiologic agents of nosocomial infections among children. The development of preventive measures is therefore important. The efficacy of GG in the treatment of rotavirus infection has been reported in literature, but there is only one recent study about its effectiveness in prevention of infection. The role of breast-feeding in the prevention of rotavirus infection is still debated. The aim of our study was to assess the efficacy of GG and breast-feeding in the prevention of nosocomial rotavirus infections. METHODS: In a randomized, placebo-controlled, double-blind study, 220 children aged 1 to 18 months hospitalized from December 1999 to May 2000, received GG (n = 114) at a dose of 10 colony-forming units or a comparable placebo (n = 106) every day of their hospital stay. Rotavirus testing on stool samples was performed for every patient on admission, during hospitalization, and after discharge. RESULTS: The total incidence of nosocomial rotavirus infections was 27.7% (61 of 220 patients). The attack rate of rotavirus infections among the patients who received probiotic was 25.4% (29 of 114 patients), while for the placebo group it was 30.2% (32 of 106 patients). The difference is not significant (P = 0.432). Forty-seven of 220 infants (21.4%) were breast-fed, and 173 of 220 (78.6%) were non-breast-fed. The attack rate of rotavirus infections among breast-fed infants was 10.6% (5 of 47 infants), while for non-breast-fed infants it was 32.4% (56 of 173 infants). The difference is significant (P = 0.003). CONCLUSION: In our study, GG was ineffective in preventing nosocomial rotavirus infections, whereas breast-feeding was effective.     

Rotavirus studies in Indian (Asian) South African infants with acute gastro-enteritis: I. Microbiological and epidemiological aspects.

This study, which is the first one documenting rotavirus (RV) diarrhoea in Asian infants in South Africa, describes the virological and epidemiological aspects of this disease in this population. Fifty-five per cent of 1142 hospitalized cases investigated over a 31-month period showed a positive stool ELISA for RV. Most of these children stopped shedding RV by days 4-6 of hospital admission, though prolonged excretion was recorded in some acute cases for up to 13 days. Mixed RV-bacterial infections occurred in 7% of the total gastro-enteritis (GE) patients, while 8.6% had pure bacterial gastro-enteritis. Sixteen per cent of 188 GE patients had serum anti-RV complement-fixing (CF) antibodies on admission. Rotavirus diarrhoea occurred in half of the seropositive infants. Seroconversion occurred in only two-thirds of the initially seronegative children who had RV diarrhoea. In 5.6% of the RV diarrhoea patients the infection was acquired nosocomially whilst in the hospital for other illnesses. The age-groups mainly affected were between 3 and 14 months, with a peak at 9-11 months; 3% of the RVGE patients were neonates. Both the RVGE and the total GE admissions showed well-marked winter peaks, with an inverse relationship between RV prevalence and both temperature and humidity. It is concluded that RV is the most important cause of infantile GE in this population, whereas pure bacterial infections play a relatively minor role. Circulating anti-RV antibodies do not necessarily afford protection against RV diarrhoea, probably owing to serotypic differences.     

Epidemiology and impact of rotavirus diarrhoea in Poland

Hospital and laboratory data were analysed in three hospitals to estimate rotavirus disease burden in 1994-96. Community acquired gastroenteritis was diagnosed in 757 children of whom 41% tested positive for rotavirus. A total of 196 children had rotavirus nosocomial infections (39% of all rotavirus community-acquired and nosocomial cases) Infants less than 24 months old and children less than 3 months old comprised 74% and 11.9% of admissions for rotavirus, respectively. Almost 94% of children with rotavirus infection had severe gastroenteritis (score 11). The annual rate of rotavirus associated hospitalization in Poland in 1996 was 3.1/1000 children under the age of 60 months and 5.2/1000 infants under 24 months of age. The mean hospital stay was 9.5 d (±9.8 d). We estimated that 8918 children under 60 months of age were hospitalized for rotavirus gastroenteritis in 1996; they accounted for 84899 inpatient days. We conclude that rotavirus is a leading aetiological agent of severe gastroenteritis in young children in Poland and that the Burden of this infection is significant. Rotavirus vaccine could significantly decrease the hospitalization rate and the financial impact of rotavirus Gastroenteritis in Poland. □ Acute diarrhoea, disease burden, epidemiology, gastroenteritis, rotavirus     

Epidemiology and impact of rotavirus diarrhoea in Poland

Hospital and laboratory data were analysed in three hospitals to estimate rotavirus disease burden in 1994-96. Community acquired gastroenteritis was diagnosed in 757 children of whom 41% tested positive for rotavirus. A total of 196 children had rotavirus nosocomial infections (39% of all rotavirus community-acquired and nosocomial cases). Infants less than 24 months old and children less than 3 months old comprised 74% and 11.9% of admissions for rotavirus, respectively. Almost 94% of children with rotavirus infection had severe gastroenteritis (score > or =11). The annual rate of rotavirus associated hospitalization in Poland in 1996 was 3.1/1000 children under the age of 60 months and 5.2/1000 infants under 24 months of age. The mean hospital stay was 9.5 d (+/-9.8 d). We estimated that 8918 children under 60 months of age were hospitalized for rotavirus gastroenteritis in 1996; they accounted for 84899 inpatient days. We conclude that rotavirus is a leading aetiological agent of severe gastroenteritis in young children in Poland and that the burden of this infection is significant. Rotavirus vaccine could significantly decrease the hospitalization rate and the financial impact of rotavirus gastroenteritis in Poland.     

Nonmedical costs associated with rotavirus disease requiring hospitalization

BACKGROUND: As the most common cause of severe diarrhea among children, rotavirus has a significant economic impact. Previous studies focused on the direct medical costs of rotavirus infections; however, nonmedical costs account for the majority of the financial burden from this disease. Herein, we report the results from the largest prospective study in the United States determining the nonmedical costs of severe rotavirus infections. METHODS: Prospective, active, gastroenteritis case surveillance was conducted between November 1997 and December 1999 at 3 pediatric medical centers. Rotavirus infection was identified for 548 children admitted between 2 weeks and 5 years of age. Detailed information about nonmedical costs during the prehospitalization, hospitalization and posthospitalization periods was obtained through interviews. RESULTS: The average nonmedical cost per case of rotavirus disease was USD $448.77, including $359.04 for missed work, $56.66 for transportation, $11.90 for oral rehydration solutions, $9.59 for diapers, $6.83 for child care changes, $3.82 for special foods and $0.93 for formula changes. More than one-half of these expenses (53%) occurred outside the hospitalization period, and 80% of the cost was attributable to missed work. CONCLUSIONS: With an estimated 50,000 hospitalizations attributable to rotavirus each year in the United States, the nonmedical costs of severe rotavirus infections may exceed USD $22 million annually. Previous cost effectiveness analyses of rotavirus vaccines substantially underestimated this burden, suggesting that the nonmedical costs associated with mild to moderate rotavirus disease have been similarly underestimated. These findings are needed to assess accurately the cost effectiveness of future rotavirus immunization strategies.     

Evaluation of a prevention program against nosocomial rotavirus infections in a pediatric ward]

The incidence of nosocomial rotavirus infections was evaluated by a study made in the pediatric ward in Cholet during the winter of 1993-1994. A second study was performed three years later at the same place and in similar conditions in order to evaluate the efficacy of the prevention measures taken in between. PATIENTS AND METHODS: All children below three years of age and admitted to hospital between 1 December 1996 and 15 March 1997 were included in the prospective study (348 children). Fecal specimens were collected for each patient at admission in order to search for rotavirus. Then, a second stool analysis was performed if diarrhea occurred during hospitalization or within 48 hours of discharge. These last cases were detected by a phone call. RESULTS: Thirty percent of the children had diarrhea at admission to hospital (19.3% in 1993-1994). Rotavirus was present in 11.8% of the first stool analyses (8.6% in 1993-1994). The rotavirus nosocomial infection rate has decreased from 3.7% (13 cases) in 1993-1994 to 2.9% (ten cases). The mean length of hospitalization has also decreased from 2.7 to 1.6 days. CONCLUSION: The decrease in the rotavirus nosocomial infection rate leads to enforcing the prevention measures, among which the most important seems to us to be the short length of stay. However, the study also shows the limits of prevention that are linked to the virus characteristics and the conditions of hospitalization.