Gastroenteritis Patients Research Articles

Acidosis with hyperuricemia and renal tubular damage in viral gastroenteritis

Acidosis with hyperuricemia and renal tubular damage in viral gastroenteritis

Water outage increases the risk of gastroenteritis and eyes and skin diseases

BackgroundThe present study used insurance claims data to investigate infections associated with short-term water outage because of constructions or pipe breaks.MethodsThe present study used medical claims of one million insured persons for 2004-2006. We estimated incidences of gastroenteritis and eye and skin complaints for 10 days before, during, and after 10 days of water supply restriction for outpatient visits and for emergency and in-patient care combined.ResultsThere was an increase in medical services for these complaints in outpatient visits because of water outages. Poisson regression analyses showed that increased risks of medical services were significant for gastroenteritis (relative risk [RR] 1.31, 95% confidence interval [CI] 1.26-1.37), skin disease (RR 1.36, 95% CI 1.30-1.42), and eye disease patients (RR 1.34, 95% CI 1.26-1.44). Similar risks were observed during 10-day lag periods. Compared with those in cool days, risks of medical services are higher when average daily temperature is above 30°C for gastroenteritis (RR 12.1, 95% CI 6.17-23.7), skin diseases (RR 4.48, 95% CI 2.29-8.78), and eye diseases (RR 40.3, 95% CI 7.23-224).ConclusionWe suggest promoting personal hygiene education during water supply shortages, particularly during the warm months.

Analysis of rotavirus antigenemia in hematopoietic stem cell transplant recipients

Systemic rotavirus infection, such as rotavirus antigenemia, has been found in immunocompetent rotavirus gastroenteritis patients. However, the pathogenesis of rotavirus infection in immunocompromised transplant recipients remains unclear. Enzyme-linked immunosorbent assay was used to measure rotavirus antigen levels in serially collected serum samples obtained from 62 pediatric patients receiving allogeneic hematopoietic stem cell transplants (HSCT). Rotavirus antigen was detected in 43 (6.8%) of 633 serum samples (8 of 62 patients). The duration of rotavirus antigenemia ranged between 1 and 10 weeks, and diarrhea was concurrent with rotavirus antigenemia in Cases 3, 6, 7, and 8. The level of viral antigen in the transplant recipients (0.19 ± 0.20) was significantly lower than that observed in serum samples collected from immunocompetent patients on either day 1 (0.49 ± 0.18, P = 0.0011) or day 3 (0.63 ± 0.09, P = 0.0005). A patient who received a graft from a human leukocyte antigen (HLA)-mismatched donor was at significant risk for rotavirus antigenemia (P = 0.024; odds ratio = 9.44) in comparison to patients who received grafts from HLA-matched donors. Although the duration of antigenemia was clearly longer in HSCT patients than in immunocompetent rotavirus gastroenteritis patients, the levels of viral antigen were not as high. Therefore, mismatched HLA may be a risk factor for rotavirus antigenemia after HSCT.

부산지역에서 분리된 norovirus 유전자형 연구

2008년부터 2010년까지 최근 3년 동안 부산지역에서 산발적으로 발생한 급성 위장관염 환자를 대상으로 유전자를 검사한 결과 4,101건 중 426건(10.4%)에서 노로바이러스를 확인하였다. 연도별 검출현황은 2008년에 14.7%(222/1,506), 2009년에 6.9%(95/1,384), 2010년에 9.0%(109/1,211)로 나타났다. 월별 분석 결과는 2008년에는 3월에 35.7%(50/140)로 가장 높은 검출율을 보였고, 2009년 역시 3월에 21.9%(23/105)로 높게 나타났으며, 2010년에는 1월에 23.8%(29/122)로 높은 검출율을 보여 겨울절기에 노로바이러스가 유행하는 것을 알 수 있었다. 반면 매해 7-8월 여름절기에는 노로바이러스가 거의 분리되지 않았다. 연령별 로는 1세 영아군과 13-19세 중등학생군에서 각각 20.9%로 가장 높은 검출율을 나타내었으며, 2-6세 소아군에서 17.5%, 20-29세군에서 13.4%, 7-12세 초등학생군에서 12.7%, 30-39세군에서 9.1%, 0세 신생아군에서 8.7%, 50-59세군에서 7.2%, 60-69세군과 70세이상군에서 각각 6.7%, 40-49세 4.5%로 확인되었다. 노로바이러스 양성 검체 340건에서 유전자형을 분석한 결과 GI군 7종류, GII군 13종류로 총 20종류가 검출되어 다양한 유전자형의 노로바이러스들이 유행함을 알 수 있었다. 연구 결과 부산지역에서는 GI군이 21.8%(76/348), GII군이 78.2%(272/348)로 GII군이 우세하여 유행하였고, 유전자형 총 20종 중 GII.4형이 49.1%로 가장 많이 검출되었다. Norovirus (NoV) causes major acute non-bacterial gastroenteritis in humans. NoV genus is a member of the family Caliciviridae, which is transmitted by contaminated food and water or from human to human. Many genotypes of genogroups I and II have been reported because of their high genetic diversity. To obtain molecular epidemiological information on gastroenteritis sporadic cases in Busan, Korea, we analyzed the nucleotide sequences of NoV strains detected during 2008~2010. We performed one step RT-PCR amplifying the open reading frame (ORF) 2 (capsid region) followed by semi-nested PCR. Fecal samples were collected from 4,071 acute gastroenteritis, and genotypes of the 421 positive samples were determined by sequence analysis. Based on partial sequence of capsid region, 7 NoV were categorized into genogroup I and 13 into genogroup II. Prevalent genotypes among gastroenteritis patients within Busan were GII.4, GI.6, GII.5 in 2008~2010. The results of this study will contribute to the currently available epidemiological data and improve public health and hygiene via development of diagnostic methods and sustainable surveillance.

Empiric antimicrobial therapy and infectious diarrhea. Do we need local guidelines?

Background In the management of acute diarrhea, administration of antibiotics may be indicated. Appropriate antimicrobial therapy can shorten illness, reduce morbidity and can be life-saving in invasive infections. Emergence of microbial strains resistant to commonly used antibiotics means that treatment failures may become common. Because of changing patterns of resistance, knowledge of recent local patterns of susceptibility can guide the initial choice of antibiotics. Methods A retrospective study was conducted to investigate the epidemiology of infective gastroenteritis in patients over 14 years old in the region of Chania (Crete). We reviewed all positive stool cultures and susceptibilities of the pathogens recovered from patients with symptoms of acute diarrhea, from 2003 until October 2010. Results Out of 194 positive stool cultures, we observed 139 cases of Salmonella enterica and 48 cases of Campylobacter jejuni. During the last 3 years of observation there was an increased incidence of C. jejuni, especially after the tap water outbreak that occurred in our region in 2009. Discussion In the vast majority of acute diarrhea in adults, antibiotics are of no benefit and overprescription may confer to side effects, costs and emergence of resistance. Antibiotics are initiated in cases of febrile diarrheas especially those believed to have moderate to severe disease. Considering the increased incidence of C. jejuni and the resistance of the great majority of isolated strains to quinolones as well as the sensitivity of Salmonella spp. to azithromycin, administration of azithromycin empirically for acute diarrhea, when indicated, could be appropriate in our region.

Rectal swabs can be used for diagnosis of viral gastroenteritis with a multiple real-time PCR assay

Background Viral agents, especially norovirus, are the most common cause of nosocomial spread of epidemic gastroenteritis (GE). Rapid and reliable detection of these agents could reduce the risk of outbreaks. Objective To evaluate the diagnostic performance of rectal swab samples compared to standard stool samples for detection of agents causing viral GE by PCR. Study design Complete pairs of rectal swab and stool samples, obtained simultaneously from patients with symptoms of acute onset GE, were analysed with a multiple real-time PCR targeting six different gastroenteritis agents (astro-, adeno-, rota-, sapo- and norovirus GI and II). Cycle threshold (Ct) values were registered for positive samples. A positive PCR result in either sample for any virus was considered gold standard. Results 69 sample pairs were included of which 29 were negative in both sample types and 38 were positive in both sample types. One pair was positive in the stool sample only and another pair was positive in the rectal swab sample only. Sensitivity for both sample types was 97.5% (39/40). Conclusion Rectal swab samples are as reliable as stool samples for PCR-based diagnosis of viral gastroenteritis in patients with a short duration of symptoms and may be used as a complement to stool samples, especially when immediate sampling is desirable.

Epidemiological and clinical characteristics of pediatric gastroenteritis associated with new viral agents

A 22-month study (2008-2009) was carried out on 273 patients (average age 40 months), admitted with gastroenteritis to the Pediatric Unit of L. Sacco University Hospital in Milan, Italy. Fecal samples were investigated for rotavirus (HRV), norovirus (NoV), adenovirus (AdV), sapovirus (SaV), enterovirus, astrovirus and bocavirus (HBoV). A 38.3% incidence of infection was observed for HRV, followed by NoV (16.2%), HBoV (13.6%), AdV (2.6%) and SaV (0.6%). Clinical evaluation of 109 gastroenteritis patients with confirmed diagnosis was graded by the Ruska-Vesikari scoring system, showing vomiting (78%), diarrhea (96%) and fever (80%). A total of 25 NoV-positive samples were selected for nucleotide sequence analysis. The severity of AdV-associated infection was lower than for NoV, HRV and HBoV. These latter viruses caused similar symptoms that were indistinguishable using clinical information. NoV, HRV and HBoV were often present as mixed infections (13.1%). Sequencing of NoV-positive samples allowed identification of GII.2, GII.3 and GII.4 2006 variants.

Prevalence of Salmonella, Yersinia and Campylobacter spp. in Feral Raccoons (Procyon lotor) and Masked Palm Civets (Paguma larvata) in Japan

SummaryTo estimate the public and animal health risk that alien species pose, the prevalence of Salmonella, Yersinia, and Campylobacter spp. in feral raccoons (Procyon lotor, n = 459) and masked palm civets (Paguma larvata, n = 153), which are abundant alien species in Japan, was investigated in urban and suburban areas of Japan. Salmonella enterica was detected from 29 samples [26 raccoons, 5.7%, 95% confidence interval (CI) 7.8–3.5%; three masked palm civets, 2.0%, 95% CI 4.2–0%]. Many of the isolates belonged to serovars that are commonly isolated from human gastroenteritis patients (e.g. S. Infantis, S. Typhimurium, and S. Thompson). The antimicrobial susceptibility test showed that 26.9 % of the isolates from raccoons were resistant to at least one antimicrobial agent, whereas none of the isolates from masked palm civets were resistant. Yersinia sp. was detected from 193 samples (177 raccoons, 38.6%, 95% CI 43.0–34.1%; 16 masked palm civets, 10.5%, 95% CI 15.3–5.6%). All virulent Yersinia strains belonged to Yersinia pseudotuberculosis, which was isolated from seven (1.5%, 95% CI 2.6–0.4%) raccoons and six (3.9%, 95% CI 7.0–0.8%) masked palm civets. According to the detection of virulence factors, all the Y. pseudotuberculosis isolates belonged to the Far Eastern systemic pathogenicity type. Campylobacter spp. was detected from 17 samples (six raccoons, 1.3%, 95% CI 2.3–0.3%; 11 masked palm civets, 7.2%, 95% CI 11.3–3.1%). Among these, three isolates from raccoons were identified as C. jejuni. These results showed that these pathogens can be transmitted by human activities, other wild animals, and the environment to feral raccoons and masked palm civets, and vice versa. As these animals have omnivorous behaviour and a wide range of habitats, they can play an important role in the transmission of the enteric pathogens.

An outbreak of gastroenteritis caused by contaminated well water in a village, Henan province

To identify the cause and mode of transmission of a gastroenteritis outbreak in a village, Henan province. Gastroenteritis patients were identified through family visits, interviewing the village doctors and reviewing diagnosis and prescription records at the village health clinic. Cases were defined as onset of one of the four symptoms from the village resident during July 20 to August 12, 2010. The symptoms would include diarrhea (≥ 3 times/day), abdominal pain, nausea or vomiting. A retrospective cohort study was conducted to assess the association between drinking raw well water or eating noodles rinsed by raw well water and gastroenteritis. Stools or vomits of the case-patients and the well water samples were tested for bacterial pathogens. Data for 60 case-patients were collected. All cases occurred in the northern part of the village. Persons who used water from a public well in the northern part of the village had an attack rate of 55%, which was 3.5 times of those who did not use the well water (16%) (RR = 3.5, 95%CI: 1.2 - 10). Results from the retrospective cohort study showed that drinking un-boiled water from the well was a risk factor (RR = 1.7, 95%CI: 1.3 - 2.3). Laboratory testing showed that total coliform and E. coli both greatly exceeded the limit considered safe for drinking, indicating there was fecal contamination in the well water. No bacterial pathogens were detected in the patients' stools or vomits. The outbreak was mainly caused by drinking contaminated water from the public well in the northern part of the village.

Molecular characterization of partial-open reading frames 1a and 2 of the human astroviruses in South Korea

Human astroviruses (HAstVs) are among the major causes of gastroenteritis in South Korea. In this study, the partial regions of the open reading frame (ORF) 1a and ORF2 genes of HAstVs from gastroenteritis patients in nine hospitals were sequenced, and the molecular characterization of the viruses was revealed. 89 partial nucleotide sequences of ORF1a and 88 partial nucleotide sequences of ORF2 were amplified from 120 stool specimens. Phylogenetic analysis showed that most of the nucleotide sequences of ORF1a and ORF2 were grouped with HAstV type 1 but had evolutionary genetic distance compared with the reference sequences, such as the HAstV-1 prototype, Dresden strain, and Oxford strain. According to the phylogenetic analysis, some nucleotide sequences including SE0506041, SE0506043, and SE0506058, showed the discrepancy of the genotypes, but there was no proof of recombination among the HAstV types. In conclusion, this study showed that the dominant HAstV isolated from the Seoul metropolitan area in 2004-2005 was HAstV type 1, and that Korean HAstV-1 had the genetic distance in evolution compared with the reference sequences of HAstVs. Lots of nucleotide sequences of the ORF1a and ORF2 genes of HAstV will be useful for studying for the control and prevention of HAstV gastroenteritis in South Korea.

Prevalence of extended spectrum beta lactamases in Salmonella species isolated from patients with acute gastroenteritis

Extended-spectrum β-lactamases (ESBLs) continue to be a major problem world wide, conferring resistance to the expanded-spectrum cephalosporins. They are increasingly associated with genus Salmonella. This study aimed to determine the prevalence of ESBLs in Salmonella isolates in our region by phenotypic methods. One thousand stool samples of acute gastroenteritis patients were screened and 42 strains of Salmonella (19 S. typhimurium, 14 S. enteritidis, 5 S. typhi, 3 S. paratyphi B 3 and 1 S. infantis) were detected. In the 3rd generation cephalosporin resistant Salmonella stains, ESBL was detected by double disc synergy test in ten isolates and by phenotypic confirmatory test in eight isolates of Salmonella. Drug resistance to various antibiotics was noted both among ESBL producers and non-ESBL producers. Resistance to chloramphenicol, nalidixic acid, norfloxacin and ciprofloxacin was noted in ESBL producers (n=4, 3, 8 and 8 of eight cases respectively) and in non-ESBL producers (n=10, 9, 16 and 13 of 34 cases, respectively). Quinolone resistance was significantly higher in ESBL producers while imipenem and cotrimoxazole resistance was significantly higher in non-ESBL producers. ESBL positive Salmonella isolates were found to be sensitive to amikacin and amoxyclav. The proper and regular monitoring of drug resistance ESBL production among Salmonella strains were necessary for the effective therapeutic outcome.

Current situation of Cryptosporidium and other enteroparasites among patients with gastroenteritis from western cities of Mazandaran province, Iran, during 2007-2008

Aim : The aim of this study was to evaluate the prevalence rate of Cryptosporidium and other enteropathogen parasites among patients with gastroenteritis in western cities of Mazandaran province, northern Iran, during one year. Background : As specific characterization, high humidity, ecological conditions, superficial water sources, municipal water supplies, domestic and industrial animal husbandry and the rate of raining made Mazandaran as a favorable province for transmission of parasitic diseases. Patients and methods : This investigation was conducted between June 2007 to June 2008 in western cities of Mazandaran province, Northern Iran. Overall, 420 stool samples of gastroenteritis patients were collected from Chalous (194 sample), Tonekabon (187 sample) and Ramsar (39 sample), fixed and examined by Direct Method (DM) for diagnosis of enteropathogen parasites, Acid-Fast Staining (AFS) and Auramin Phenol Fluorescence (APF) for detection of Cryptosporidium and other sporozoan protozoa. Results : The results confirmed the overall prevalence rate of parasitic infections to be 2.14% (9 patients) among those cities, and the highest rate of infection was observed to be among Giardia lamblia (1.19%, 5 patients), Blastocystis hominis (0.71%, 3 patients) and Entamoeba coli (0.24%, 1 patient) respectively. There was no Cryptospordium and other sporozoan infection among the test samples. Comparative prevalence rates of parasitic infections in Chalous, Tonekabon and Ramsar were 1.55% (3 patients), 2.14% (4 patients) and 2.56% (1 patient) respectively. The relative frequencies of parasitic infections among infected individuals were associated with seasons, therefore the highest and the lowest rates were observed in autumn (40%) and spring (10%), respectively. Conclusion : Although, the current results showed a decline in the rate of parasitic infections in Mazandaran province recently in comparison with the past previous studies, the situation is always under caution for emerging and re-emerging enteropathogen parasites with the emphasize on opportunistic parasites.

Detection of Sapovirus in oysters

SaV sequences which are either genetically identical or similar were detected from oysters, feces from gastroenteritis patients, and domestic wastewater samples in geographically close areas. This is the first report of the detection of SaV in oysters which meet the legal requirements for raw consumption in Japan.

Characteristics of rotavirus gastroenteritis in hospitalized children in Pune

Diarrheal diseases affect millions of people around the world and have the greatest impact on children, especially those in developing countries. Rotavirus is now known to contribute significantly to the etiology of diarrheal diseases in both developing and developed countries. To study demographic, clinical, and laboratory characteristics of rotavirus infection in cases of acute diarrhea admitted in the hospital who were below the age 5 years. It was a prospective study conducted from June 2009 to June 2011 to determine characteristics, clinical profile, and antigenemia of rotavirus. The study group included patients up to 5 years of age hospitalized with a diagnosis of acute gastroenteritis. Statistical analysis was done using the chi-square test. Data were analyzed using SPSS (Statistical Package for Social Sciences) version 17.0. From the 246 cases studied in the hospitalized patients of acute gastroenteritis, 88 cases (35.77%) were found to be positive for rotavirus infection. The occurrence of infection was found to be most common in the age group of 11-20 months (38.63%) followed by the age group of 0-10 months (23.86%). There was no association with the sex of the child. In rotavirus-positive patients, associated features were fever in 48.86%, vomiting in 29.54%, and pain in abdomen in 53.4% of cases. Seasonal variation of rotavirus infection was observed in the present study with peak in the winter season. It was found that 5.68% cases which were positive for rotavirus in their stool samples were positive for rotavirus present in their urine sample, suggesting extraintestinal manifestation of rotavirus. It is concluded that in spite of clean hygienic condition and vaccination rotavirus is still an important cause of infantile diarrhea in urban area like Pune. There is association between the occurrence of rotavirus and degree of dehydration, fever, vomiting, and pain in abdomen. Peak incidence was found in the months of December and January. There is association between the occurrence of rotavirus in stool and rotavirus in blood.

Duodenal Eosinophilia in Eosinophilic Esophagitis

Purpose: Eosinophils are present throughout the GI tract with the exception of the esophagus. The significance of increased eosinophils in the duodenum is not well understood. Duodenal eosinophilia has been seen in dyspepsia but has not been well studied in eosinophilic esophagitis (EoE). The aim of this study is to characterize gastric and duodenal eosinophilia in patients with EoE and non-ulcer dyspepsia (NUD). Our hypothesis is that there is increased duodenal eosinophilia in EoE and NUD compared to control patients. We also hypothesize that there is no difference in gastric eosinophilia among these groups. Methods: A retrospective chart review was done to gather information on baseline characteristics. Gastric and duodenal biopsy histopathology was prospectively reviewed. Eosinophils were counted in five high power fields. The mean eosinophil count was calculated for each patient. Each group had about thirty patients. The NUD patients met Rome III criteria. A small group of eosinophilic gastroenteritis (EG) patients were also compared to controls. Patients with malignancies, hypereosinophilic syndrome, inflammatory bowel disease, infections, H. pylori, myeloproliferative disease, collagen vascular disease, celiac disease and alcohol abuse were excluded from the study. Results: Duodenal eosinophil counts for EoE patients ranged from 1 to 54, with a mean of 8. Ranges in the other three groups were smaller. The median duodenal eosinophil counts for EoE (5.5) and NUD (4.3) were higher than the control group (4), p<0.05. There was no statistically significant difference between the median duodenal eosinophil counts of EG (4.8) and controls (4). The median gastric eosinophil count for EG (28.7) was higher than the control group (4.2), p<0.05. There was no statistically significant difference between the median gastric eosinophil counts of EoE patients (4.4), NUD patients (3) and control patients (4.2). Conclusion: Patients with EoE and NUD have increased duodenal eosinophilia compared to control patients. The median eosinophil count of the EG group was higher than the control group and NUD group. However, there was probably no statistically significant difference between EG and control patients due to the relatively small number of EG patients. The similarity of gastric eosinophil counts among the EoE, NUD and control patients is consistent with prior studies. The high gastric eosinophil count of the EG group is consistent with their diagnosis. The median eosinophil counts in this study may be lower than prior studies due to higher percentage of female patients, younger age, and exclusion of patients with H. pylori. Duodenal eosinophilia in EoE is a novel finding and additional studies will need to done.

Molecular characterization of hepatitis A virus isolated from acute gastroenteritis patients in the Seoul region of Korea

Hepatitis A virus (HAV) is a major public health problem throughout the world. As a result of declining HAV endemic in Korea, an increasing number of children and adolescents have become susceptible to HAV infection. HAV is related with sanitation conditions of the environment and is transmitted via the fecal-oral route, either through person-to-person contact or by contaminated water and food. The present study has been carried out to determine the phylogenetic analysis and circulating patterns of HAV strains detected from hospitalized patients with acute gastroenteritis (AGE) in the Seoul region of Korea. In total, 2,782 stool specimens from hospitalized patients with AGE collected in October 2006 to September 2007 in Seoul were tested for HAV. A pair comparison of the nucleic acid sequence of a 159-bp base region at the putative VP1/2A junction of 85 Seoul isolates revealed that the most common HAV strain circulating in the region during 2006-2007 was subgenotype IA. HAV phylogenetic studies can provide important information on the genetic characteristics of HAV from AGE patients who may subsequently become the source of infection in Korea.

Clinical Characteristics of Benign Convulsions With Rotavirus Gastroenteritis

Convulsions sometimes occur in infants and toddlers with mild gastroenteritis. We retrospectively investigated the hospital records of 106 patients admitted to our hospital who had rotavirus gastroenteritis from February 2002 to April 2008. There were 23 patients with convulsions, including 13 with benign convulsions, 9 with febrile seizures, and 1 with epilepsy. Gastroenteritis in patients with benign convulsions was mild from the viewpoint of body weights and serum creatinine concentrations on admission and the duration of admission. Serum Na(+) and Cl(-) concentrations of patients with benign convulsions were relatively lower than those without convulsions on admission (P = .006, and P = .008, respectively). Twelve of thirteen patients had no other seizures after oral administration of 5 mg/kg of carbamazepine, while 1 patient had 1 convulsion 15 minutes after the therapy. In conclusion, carbamazepine therapy was effective for benign convulsions with rotavirus gastroenteritis.

Prolonged norovirus outbreak in a Finnish tertiary care hospital caused by GII.4-2006b subvariants

Norovirus outbreaks are difficult to control in hospitals. Cohorting and contact isolation, disinfective surface cleaning and hand hygiene are key elements in outbreak control. A new norovirus variant, GII.4.-2006b, spreading across many continents, caused an exceptionally long epidemic period in Finland, from November 2006 to June 2007. Here, we describe the clinical and molecular characteristics of a norovirus outbreak in a large tertiary care hospital in Finland. Altogether 240 (18%) patients and 205 (19%) healthcare workers fell ill in the 504 bedded main building of Helsinki University Central Hospital during December 2006 to May 2007. The epidemic curve had three peaks in January, February and April, and different wards were affected each time. During the outbreak, 502 patient stool specimens were tested for norovirus RNA, 181 (36%) of which were positive. Molecular analysis of 48 positive specimens revealed three main subvariants of GII.4.-2006b circulating temporally within distinct wards. Of all microbiologically confirmed cases, 121 (67%) were nosocomial and nine (5%) died within 30 days of diagnosis. Molecular analysis suggested that the three main GII.4-2006b subvariants entered the hospital with gastroenteritis patients, and the nosocomial spread within wards coincided with the epidemic peaks. Active control measures, including temporary closure of the wards, ultimately confined the single-ward outbreaks. A prolonged outbreak in the community was probably the source for the prolonged outbreak period in the hospital.

Detection, genetic characterization, and quantification of norovirus RNA from sera of children with gastroenteritis

Background Norovirus (NoV) infection is thought to be confined to the intestines, whereas many reports suggest antigenemia and viremia occur during rotavirus gastroenteritis. Objectives To detect NoV RNA in sera and cerebrospinal fluids (CSF) from NoV-infected children, and to quantify and genetically characterize the NoV found in these compartments. Study design Semi-nested PCR was conducted on stool, serum and CSF samples from 56 patients with acute gastroenteritis. Positive samples for NoV were analyzed further by sequencing and real-time PCR. Results From 39 patients with NoV RNA in stools, 6 also had NoV RNA in sera and none had NoV RNA in CSF. Genotypes of the NoV in stool and serum from the same patient matched completely. The strains in this study had high homology (98.1–100%) with registered strains in the database. The median viral load in stools of the serum-positive patients was greater than that of the serum-negative patients, but this difference was not statistically significant (9.8 × 10 9 copies/g versus 1.1 × 10 9 copies/g ( p = 0.117)). Conclusions NoV RNA appeared in the blood stream in 15% of the patients of NoV gastroenteritis. Although the viral load in stool was not statistically correlated with NoV appearance in serum, genetic analysis indicated that NoV RNA in sera originated from the NoV gastroenteritis.

A Survey of Intestinal Protozoan Infections among Gastroenteritis Patients during a 3-Year Period (2004-2006) in Gyeonggi-do (Province), South Korea

The incidence and etiology of parasite-associated gastroenteritis during 2004-2006 in Gyeonggi-do (province), South Korea was determined by means of antigen detection ELISA on 6,071 stool specimens collected from 6 general hospitals. At least 1 parasitic agent was detected in 3.4% (208/6,071) of the stool samples. Among these, Giardia lamblia was the most numerous (152 cases; 2.5%), followed by Entamoeba histolytica (25 cases; 0.4%), Cryptosporidium parvum (23 cases; 0.4%), and mixed infections (8 cases; 0.1%). Patients aged 1-5 years had the largest proportion (69.2%; 144/208) of parasite-positive stool specimens. Parasite-mediated gastroenteritis was most common from June to September. The detection rate gradually increased from 2004 to 2006. This study shows that parasite-mediated gastroenteritis may be significant among children in Korea and that parasite infection surveillance should be constantly performed.