Caliciviruses in hospitalized children, São Luís, Maranhão, 1997-1999: detection of norovirus GII. 12

ABSTRACT Gastroenteritis is one of the most common diseases during childhood, with norovirus (NoV) and sapovirus (SaV) being two of its main causes. This study reports for the first time the incidence of these viruses in hospitalized children with and without gastroenteritis in São Luís, Maranhão. A total of 136 fecal samples were tested by enzyme immunoassays (EIA) for the detection of NoV and by reverse transcription-polymerase chain reaction (RT-PCR) for detection of both NoV and SaV. Positive samples for both agents were subjected to sequencing. The overall frequency of NoV as detected by EIA and RT-PCR was 17.6% (24/136) and 32.6% (15/46), respectively in diarrheic patients and 10.0% (9/90) in non-diarrheic patients (p < 0.01). Of the diarrheic patients, 17% had fever, vomiting and anorexia, and 13% developed fever, vomiting and abdominal pain. Of the 24 NoV-positive samples, 50% (12/24) were sequenced and classified as genotypes GII.3 (n = 1), GII.4 (6), GII.5 (1), GII.7 (2), GII.12 (1) and GII.16 (1). SaV frequency was 9.8% (11/112), with 22.6% (7/31) in diarrheic patients and 4.9% (4/81) in nondiarrheic (p = 0.04) ones. In diarrheic cases, 27.3% had fever, vomiting and anorexia, whereas 18.2% had fever, anorexia and abdominal pain. One SaV-positive sample was sequenced and classified as GII.1. These results show a high genetic diversity of NoV and higher prevalence of NoV compared to SaV. Our data highlight the importance of NoV and SaV as enteropathogens in São Luís, Maranhão.

Expression of human norovirus VP1 gene and VP1-specific monoclonal antibodies / 동물의과학연구지

Norovirus (NoV) is an etiologic agent of human and animal acute gastroenteritis and is a member of the family Caliciviridae. NoV is classified based on nucleotide sequences of the VP1 gene into at least six genogroups (GI-GVI), among which GI, GII, and GIV are known to infect humans and GII is the most prevalent genogroup. In this study, VP1, the full gene of GII human NoV, was cloned from a human fecal sample and expressed using a baculovirus expression system. Human NoV VP1-specific monoclonal antibodies (MAbs) were produced using expressed recombinant VP1. Expressed VP1 in the recombinant virus was confirmed by polymerase chain reaction (PCR), indirect fluorescence antibody (IFA) test, and Western blot analysis. Eight hybridomas secreting VP1-specific MAbs against human GII NoV were generated and characterized. All of the MAbs produced in this study reacted with human GII NoV VP1-recombinant baculoviruses but not with other non-human calicivirus recombinant baculoviruses. These MAbs reacted specifically with human NoV GII.4-2009 virus-like particles (VLPs), and some MAbs showed cross-reactivity with other GII.4 variant VLPs. Expressed human GII NoV VP1-recombinant protein and MAbs specific to this protein can be used as useful reagents for detecting and characterizing human NoV.

Etiological study on cases with viral diarrhea in Ningxia during 2011 / 中华流行病学杂志

<p><b>OBJECTIVE</b>To investigate the etiological characteristics of human rotavirus (HRV), human calicivirus (HuCV), human astrovirus (HAstV) and human enteral adenovirus (HAdV) in Ningxia province during 2011.</p><p><b>METHODS</b>Stool specimen was collected from acute diarrhea case of Ningxia during 2011. HRV was detected by ELISA and serotype/genotype identified on those RT-PCR positive specimens. HuCV, HAstV and HAdV were detected by RT-PCR.</p><p><b>RESULTS</b>In this study, a total of 690 specimens were detected, with the infection rates of HRV, HuCV, HAstV and HAdV as 2.17%, 21.74%, 3.19% and 6.52%, respectively. Co-infections were found in 4.20% of all the samples being tested. Among 15 HRV positive cases, serotypes G1, G3 and P[4] were the most predominant strains.</p><p><b>CONCLUSION</b>Children who were under 2 years of age were the majority among patients infected by diarrhea viruses while HuCV was recognized as the main pathogen responsible for the viral diarrhea cases in Ningxia, 2011.</p>

Molecular and epidemiological study on among children under 5 years old in Nanjing / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To study the infected information, clinical symptom and molecular epidemiological characteristics of HuCV infection among children under 5 years old in Nanjing.</p><p><b>METHODS</b>In Nanjing Children's Hospital of Nanjing Medical University from July 2010 to June 2011, we collected 428 stool specimens from children with diarrhea and 428 asymptomatic controls. Human Calicivirus were tested by using RT-PCR. Then we sequenced the nucleic acid of PCR amplifications and identified the genotype and gene group of prevalent strains.</p><p><b>RESULTS</b>63 (14.72%) out of 428 stool samples were detected as HuCV. 58 were norovirus and 5 were sapovirus, while GII-4 2006b was the predominant strain of NoV. In the 428 control samples, 19 samples were positive for calicivirus, there were 8 NoV and 13 SaV (Including 3 co-infection cases).</p><p><b>CONCLUSION</b>Human caliciviruses with different genotypes circulated among children in Nanjing,and GII. 2006b is the dominant genotype.</p>

Molecular epideiological and clinical feature of human calicivirus and adenovirus among children with diarrhea less than 5 years old from 2010 to 2011 in Lanzhou, Gansu province / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To investigate the clinical and molecular epidemiology characteristics of calicivirus and adenovirus in children for viral diarrhea in Lanzhou.</p><p><b>METHODS</b>Stool samples were collected from 295 children with diarrhea at the First Hospital of Lanzhou University, Gansu Province,China, between July 2010 and June 2011. Reverse transcription-polymerase chain reaction (RT-PCR) or PCR were used to detected calicivirus and adenovirus. The adenovirus positive samples were typed by nested PCR and multiple PCR.</p><p><b>RESULTS</b>Of the 295 specimens, 13.2% (39/295) were positive for calicivirus, and 5.1% (15/295) were adenovirus. Typing and Phylogenetic analysis revealed that novirus GII-3 and adenovirus 41 were the dominant strains. Both calicivirus and adenovirus predominately affect children under the age of 2. In seasonal distribution, there was no obvious peak.</p><p><b>CONCLUSION</b>Human calicivirus and adenovirus are important pathogens of viral diarrhea,it is important to develop long-term systematic surveillance.</p>

Etiological and epidemiological study on viral diarrhea among children in Changchun / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To study the pathogen and characteristics of viral diarrhea in children in Changchun area.</p><p><b>METHODS</b>460 stools specimens were collected from children with acute diarrhea cured in the childrens, hospital of Changchun in 2010. Rotavirus were detected by ELISA, caliceverus and astrovirus were detected by reverse transcription-polymerase chain reactions (RT-PCR), adenovirus were detected by polymerase chain reactions (PCR).</p><p><b>RESULTS</b>A total of 460 specimens were detected. The detection rate of rotavirus, caliceverus, astrovious, adenovious respectively is 35.22%, 20.43%, 9.78%, 3.70%, the detectablerate of mixed infection is 7.61%, children under 2 years old were the major patient. The main genotypes of the virus: rotavirus (G3P[8]), caliceverus (GII-4), astrovious (type I), adenovious (Ad41).</p><p><b>CONCLUSION</b>Rotavirus is the main pathogen in Changchun. Followed by caliceverus, astrovious, adenovious.</p>

Molecular epidemiology of viral diarrhea in Chengdu infants and young children / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To investigated the molecular epidemiologic features of viral diarrhea in Chengdu infants and young children, and to establish baseline patterns of etiology, provides the scientific basis for the vaccine development and the epidemic situation control.</p><p><b>METHODS</b>From March, 2006 to December, 2008, a total of 376 infants and young children from Chengdu area hospitalized for diarrhea in Chengdu Children's Hospital were enrolled in this study. The stool specimen collected from each patient was tested for rotavirus (RV), Calicivirus (CV), astrovirus (AstV) and adenovirus (Adv) by using enzyme linked immunosorbent assay (ELISA) and reverse transcription-polymerase chain reaction (RT-PCR) examination.</p><p><b>RESULTS</b>Among those 376 cases,there were 142 cases (37.76%) of RV infections,which scattered predominantly in October to December. Among 234 cases RV negativity,there were 29 cases HuCV infections (15.85%), 5 cases AstV infections (1.64%), and 8 cases Adv infections (2.04%).</p><p><b>CONCLUSION</b>RV appeared to be the main etiological agent of viral diarrhea in Chengdu infants and young children,the predominant serotype of RV were G3, P[8] and P[4],HuCV might be the important etiological agent besides RV.</p>

First description of gastroenteritis viruses in Lebanese children: a pilot study

Human enteric viruses are important causes of acute gastroenteritis in infants and children. The role of rotaviruses, adenoviruses, human caliciviruses and astroviruses in the development of severe acute gastroenteritis requiring hospitalization of infants and young children in North Lebanon was investigated. Stool specimens collected between April and May 2010 from 79 Lebanese infants and children hospitalized for severe acute gastroenteritis, were screened for enteric viruses by immunoassays and internally controlled multiplex PCR assay. Out of 79 stool samples, 38 [48%] were positive for rotavirus, and 5 [6%] were positive for norovirus genogroup II. Enteric adenoviruses, sapoviruses and human astroviruses were not detected. Children with severe rotavirus gastroenteritis were younger than those with severe norovirus gastroenteritis. These results highlight the importance of rotavirus and norovirus as causes of severe gastroenteritis in Lebanese children, and the need to incorporate routine screening tests for norovirus infection in clinical settings

Molecular and epidemiological study on viral diarrhea among infants in Lanzhou / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To study the epidemiologic characteristics of viral diarrhea in children under 5 years old in Lanzhou, understand the four major virus in children of distribution.</p><p><b>METHODS</b>In the first hospital of Lanzhou university from Jul 2009 to Jun 2010,we collected 290 stool specimens from children with diarrhea and 114 asymptomatic controls. Rotavirus was detected by ELISA,further strain characterization was carried out by nested PCR. The human calicivirus, astrovirus, adenovirus were detected by RT-multiplex PCR and PCR.</p><p><b>RESULTS</b>At least one of the four viral agents was found in 60% of the specimens. Rotavirus, human calicivirus, adenovirus, and astrovirus were identified in 39.31%, 11.38%, 10.69%, and 4.83% in 290 specimens respectively. Rotavirus G3 was the most prevailing serotype, P [8] was the most common genotype. In the 114 control samples, 7 sample was positived for calicivirus, 5 samples were positived for human adenovirus and 1 sample was positived for astrovirus.</p><p><b>CONCLUSION</b>The results indicated clearly the impact of viral agents causing diarrhea and the importance of long-term systematic surveillance.</p>

Gastroenteric virus detection in fecal samples from women in Goiânia, State of Goiás, Brazil / Detecção de vírus gastroentéricos em amostras fecais de mulheres em Goiânia, Estado de Goiás, Brasil

INTRODUCTION: This was a prospective study that included women seen in the obstetrics and gynecology sector of Hospital das Clínicas, Federal University of Goiás, in Goiânia, State of Goiás, with the aim of detecting rotaviruses, adenoviruses, caliciviruses and astroviruses. Eighty-four women participated in the study and from these, 314 fecal samples were collected. Out of all of the women, 29 were seropositive for HIV and 55 were seronegative, and 45 and 39 were pregnant and non-pregnant, respectively. METHODS: Fecal samples were collected from each woman once every two months over the period from July 2006 to June 2007, and they were screened for rotaviruses by means of polyacrylamide gel electrophoresis and immunoenzymatic assays, for caliciviruses and astroviruses by means of RT-PCR and for adenovirus by means of immunoenzymatic assays. The astroviruses were genotyped using nested PCR. RESULTS: Among the 84 patients, 19 (22.6 percent) were positive for either calicivirus (14/19) or astrovirus (6/19), while one women was positive for both viruses in fecal samples collected on different occasions. Most of the positive samples were collected during the months of July and August (astrovirus) and September and October (calicivirus). None of the samples analyzed was positive for rotavirus or adenovirus. Gastroenteric viruses were detected in 13/19 (68.4 percent) of the pregnant women, whether HIV-seropositive or not. CONCLUSIONS: The results from the present study showed that neither pregnancy nor HIV-seropositive status among the women increased the risk of infection by any of the gastroenteric viruses studied. This study presents data on gastroenteric virus detection among pregnant and/or HIV-positive women.

INTRODUÇÃO: Este foi um estudo prospectivo que incluiu mulheres atendidas no setor de obstetrícia e ginecologia do Hospital das Clínicas da Universidade Federal de Goiás, em Goiânia, Estado de Goiás com o objetivo de detectar rotavírus, adenovírus, calicivírus e astrovírus. Oitenta e quatro mulheres participaram no estudo e destas, 314 amostras fecais foram coletadas. Do total de mulheres, 29 eram soropositivas para HIV, 55 soronegativas, 45 e 39 estavam grávidas e não-grávidas, respectivamente. MÉTODOS: Amostras fecais foram coletadas de cada mulher uma vez a cada dois meses pelo período de Julho-2006 a Junho-2007, foram triadas para rotavírus pela metodologia de eletroforese em gel de poliacrilamida (EGPA) e através de ensaio imunoenzimático (EIE), para calicivírus e astrovírus por RT-PCR e por EIE para adenovírus. Os astrovírus foram genotipados por Nested-PCR. RESULTADOS: De 84 pacientes, 19 (22,6 por cento) foram positivas para calicivírus (14/19) ou astrovírus (6/19), sendo que uma mulher foi positiva para ambos os vírus em amostras fecais coletadas em diferentes ocasiões. A maioria das amostras positivas foi coletada no período de Julho a Agosto (astrovírus) e de Setembro a Outubro (calicivírus). Nenhuma das amostras analisadas foi positiva para rotavírus ou adenovírus. Os vírus gastroentéricos foram detectados em 13/19 (68,4 por cento) mulheres grávidas, as quais eram HIV-soropositivas ou não. CONCLUSÕES: Os resultados do presente estudo mostram que nem o estado gravídico das mulheres nem a soropositividade para HIV aumentaram o risco para a infecção por nenhum dos vírus gastroentéricos estudados. Este estudo apresenta dados sobre a detecção de vírus gastroentéricos entre mulheres grávidas e/ou HIV-positivas.

[Detection of enteric viruses in wastewater of Monastir region by RT PCR method]

Wastewater frequently has been contaminated by enteric viruses, which can cause gastroenteritis, hepatitis, and other viral diseases. Since current water treatments do not ensure their complete removal and they become contaminants of the water environment. In order to monitor and assess the prevalence and the seasonal incidence of enteric viruses contaminating wastewater, a total of 93 samples were collected from the stations of Sayada-Lamta-Bouhjar and El Frina. The purpose of this study is to establish a rapid, sensitive and specific RT-PCR method using highly conserved primers to detect enteric viruses [caliciviruses, enteroviruses and hepatitis A viruses] circulating in the area of Monastir, during the period from October 2005 to July 2006. Our study shows that the caliciviruses were detected in 67.56%of the wastewater samples and present an essentially winter distribution with a specific peak in spring. The enteroviruses were detected in 35.13%of the samples tested and present a regular circulation during the year with a predominance in the summer and early fall. Finally, the presence of hepatitis A viruses was noted especially in winter in 10.81%of the wastewater samples. We notice that current wastewater treatment methods are sometimes not efficient to eliminate enteric viruses

Study on viral pathogens for infant diarrhea in Chizhou, Anhui / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To understand the major viral pathogens for infant diarrhea in Chizhou, Anhui.</p><p><b>METHODS</b>Fecal specimens were collected from 428 infants hospitalized with diarrhea in People's Hospital of Chizhou, Anhui between January 2005 and December 2006. Enzyme immunoassay (EIA) and enzyme-linked immunosorbent assay (ELISA) were performed to detected specific antigens of rotavirus, astrovirus, adenovirus or calicivirus. For rotavirus, specimens were tested for typing by serum virology and reverse transcription PCR (RT-PCR).</p><p><b>RESULTS</b>The positive test rates for rotavirus, calicivirus and adenovirus were 29.2%, 10.5% and 2.4%, respectively, in infants with diarrhea from Chizhou, Anhui. Among them, 3 cases (2.4%) were infected with two or more viruses. Forty-four fecal specimens were tested with ELISA and RT-PCR for rotavirus, and the results showed that the two methods got consistency of 97.7%. Another 48 rotaviruses of serotype G were further typed as serotype I (3 cases), II (1 case), III (35 cases) and IX (2 cases), with 7 cases untyped. Among the cases that could be typed, 26 cases were collected from 2005, and 15 from 2006. RV type ml was the major pathogens for infant diarrhea, with 24 from 2005 and 11 from 2006. Among the 8 rotaviruses of type P, 7 were type as G3P8 and one G9P8. The epidemic of rotavirus showed significant season privilege, with a high prevalence in winter-spring, while the prevalence of calicivirus was prone to be high in Fall.</p><p><b>CONCLUSION</b>Rotavirus was the major viral pathogen accounting for infant diarrhea in Chizhou, Anhui, followed by calicivirus and adenovirus Type G3 was the main rotavirus, especially type G3P8.</p>

Caracterización molecular de calicivirus aislados de brotes de gastroenteritis ocurridos en la Argentina durante los años 2005 y 2006 / Molecular characterization of calicivirus strains detected in outbreaks of gastroenteritis occurring in Argentina during 2005 and 2006

Con el objetivo de determinar la incidencia de calicivirus, rotavirus y astrovirus en brotes de gastroenteritis ocurridos en diversas regiones de la Argentina durante los años 2005 y 2006, se analizaron muestras de materia fecal provenientes de 7 brotes con resultado de coprocultivo negativo. Para el diagnóstico de rotavirus se utilizó un ELISA comercial, mientras que para el diagnóstico de calicivirus y astrovirus se utilizó el método de RT-PCR. De las 74 muestras analizadas, 20 fueron positivas para calicivirus, 17 para rotavirus y una para astrovirus. No se identificaron infecciones virales mixtas. En 5 muestras positivas para calicivirus se secuenció una región del gen de la polimerasa; 4 de ellas correspondieron al género Norovirus y una al género Sapovirus. El análisis filogenético de las muestras secuenciadas determinó la presencia de norovirus de los genogrupos GI y GII; dentro de este último, se identificaron los genotipos GII-4, GII-b y GII-17. El análisis de la muestra en la cual se identificó sapovirus reveló la presencia del genotipo GI-1. Este estudio representa una continuación del análisis epidemiológico molecular de calicivirus asociados a brotes de gastroenteritis iniciado en 2004 y constituye la primera comunicación de la circulación de norovirus del genotipo GII-17 en la Argentina.

In order to determine the incidence of calicivirus, rotavirus and astrovirus in outbreaks of gastroenteritis occurring in different regions of Argentina during 2005 and 2006, fecal samples from seven nonbacterial outbreaks were analyzed. A commercial ELISA was used for rotavirus detection, while RT-PCRs were used for calicivirus and astrovirus. Of the 74 samples analyzed, 20 were calicivirus positive, 17 were rotavirus positive and one was astrovirus positive. No mixed infections were detected. A partial region of the RdRp gene was sequenced in five calicivirus positive-samples; 4 of them belonged to Norovirus genus and one to Sapovirus genus. The phylogenetic analysis of norovirus-positive-samples revealed the presence of strains from genogroups GI and GII; genotypes GII- 4, GII-b and GII-17 were identified within the latter. Phylogenetic the sapovirus-positive-sample revealed the presence of genotype GI-1. This study represents a follow-up of the of molecular epidemiology analysis of calicivirus associated to gastroenteritis outbreaks that have been carried out by our group since 2004, and constitutes the first report of the circulation of genotype GII-17 in Argentina.

Adenovirus, calicivirus and astrovirus detection in fecal samples of hospitalized children with acute gastroenteritis from Campo Grande, MS, Brazil

We analyzed fecal samples from hospitalized children up to three years of age with acute gastroenteritis at Campo Grande, Mato Grosso do Sul, Brazil, from May 2000-January 2004. Astrovirus and calicivirus were detected by Reverse Transcription-Polymerase Chain Reaction and adenovirus was detected using the Rotavirus and Adenovirus combined immunoenzyme assay. Astrovirus, adenovirus and calicivirus were detected at rates of 3.1 percent, 3.6 percent and 7.6 percent, respectively. These results re-emphasize the need for the establishment of regional vigilance systems to evaluate the impact of enteric viruses on viral gastroenteritis.

Detection and phylogenetic analysis of porcine enteric calicivirus, genetically related to the Cowden strain of sapovirus genogroup III, in Brazilian swine herds

Sapovirus of the Caliciviridae family is an important agent of acute gastroenteritis in children and piglets. The Sapovirus genus is divided into seven genogroups (G), and strains from the GIII, GVI and GVII are associated with infections in swine. Despite the high prevalence in some countries, there are no studies related to the presence of porcine enteric sapovirus infections in piglets in Brazil. In the present study, 18 fecal specimens from piglets up to 28 days were examined to determine the presence of sapovirus genome by RT-PCR assay, using primers designed to amplify a 331 bp segment of the RNA polymerase gene. In 44.4 percent (8/18) of fecal samples, an amplified DNA fragment was obtained. One of these fragments was sequenced and submitted to molecular and phylogenetic analysis. This analysis revealed high similarity, with nucleotides (87 percent) and amino acids (97.8 percent), to the Cowden strain, the GIII prototype of porcine enteric calicivirus. This is the first description of sapovirus in Brazilian swine herds.

O sapovírus classificado na família Caliciviridae é um importante causador de gastroenterite aguda em crianças e leitões. O gênero Sapovirus é dividido em sete genogrupos (G), sendo que as estirpes dos GIII, GVI e GVII estão associadas com infecção em suínos. Apesar da alta prevalência da infecção em alguns países, ainda não existem estudos referentes à presença do calicivírus entérico suíno nos rebanhos brasileiros. No presente estudo 18 amostras de fezes de leitões com até 28 dias foram avaliadas pela RT-PCR para a presença do genoma do sapovírus, utilizando os primers desenvolvidos para amplificar um segmento de 331 pb do gene da RNA polimerase viral. Em 44,4 por cento (8/18) das amostras foi amplificado um fragmento de DNA. Um desses amplicons foi seqüenciado e pela análise molecular e filogenética foi verificada similaridade de 87 por cento em nucleotídeos e 97,8 por cento em aminoácidos com a estirpe Cowden, protótipo do GIII. Esta é a primeira descrição do sapovírus em rebanhos suínos brasileiros.

Purification of Protein Expressed from Three Different Regions of Norovirus (NoV)

Norovirus (NoV), which belongs to the family Caliciviridae, is one of the major causes of nonbacterial acute gastroenteritis in the world. In this study, we purified proteins from the epitope region of norovirus for development of the rapid diagnosis system using polyclonal antibodies. As antigens, parts of the ORF (open reading frame) 2, ORF2-P domain, ORF2-Epi, and ORF3 regions were selected and their expressions were induced. The antigenicity of the purified proteins was identified by Western blotting. Each of the purified proteins was injected into mice for the production of novel antibodies and after 3 months of immunization, sera from the mice were obtained. The polyclonal antibody titer was tested by enzyme-linked immunosorbent assay (ELISA) and antibody against ORF2-Epi showed the highest titer. Those polyclonal antibodies can be used in further immunoassay for the rapid detection of NoVs from food and clinical specimens.

Prevalence of feline herpesvirus 1, feline calicivirus and Chlamydophila felis in clinically normal cats at a Korean animal shelter

The prevalence of feline herpesvirus-1 (FHV-1), feline calicivirus (FCV), and Chlamydophila (C.) felis was studied in cats of an animal shelter in Korea. Total 78 cats without ocular and upper respiratory tract disease were examined. Specimens were obtained from ocular conjunctiva and oropharynx. Using multiplex polymerase chain reaction (PCR) and reverse transcription PCR, three pathogens were simultaneously detected. In examined 78 cats, 49 (63%) cats were positive for FHV-1. However, all specimens were negative for C. felis and FCV. In conclusion, many cats recovered from FHV-1 infection remain subclinical carriers in shelter environment.

Epidemiological investigation of an outbreak of acute gastroenteritis caused by human calicivirus in Lulong County / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To survey an outbreak of acute gastroenteritis in Lulong County and analyze the cause of the disease.</p><p><b>METHODS</b>Epidemiological methods were applied to investigate an outbreak of acute gastroenteritis occurred in June 2000 in Lulong County. Stool specimens were collected from diarrhea patients and were tested for human calicivirus by ELISA and RT-PCR. The products of RT-PCR were cloned and sequenced, then phylogenetic analysis was carried out.</p><p><b>RESULTS</b>In total, 736 farmers were surveyed, among them 134 had acute gastroenteritis, the attack rate was 18.20%, and one elderly patient died. The age of patients was from 1 to 77 years and the incidence of the disease among young people was higher with a peak in June 25 through 30. Six stool specimens were tested for caliciviruses by ELISA and 3 were positives, one of them was confirmed by RT-PCR and belonged to norovirus genotype GI/2. No other pathogens were detected.</p><p><b>CONCLUSION</b>Human calicivirus was confirmed to be the cause of the outbreak of acute gastroenteritis.</p>

Investigation of human calicivirus (HuCV) diarrhea among infantile and young children in China, 1999--2005 / 病毒学报

Human calicivirus (HuCV) has been well known as an important pathogen of outbreak and sporadic acute nonbacterial gastroenteritis worldwide. To investigate epidemiological feature and genetic diversity of HuCV among children in China, fecal specimens were collected from children under 5 years of age with acute diarrhea at 13 hospitals in different provinces across China. The study was performed year-round from January 1999 to June 2005. Fecal specimens were tested for bacteria and rotavirus first and the negative specimens then were tested for HuCV using ELISA and RT-PCR. PCR amplicons were cloned and sequenced for strain characterization. A total of 4426 rotavirus- negative fecal samples were screened. From these, 840 (19%) were positive for HuCV by either or both ELISA (14%) and RT-PCR (9.6%). HuCV infection occurred year-round with an epidemic in each winter (October-January) and mainly in children at 6 -- 17 months of age. Of 151 HuCV strains characterized, 146 belong to norovirus (NV, 96.7%) and 5 were sapoviruses (SV). Among norovirus strains, genotype GG II/4 was most common (99/146), followed by GG II/3 (22/146), GG II/5 (8/146), and 2 strains of each of GG II/6, GG II/7, GG II/8, and GG I/2, the other 9 strains of NV GG II were unique, potentially belonging to new genotypes. These results plus the epidemiology data suggested that HuCVs are an important cause of severe diarrhea in Chinese children that were under reported due to a lack of a simple diagnostic assay. The finding of the potential new genotypes indicates that the current assays need to be improved for broader detection and besides, a continual surveillance for better understanding the epidemiology the disease burden and the searching for new strains of HuCVs is necessary.

Detection of calicivirus from fecal samples from children with acute gastroenteritis in the West Central region of Brazil

The objective of this study was to describe the circulation of caliciviruses in the West Central region of Brazil and its correlation with children's gender and age, as well as with the year and months of the sample collection. Reverse transcriptase-polymerase chain reaction was performed to detect the human calicivirus genome in 1006 fecal samples that were collected in Goiânia (n = 696) and Brasília (n = 310). Viral RNA was detected in 8.6 percent of the samples. No significant difference in viral prevalence was found regarding gender, age or year of the sample. However, it was observed that in Goiânia, there is a higher incidence of caliciviruses from September to March. The analysis employing three primer pairs demonstrated that the Ni/E3 or JV12/13 primer pairs, which detect norovirus (NoV), detected 41 positive samples while the 289/290 primer pair, which detects NoV or sapovirus, detected the remaining 46 samples. Calicivirus circulates in the West Central region of Brazil and for better detection of this virus it is important to use more than one primer pair. Also, we conclude that the seasonality presented by this virus is related to higher humidity in the period.