Caliciviridae Infections ; epidemiology ; virology ; Gastroenteritis ; virology ; Genetic Variation ; Genotype ; Humans ; Norovirus ; classification ; genetics

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.
Animals ; Caliciviridae/genetics ; Caliciviridae Infections/epidemiology/*veterinary ; Cat Diseases/*epidemiology/*microbiology/*virology ; Cats ; Chlamydophila/genetics ; Chlamydophila Infections/epidemiology/*veterinary ; DNA Primers/genetics ; Herpesviridae/genetics ; Herpesviridae Infections/epidemiology/*veterinary ; Housing, Animal ; Korea/epidemiology ; Prevalence ; Reverse Transcriptase Polymerase Chain Reaction

Caliciviridae Infections ; epidemiology ; genetics ; virology ; China ; epidemiology ; Gastroenteritis ; virology ; Humans ; Molecular Epidemiology ; Norovirus ; genetics ; RNA, Viral ; isolation & purification

OBJECTIVETo understand the characteristics of human calicivirus (HuCV) infection in infants with diarrhea in Guangzhou city and to study genotype of the virus.

METHODSThe authors collected fecal specimens from 22 children with acute nonbacterial gastroenteritis from November to December, 2001. HuCV was detected from the specimens by RT-PCR. The PCR products were cloned into the PMD18-T cloning vector and sequenced.

RESULTSHCV was detected from the specimens of 2 cases (9%, 2/22). The nucleotide sequence analysis revealed that the virus strains belonged to genotype 2 of Norwalk-like viruses.

CONCLUSIONHuCV is one of the pathogens causing diarrhea in infants and young children in Guangzhou area. HuCV infection occurred sporadically in autumn and winter.

Base Sequence ; Caliciviridae ; genetics ; Caliciviridae Infections ; complications ; virology ; China ; DNA, Viral ; chemistry ; genetics ; Diarrhea, Infantile ; etiology ; Dysentery ; etiology ; Feces ; virology ; Genotype ; Humans ; Infant ; Molecular Sequence Data ; Phylogeny ; Reverse Transcriptase Polymerase Chain Reaction ; Sequence Analysis, DNA ; Sequence Homology, Nucleic Acid

OBJECTIVETo survey an outbreak of acute gastroenteritis in Lulong County and analyze the cause of the disease.

METHODSEpidemiological 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.

RESULTSIn 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.

CONCLUSIONHuman calicivirus was confirmed to be the cause of the outbreak of acute gastroenteritis.

Acute Disease ; Caliciviridae ; genetics ; isolation & purification ; Caliciviridae Infections ; epidemiology ; China ; epidemiology ; Disease Outbreaks ; Enzyme-Linked Immunosorbent Assay ; Feces ; virology ; Gastroenteritis ; epidemiology ; virology ; Humans ; RNA, Viral ; genetics ; Reverse Transcriptase Polymerase Chain Reaction

OBJECTIVETo investigate the characteristics of human caliciviruses (HuCV) diarrhea among infants and young children with acute diarrhea in Lanzhou, Gansu Province, China by using molecular epidemiologic techniques.

METHODSStool specimens were collected from both outpatients and inpatients with acute diarrhea in Lanzhou. Enzyme-linked immunosorbant assay (ELISA) was used to detect rotavirus antigen (RVA). Reverse transcription-polymerase chain reactions (RT-PCR) were used to detect HuCV in stool specimens of RV ELISA (-).

RESULTSOf the stool specimens collected from 515 cases in Lanzhou from December 2001 to June 2004, 264 were RVA ELISA (+) and 251 were RVA ELISA (-). Among all cases who were RVA ELISA (-), 25 (9.96%) were found positive for HuCV. HuCV was detected in 12 of 133 cases (9.02%) from December 2001 to November 2002, no genotyping was performed for these cases. From July 2003 to June 2004 13 of 118 cases (11.02%) were found positive for HuCV, of whom 11 cases had Norwalk-like virus GII (NLV GII) infection and 2 cases had Sapporo-like virus infection (one case had combined infection with astrovirus) and no NLV GI was found. HuCV infection mainly occurred in children under 2 years of age and no seasonal cluster was found.

CONCLUSIONHuCV is one of the major etiological agents of viral diarrhea among infants and young children in Lanzhou. NLV GII maybe the predominant genotype.

Caliciviridae ; genetics ; Caliciviridae Infections ; epidemiology ; Child, Preschool ; China ; epidemiology ; Diarrhea ; epidemiology ; virology ; Enzyme-Linked Immunosorbent Assay ; Feces ; virology ; Genotype ; Humans ; Infant ; Molecular Epidemiology ; RNA, Viral ; genetics ; Reverse Transcriptase Polymerase Chain Reaction

Noroviruses (NoVs) are one of the most important foodborne viral pathogens worldwide. Shellfish are the most common carriers of NoVs as they can concentrate and accumulate large amounts of the virus through filter feeding from seawater. Shellfish may selectively accumulate NoVs with different genotypes, and this bioaccumulation may depend on the season and location. Our previous studies found various histo-blood group antigens (HBGAs) in shellfish tissues. While HBGAs might be the main reason that NoVs are accumulated in shellfish, the detailed mechanism behind NoV concentration and bioaccumulation in shellfish is not clear. Here we review current research into NoV bioaccumulation, tissue distribution, seasonal variation, and binding mechanism in shellfish. This paper may provide insight into controlling NoV transmission and decreasing the risks associated with shellfish consumption.
Animals ; Caliciviridae Infections ; transmission ; virology ; Food Contamination ; analysis ; Foodborne Diseases ; virology ; Humans ; Norovirus ; classification ; genetics ; isolation & purification ; physiology ; Shellfish ; virology

A simple, rapid and sensitive colorimetric reverse transcription loop-mediated isothermal amplification (RT-LAMP) method was established to detect norovirus genotype GII. The method employed a set of six specially designed primers that recognized eight distinct sequences of RNA-dependant RNA polymerase and capsid protein gene for amplification of nucleic acid under isothermal conditions at 65 degrees C for 60 minutes. The amplification process of RT-LAMP was monitored by the addition of HNB (Hydroxy naphthol blue) dye prior to amplification. A positive reaction was indicated by a color change from violet to sky blue and confirmed by agarose electrophoresis. The specificity of the RT-LAMP was validated by detecting several different diarrhea viruses including norovirus genotype GII. The sensitivity was determined by serial dilutions of RNA molecules from in vitro transcription of norovirus genotype GII in parallel with conventional RT-PCR detection. The assay was further evaluated with 93 clinical specimens of diarrhea patients. The results showed that the sensitivity of RT-LAMP was 1 000 copies/microL with a high specificity and the relative sensitivity was at the same level as that of conventional RT-PCR. Positive rate of RT-LAMP in analysis of clinical specimens was approximately the same as that of conventional RT-PCR as well. This colorimetric RT-LAMP assay was potential for rapid detection of norovirus genotype GII on spot due to the observation of visual result with high specificity and sensitivity, time-saving and cost benefit.
Caliciviridae Infections ; diagnosis ; virology ; Colorimetry ; methods ; Feces ; virology ; Genotype ; Humans ; Norovirus ; genetics ; isolation & purification ; Nucleic Acid Amplification Techniques ; methods

Rabbit haemorrhagic disease virus (RHDV) and myxoma virus (MYXV), are two pathogens that have harmful effect on rabbit breeding and population decline of European rabbits in their native range, causing rabbit haemorrhagic disease (rabbit fever) and myxomatosis, respectively. The capsid protein VP60 of the RHDV represents the major antigenic protein. To develop a recombinant bivalent vaccine candidate that can simultaneously prevent these two diseases, we used the nonessential gene TK (thymidine kinase) of MYXV as the insertion site to construct a recombinant shuttle vector p7.5-VP60-GFP expressing the RHDV major capsid protein (VP60) and the selectable marker GFP. Then the shuttle vector p7.5-VP60-GFP was transfected into rabbit kidney cell line RK13 which was previously infected with MYXV. After homologous recombination, the recombinant virus expressing GFP was screened under a fluorescence microscope and named as rMV-VP60-GFP. Finally, the specific gene-knock in and expression verification of the vp60 and gfp genes of the recombinant virus was confirmed by PCR and Western blotting. The results showed that these two genes were readily knocked into the MYXV genome and also successfully expressed, indicating that the recombinant MYXV expressing the vp60 of RHDV was generated. Protection against MYXV challenge showed that the recombinant virus induced detectable antibodies against MYXV which would shed light on development of the effective vaccine.
Animals ; Blotting, Western ; Caliciviridae Infections/veterinary* ; Hemorrhagic Disease Virus, Rabbit/immunology* ; Rabbits ; Vaccines, Synthetic/immunology* ; Viral Structural Proteins/genetics*

OBJECTIVETo investigate the epidemiological characteristus of human caliciviruses (HuCVs) among children under 5 years of age with acute diarrhea and to estimate the disease burden in Lulong county.

METHODSHuCVs were detected by enzyme linked immunosorbent assay (ELISA) and reverse transcription-polymerase chain reaction (RT-PCR). Some PCR amplicons were cloned and sequenced. Phylogenetic tree was constructed for strain characterization. The rate of HuCVs-attributed hospitalization was estimated according to the positive rate of HuCVs detection in fecal specimens collected from hospitalized diarrhea patients.

RESULTSBetween July 1999 and June 2001, 708 fecal specimens were collected, of which 393 rotavirus-negative and 5 rotavirus-positive specimens were detected for HuCVs. Thirty-one point six percentage of fecal specimens from patients with diarrhea was HuCVs positive. Among inpatients, HuCVs positive rate was 17.5%. HuCVs detection was mainly distributed in 3 - 17 mouth-old children, in winter. All 11 strains belonged to NLV GII in which 6 strains GII-3, 2 strains GII-4 and 3 strains GII-7, and they shared 55.1% - 100% nucleotide identity. NLV GII-4 and GII-7 were identified in 2000, while NLV GII-3 and GII-7 in 2001. The preliminary estimate of HuCVs-attributed hospitalization rate was 3.6 per thousand.

CONCLUSIONHuman caliciviruses with different genotypes circulated among children in Lulong county with GII NLVs were the prevalent strains. The disease burden of HuCVs was second to rotavirus.

Acute Disease ; Age Factors ; Caliciviridae ; genetics ; immunology ; Caliciviridae Infections ; complications ; epidemiology ; Child, Preschool ; China ; epidemiology ; Dysentery ; epidemiology ; etiology ; Enzyme-Linked Immunosorbent Assay ; Humans ; Infant ; Inpatients ; statistics & numerical data ; Phylogeny ; Reverse Transcriptase Polymerase Chain Reaction ; Seasons