Detection and genotyping of enteroviruses in 3 960 influenza-negativeinfluenza-like illness cases in Chongqing / 公共卫生与预防医学

Objective To understand the epidemiological characteristics and genotype distribution of enterovirus (EV) in influenza-negative influenza-like illness (ILI) cases in Chongqing, and to provide a scientific basis for EV prevention and control. Methods Throat swab samples of influenza-negative ILI cases were collected from surveillance sites. The samples were detected for EV using real-time RT-PCR. The VP4 regions of positive samples were amplified and sequenced for genotyping. Results A total of 3 960 influenza-negative ILI samples were collected from January to December 2021, and 316 (7.98%) of them were EV-positive. EV could be detected in influenza-negative ILI cases in Chongqing all year round. The months with high EV-positive rates were January (11.60%), April (10.56%), May (11.79%), June (12.62%), and July (10.33%). There was a statistically significant difference in the detection rate of EV in ILI cases in different regions, gender, and age groups (χ2=29.647，χ2=4.192，χ2=69.176，P<0.05). A total of 213 EV-positive cases were successfully genotyped, including 17 genotypes of EV-A, EV-B, and EV-C and 5 genotypes of HRV-B. The dominant genotypes were CV-A4 (32.86%), CV-A2 (23.00%), CA-6 (12.21%), and CA-10 (11.74%). EV-D and novel EV were not identified in this study. Conclusion EV is an important pathogen in ILI cases in Chongqing. The prevalence of EV in ILI cases in Chongqing has typical regional, seasonal and population characteristics. Prevention and control should be carried out in Chongqing according to the epidemic characteristics of EV.

Serotype detection and phylogenetic analysis of coxsackievirus A2 causing hand, foot and mouth disease in Yunnan Province in 2021 / 中华微生物学和免疫学杂志

Objective:To analyze the non-enterovirus A71 (non-EVA71) and non-coxsackievirus A16 (non-CVA16) enteroviruses causing hand, foot and mouth disease (HFMD) in Kunming and Qujing of Yunnan Province in 2021 by sequencing the VP4/VP2 and VP1 genes and to analyze the phylogenetic characteristics of the VP1 gene of CVA2, aiming to provide reference for the prevention and control of CVA2.Methods:The samples were made and extracted strictly according to the Laboratory Manual for Hand, Foot and Mouth Disease (China Center for Disease Control and Prevention, 2018 Edition). VP4/VP2 junction regions were firstly amplified and sequenced by MD91/OL68-1 primers. These sequences were firstly edited and then "blasted" on the GenBank to determine the virus serotype. To analyze the phylogenetic characteristics of CVA2, the entire VP1 gene sequences were amplified in two segments using enterovirus species A primers. Virus serotype was again confirmed online by "Enterovirus Genotyping Tool Version 0.1". The sequences of the reference virus genotypes/sub-genotypes were downloaded according to the reference. The phylogenetic trees were constructed by Mega5.2 software and the genetic characteristics were analyzed.Results:A total of 749 non-EVA71 and non-CVA16 enteroviruses were detected in the two areas in 2021. Group A enteroviruses were the main pathogens, with CVA16 as the predominant virus, and a small number of group B enteroviruses were reported. Only five strains of CVA2 were detected with a detection rate of 0.67% (5/749), indicating that CVA2 was a rare pathogen for HFMD in the two areas. The sequencing and serotyping results were consistent using the two genomic regions of VP4/VP2 junction region and VP1 region. Phylogenetic analysis showed that three Kunming strains belonged to genotype A, while two Qujing strains belonged to genotype D.Conclusions:The detection rate of CVA2 in Kunming and Qujing was 0.67% in 2021. CVA2 was a rare pathogen for HFMD in the two regions. Phylogenetic analysis showed genotypes A and D spread in Kunming and Qujing, respectively, but had not caused epidemics. To our knowledge, this was the first report of genotype A of CVA2 in China. Strengthening the laboratory surveillance especially molecular epidemiological surveillance is valuable for the monitor and analysis of transmission source for CVA2.

Genotyping and identification of non-polio enterovirus isolates from acute flaccid paralysis cases in Chongqing in 2013-2020 / 公共卫生与预防医学

Objective To classify and identify the 53 strains of non-polio enterovirus (NPEV) isolated from acute flaccid paralysis (AFP) cases in Chongqing from 2013 to 2020, and to investigate the genotype distribution of the strains. Methods Commercial real-time fluorescence quantitative polymerase chain reaction (real-time PCR) reagents were used for rapid identification of the strains. The nucleotide sequences of VP1 and VP4 regions were used for genotyping. Results Fifty enteroviruses were identified, 33 (66%) in group A and 17 (34%) in group B. Group C and D enteroviruses were not found in these strains，and 3 strains could not be identified. In this study, EV-A71 was the dominant type, with 11 strains (22%), but EV-A71 strain was not isolated since 2016. The sequences of VP4 region and VP1 region were completely consistent in enterovirus grouping. Conclusion When using commercial real-time PCR reagents for enterovirus typing, the identification results of high CT values may be inaccurate. In the genotyping of enterovirus, the nucleotide sequence of VP4 region is first used for grouping, and then the nucleotide sequence of VP1 region is used for genotyping, which could simplify the experimental process. NPEV isolates from AFP cases in Chongqing showed poor genotype diversity. In order to enrich and improve the enterovirus gene database in Chongqing, it is necessary to carry out research on enterovirus transmitted by respiratory tract.

Serologic and molecular characterization of rotavirus from children with acute gastroenteritis in Chennai, Tamil Nadu, India

Background: Rotavirus gastroenteritis is the leading cause of diarrhea in infants and young children worldwide. Although, Rotavirus vaccine has been introduced in 2017 in states like Tamil Nadu, there are reports of the role of Rotavirus as one of high disease burden agents with genetic variants arising, especially from low-income countries like India.Methods: Authors evaluated stool samples from 507 children with acute gastroenteritis Rotavirus A among the hospitalized children (>5 years) to provide baseline information on changing profile in this state. The stool samples were collected and screened for Rotaviral Antigen by Enzyme Immuno Assay and use of semi-multiplex RT PCR technique was conceded out in order to conclude the P and G genotypes of human rotavirus in rotavirus-positive samples from January 2014 to December 2016 in and around Chennai, India.Results: Of 507 samples collected 213 (42.01%) were positive for rotavirus antigen by Enzyme Immuno Assay (EIA). The maximum positivity (75%) was in the age group of one to two years. Rotavirus positives were subjected to further VP7 and VP4 molecular characterization and the predominant genotypes identified were G9P[4] followed by G9P[8], G1P[8], G3P[8], G2P[4] and mixed types of G2G9 with P[4] and G4P[6][11] with few untypable strains.Conclusions: This study had demonstrated the Rota Virus Gastro Enteritis (RVGE) is a common disease affecting the pediatric population and G9P[4], G9P[8] circulating types among the gastroenteritis cases reported in the city and its suburban area. This study in comparison to previous ones shows that the dominant serotypes and circulating genotypes changes from time to time within country. The results have reemphasized the need of rotavirus vaccines with broad serotype coverage which may help in decreasing the disease burden in this region of the country.

Etiology analysis of hand, foot and mouth disease cases and genetic characteristics of coxsackievirus A6 in six prefectures/cities of Yunnan Province in 2018 / 中华微生物学和免疫学杂志

Objective To detect the enterovirus VP4 and VP1 genes in 510 stool samples collect-ed from hand, foot and mouth disease ( HFMD) cases and analyze the phylogenetic characteristics of the en-tire VP1 genes of coxsackievirus A6 (CV-A6) strains in six prefectures/cities of Yunnan Province in 2018. Methods Viral RNA was abstracted from the stool samples. VP4 gene sequences were amplified by RT-PCR and sequenced using the MD91/OL68-1 primer pair to identify viral genotypes. Whole VP1 gene se-quences were amplified and sequenced using appropriate primer pairs. The whole VP1 gene sequences of CV-A6 reference strains were downloaded from GenBank. MEGA5. 2 software was used to analyze the simi-larity in nucleotide and amino acid sequences between different strains and phylogenetic tree was constructed for analysis of genetic characteristics and molecular epidemiology. Results VP4 and VP1 gene sequences were obtained from 57 out of 510 stool samples with a positive rate of 11. 17％ (57/510). There were 43 CV-A6 (8. 43％, 43/510), six CV-A10 (1. 17％, 6/510), two enterovirus A71 (EV-A71, 0. 39％, 2/510) and two CV-A9 (0. 39％, 2/510) strains. The other four strains were CV-A4 (0. 19％, 1/510), CV-A5 (0. 19％, 1/510), CV-B1 (0. 19％, 1/510) and E11 (0. 19％, 1/510). The phylogenetic analy-sis showed that all 43 CV-A6 strains belonged to sub-genotype D3. Conclusions In the 510 HFMD sam-ples, CV-A6 strains were mostly detected with a detection rate of 8. 43％ and accounted for 75. 44％ (43/57) of all isolates, followed by CV-A10 (1. 17％, 6/510) and EV-A71 (0. 39％, 2/510). There was a large HFMD outbreak mainly caused by CV-A6 in Yunnan Province in 2018. The outbreak was caused by CV-A6 of sub-genotype D3, as was the case with pervious outbreaks in China.

Etiology analysis of hand, foot and mouth disease cases and genetic characteristics of coxsackievirus A6 in six prefectures/cities of Yunnan Province in 2018 / 中华微生物学和免疫学杂志

Objective@#To detect the enterovirus VP4 and VP1 genes in 510 stool samples collected from hand, foot and mouth disease (HFMD) cases and analyze the phylogenetic characteristics of the entire VP1 genes of coxsackievirus A6 (CV-A6) strains in six prefectures/cities of Yunnan Province in 2018.@*Methods@#Viral RNA was abstracted from the stool samples. VP4 gene sequences were amplified by RT-PCR and sequenced using the MD91/OL68-1 primer pair to identify viral genotypes. Whole VP1 gene sequences were amplified and sequenced using appropriate primer pairs. The whole VP1 gene sequences of CV-A6 reference strains were downloaded from GenBank. MEGA5.2 software was used to analyze the similarity in nucleotide and amino acid sequences between different strains and phylogenetic tree was constructed for analysis of genetic characteristics and molecular epidemiology.@*Results@#VP4 and VP1 gene sequences were obtained from 57 out of 510 stool samples with a positive rate of 11.17% (57/510). There were 43 CV-A6 (8.43%, 43/510), six CV-A10 (1.17%, 6/510), two enterovirus A71 (EV-A71, 0.39%, 2/510) and two CV-A9 (0.39%, 2/510) strains. The other four strains were CV-A4 (0.19%, 1/510), CV-A5 (0.19%, 1/510), CV-B1 (0.19%, 1/510) and E11 (0.19%, 1/510). The phylogenetic analysis showed that all 43 CV-A6 strains belonged to sub-genotype D3.@*Conclusions@#In the 510 HFMD samples, CV-A6 strains were mostly detected with a detection rate of 8.43% and accounted for 75.44% (43/57) of all isolates, followed by CV-A10 (1.17%, 6/510) and EV-A71 (0.39%, 2/510). There was a large HFMD outbreak mainly caused by CV-A6 in Yunnan Province in 2018. The outbreak was caused by CV-A6 of sub-genotype D3, as was the case with pervious outbreaks in China.

Polymerization and evaluation of the protective efficacy of rotavirus VP4* proteins / 生物工程学报

In previous studies, we found that truncated rotavirus VP4* (aa 26-476) could be expressed in soluble form in Escherichia coli and confer high protection against rotavirus in the mouse mode. In this study, we further improved the immunogenicity of VP4* by polymerization. The purified VP4* was polymerized through incubation at 37 ℃ for 24 h, and then the homogeneity of the particles was analyzed by HPLC, TEM and AUC, while the thermal stability and antigenicity was analyzed by DSC and ELISA, respectively. Finally, the immunogenicity and protective efficacy of the polymers analyzed by a mouse maternal antibody model. The results showed that VP4* aggregated into homogeneous polymers, with high thermostability and neutralizing antibody binding activity. In addition, VP4* polymers (endotoxin <20 EU/dose) stimulated higher neutralizing antibodies and confer higher protection against rotavirus-induced diarrhoea compared with the VP4* trimers when immunized with aluminium adjuvant. In summary, the study in VP4* polymers provides a new strategy for the development of recombinant rotavirus vaccines.

Research progress in rotavirus VP4 subunit vaccine / 生物工程学报

Rotaviruses are leading causes of worldwide acute diarrhea in children younger than 5 years old, with severe consequence of social and economic burden. Vaccination is the most effective way to control rotavirus infection, however, the licensed rotavirus vaccines are ineffective in some low-income countries of Africa and Asia, where the mortality caused by rotavirus is higher than other areas. In addition, there are also safety concerns such as increased risk of intussusception. Therefore, it is urgent to improve the efficiency and safety of rotavirus vaccine to reduce the morbidity and mortality caused by rotavirus. Till now, many efforts are made to improve the effectiveness of rotavirus vaccines, and the inactive vaccine becomes the main trend in the research of rotavirus vaccine. The developments in recombinant rotavirus vaccines, especially in VP4 subunit vaccines are summarized in this review, and it could be helpful to develop effective recombinant rotavirus vaccines in further studies.

Análisis filogenético y de presión evolutiva de secuencias nucleotídicas del gen VP4 de especies de enterovirus humanos / Phylogenetic and evolutive pressure analyses of nucleotide sequences of VP4 gene of human enterovirus species

El género Enterovirus es un grupo viral que afecta a un amplio rango de hospederos, entre ellos los humanos (especies A, B, C, y D), causan enfermedades respiratorias, gastrointestinales, neurológicas, y otras, y son altamente contagiosos. Los síntomas pueden ser leves o graves. El objetivo del trabajo fue analizar la variación nucleotídica, filogenética y de presión evolutiva de secuencias nucleotídicas del gen VP4 de las cuatro especies que afectan a los humanos. Se emplearon 92 secuencias nucleotídicas disponibles en la base de datos GenBank; éstas se editaron con el software BioEdit y se alinearon con Clustal W; las relaciones filogenéticas se determinaron con MEGA6, y las presiones evolutivas con los algoritmos SNAP y SLAC. Se encontró que la identidad nucleotídica mínima intra-especie fue de 43,2% (especie B) a 72,6% (especie D). Los genotipos más variables por especie fueron EV-71 (A), Echovirus 2 (B), EV-118 (C), y EV-94 (D). El análisis de presión evolutiva mostró que el gen VP4 en las cuatro especies evoluciona bajo presión selectiva negativa. Esto indicaría que la alta tasa mutacional y eventos de recombinación no tienen un rol significativo en la evolución de este gen, debido probablemente a la localización interna de la proteína VP4.

The Enterovirus genus is a viral group that affects a wide host range, including humans (species A, B, C and D), cause respiratory, gastrointestinal, and neurologic disease, amongothers, and are highly contagious. The symptoms range from mild to severe. The objectiveof this study was to perform a nucleotidic variation, phylogenetic and selective pressureanalyses of the VP4 gene from the four enterovirus species that affect humans. Ninety-twonucleotide sequences (available in the GenBank database) were employed; they were edited with Bio Edit software and aligned with Clustal W; the phylogenetic relationships weredetermined with MEGA6, and the evolutive pressures with SNAP and SLAC algorithms. Itwas found an intra-species nucleotide identity of at least 43,2% (species B) to 72,6% (species D). The more variable genotypes by species were EV-71 (A), Echovirus 2 (B), EV-118 (C), and EV-94 (D). The selective pressure analysis showed that VP4 gene of the fourspecies evolves by negative pressure. This would indicate that the high mutation rate andrecombination events do not have a significant role in the evolution of this gene, probablydue to the internal localization of the VP4 protein.

Molecular characterisation of the NSP4 gene of group A human rotavirus G2P[4] strains circulating in São Paulo, Brazil, from 1994 and 2006 to 2010

Group A human rotaviruses (HuRVA) are causative agents of acute gastroenteritis. Six viral structural proteins (VPs) and six nonstructural proteins (NSPs) are produced in RV-infected cells. NSP4 is a diarrhoea-inducing viral enterotoxin and NSP4 gene analysis revealed at least 15 (E1-E15) genotypes. This study analysed the NSP4 genetic diversity of HuRVA G2P[4] strains collected in the state of São Paulo (SP) from 1994 and 2006-2010 using reverse transcription-polymerase chain reaction, sequencing and phylogenetic analysis. Forty (97.6%) G2P[4] strains displayed genotype E2; one strain (2.4%) displayed genotype E1. These results are consistent with the proposed linkage between VP4/VP7 (G2P[4]) and the NSP4 (E2) genotype of HuRVA. NSP4 phylogenetic analysis showed distinct clusters, with grouping of most strains by their genotype and collection year, and most strains from SP were clustered together with strains from other Brazilian states. A deduced amino acid sequence alignment for E2 showed many variations in the C-terminal region, including the VP4-binding domain. Considering the ability of NSP4 to generate host immunity, monitoring NSP4 variations, along with those in the VP4 or VP7 protein, is important for evaluating the circulation and pathogenesis of RV. Finally, the presence of one G2P[4]E1 strain reinforces the idea that new genotype combinations emerge through reassortment and independent segregation.

Severe diarrhea outbreak in beef calves (Bos indicus) caused by G6P[11], an emergent genotype of bovine rotavirus group A / Surto de diarreia neonatal em bezerros de corte (Bos indicus) ocasionado por um genotipo emergente G6P[11] de rotavírus bovino grupo A

The episodes of diarrhea caused by neonatal bovine rotavirus group A (BoRVA) constitute one of the major health problems in the calf rearing worldwide. The main G (VP7) and P (VP4) genotypes of BoRVA strains involved in the etiology of diarrhea in calves are G6P[1], G10P[11], G6P[5], and G8P[1]. However, less frequently, other G and P genotypes have been described in BoRVA strains identified in diarrheic fecal samples of calves. This study describes the identification and molecular characterization of an emerging genotype (G6P[11]) in BoRVA strains involved in the etiology of a diarrhea outbreak in beef calves in a cattle herd of high production in extensive management system. The diarrhea outbreak, which showed high morbidity (60%) and lethality (7%) rates, occurred in calves (n= 384) Nelore (Bos indicus) up to 30-day-old from the State of Mato Grosso do Sul, Brazil. BoRVA was identified in 80% (16/20) of the fecal samples analyzed by polyacrylamide gel electrophoresis (PAGE) technique. In all PAGE-positive fecal samples were amplified products with 1,062-bp and 876-bp in the RT-PCR assays for VP7 (G type) and VP4 (VP8*) (P type) of BoRVA, respectively. The nucleotide sequence analysis of VP7 and VP4 genes of four wild-type BoRVA strains showed G6-III P[11]-III genotype/lineage. The G6P[11] genotype has been described in RVA strains of human and animal hosts, however, in calves this genotype was only identified in some cross-sectional studies and not as a single cause of diarrhea outbreaks in calves with high morbidity and lethality rates as described in this study...

Os episódios de diarreia neonatal ocasionados pelo rotavírus bovino grupo A (BoRVA) constituem-se em um dos principais problemas sanitários na criação de bezerros em todo o mundo. Os principais genotipos G (VP7) e P (VP4) de cepas de BoRVA envolvidos na etiologia da diarreia em bezerros são G6P[1], G10P[11], G6P[5] e G8P[1]. No entanto, com menor frequência, outros genotipos G e P têm sido descritos em cepas de BoRVA identificadas em amostras de fezes diarreicas de bezerros. Este estudo descreve a identificação e caracterização molecular de um genotipo emergente (G6P[11]) em cepas de BoRVA envolvidas na etiologia de um surto de diarreia em bezerros de um rebanho bovino de corte de alta produção em sistema de manejo extensivo. O surto, que apresentou altas taxas de morbidade (60%) e de letalidade (7%), ocorreu em bezerros (n=384) da raça Nelore (Bos indicus) com até 30 dias de idade, provenientes do estado do Mato Grosso do Sul, Brasil. O BoRVA foi identificado em 80% (16/20) das amostras fecais analisadas pela técnica de eletroforese em gel de poliacrilamida (PAGE). Em todas as amostras fecais PAGE-positivas foi possível a amplificação por RT-PCR de produtos com 1.062 pb e 876 pb referentes aos genes VP7 (G tipo) e VP4 (VP8*) (P tipo), respectivamente, de BoRVA. A análise da sequência de nucleotídeos dos genes VP7 e VP4 de quatro cepas de BoRVA demonstrou a presença do genotipo/linhagem G6-III P[11]-III. O genotipo G6P[11] tem sido descrito em cepas de RVA de hospedeiros humanos e animais. Contudo, em bezerros, este genotipo foi apenas identificado em alguns estudos transversais e não como a única causa de surtos de diarreia em bezerros com altas taxas de morbidade e...

The Molecular Epidemiology of Circulating Group A Rotavirus in Gwangju Metropolitan City, Korea: 2008~2012

Group A rotaviruses are a major cause of acute gastroenteritis in young children worldwide. For the proper management of rotavirus infections, knowledge of the distribution of G and P genotypes including detection of emerging genotype is crucial. Therefore, the aim of this study is to describe epidemiological changes in rotavirus gastroenteritis in Gwangju metropolitan city, South Korea. Stool samples were collected from 14,314 patients with diarrhea, who visited hospitals in Gwangju from 2008 to 2012. Samples were screened for rotavirus with Enzyme-Linked Immunosorbent Assay (ELISA) method and rotavirus P (VP4), G (VP7) genotypes were determined by reverse-transcription polymerase chain reaction. And we performed nucleotide sequencing analysis. Among a total of 14,314 samples investigated 1,982 samples (13.8%) were ELISA positive. Genotyping of Rotavirus was performed using 526 rotavirus samples. The most prevalent circulating G genotype was G1 (40.5%), followed by G2 (27.6%), G3 (19.4%), G9 (9.7%), G4 (2.5%) and G12 (0.4%). The predominant type of P genotypes was P[8] (69.6%), followed by P[4] (27.8%) and P[6] (2.3%). In this study, 13 G-P combinations were detected. From 2008 to 2010, G1P[8] was the most prevalent, followed by G3P[8]. Whereas, 2011 and 2012, G2P[4] was the most common, followed by G1P[8]. Rotavirus gastroenteritis is a common disease associated with significant morbidity, mortality and economic burden. Ongoing rotavirus surveillance to understand the distribution of G and P genotypes will be critical for the development of effective prevention measurements.

Análisis molecular del gen de la VP4 de la cepa de rotavirus bovino tipo P[5] aislada de becerros en el Estado Yaracuy / Molecular analysis of the VP4 genes of bovine rotavirus strain type P[5] isolated from calves in Yaracuy State

La diarrea neonatal bovina indiferenciada es una enfermedad multifactorial que afecta a una alta proporción de becerros (50% o más) causando hasta un 40% de mortalidad en los primeros 30 d de vida. Entre los agentes causales se incluyen muchos enteropatógenos (bacterias, virus, protozoarios), con predominio de infecciones combinadas. Entre los virus, los rotavirus constituyen los principales agentes causales de gastroenteritis aguda en diferentes especies animales. Su genoma, de 11 segmentos de ARN de doble cadena, puede rearreglarse genéticamente en coinfecciones de diferentes cepas, produciendo una progenie viral con un nuevo fenotipo. En la ganadería bovina venezolana, se han descrito los rotavirus con una prevalencia de 20-30% en animales con cuadros de diarrea entre 2-6 sem de edad. Los serotipos G6 y el genotipo P1 se han reportado con mayor frecuencia en becerros de la región central de Venezuela. Cepas de rotavirus bovino del grupo A fueron detectados por inmunoensayo enzimático (ELISA) y electroforesis en gel de poliacrilamida (PAGE), en 32 de 280 (11,43%) muestras de heces de becerros de 15 fincas del estado Yaracuy, Venezuela. La secuencia nucleotídica se logró para una de las variantes detectadas (A610). En el análisis comparativo de las secuencias de la VP8* (fragmento de la VP4) mostró corresponder al genotipo P[5]. Estos datos constituyen el primer reporte de una cepa de rotavirus bovino genotipo P[5], que circula en las fincas del estado Yaracuy, Venezuela, pudiendo servir de apoyo para la incorporación de este grupo viral en las vacunas que se utilizan en el país.

The undifferentiated neonatal bovine diarrhea is a multifactorial disease that affects a high proportion of calves (50% or more) causing up to 40% of mortality in the first 30 d of life. Among the infectious agents known to cause diarrhea in calves are the rotavirus and coronavirus. Rotaviruses are the major causative agents of acute gastroenteritis in different animal species. Their 11-segment genome of double ARN chain can genetically re-arrange different strains, producing a viral progeny with new or atypical phenotype. Rotaviruses have been described in the bovine Venezuelan cattle, with a prevalence of 20-30% in animals between 2-6 weeks of age, with episodes of diarrhea. The serotypes G6 and the genotype P1 have been reported with higher frequency in calves from the central region of Venezuela. In this investigation, rotavirus strains of cattle from Group A were detected by the enzyme-linked immunosorbent assay (ELISA) and the polyacrylamide gel electrophoresis (PAGE) in 32 of 280 (11.43%) stool samples of calves in 15 farms in the State of Yaracuy, Venezuela. The nucleotide sequence was obtained for one of the variants detected (A610) and the comparative analysis of the sequences of the VP8* (the VP4 fragment) corresponded to the P [5] genotype. These data constitute the first report of a strain of bovine rotavirus genotype P[5], which circulates in the States of Yaracuy, Venezuela, and can serve as a support for the inclusion of this viral group to the vaccines that are being used in the country.

Isolation and Characterization of G9 Human Rotaviruses

Group A rotaviruses are the most common causes of gastroenteritis among infants and young children. The outer capsid layer of the virus is composed of two structural proteins, VP4 and VP7, and they play important roles in protection by eliciting neutralization antibodies. Group A rotaviruses are subdivided into distinct G and P serotypes according to the antigenic differences of the VP7 and VP4, respectively. Rotavirus G9 serotype was thought to be the fifth most common serotype circulating among the population worldwide. In this study, G9 human rotaviruses (HRV) were isolated from fecal samples using MA104 cells and characterized. Characteristic cytopathic effects of rotavirus were observed and rotaviral antigens were confirmed by indirect immunofluorescence antibody test in MA104 cells inoculated with isolated HRV strains. The nucleotide sequences of the VP7 gene of Korean G9 HRV isolated in this study were determined and compared with those of other recent and prototype G9 rotavirus strains from other parts of the world. Also, the nucleotide sequences of VP4 and NSP4 gene of Korean G9 HRV were determined and compared with those of other rotavirus strains from other countries. The results showed that the Korean HRV isolates belong to a G9, P[8] and NSP4 B genotype. The Korean G9 HRV isolates and their nucleotide sequence data would be usefully applied for the vaccine development of HRV in the near future.

Expression and Immunoreactivity of a Human Group A Rotavirus Vp4 / 中国病毒学

Rotavirus capsid protein Vp4 plays an important role in the virus adhering and entering the cells. In this study, a Vp4 gene cloned from a rotavirus strain TB-Chen was highly expressed in E.coli BL21 (DE3). The results of the Western blot showed that the protein possesses specific immuno-reactivities and can be specifically recognized by guinea pig antibodies against rotavirus strain SA11 or Wa. Some Vp4 dimers were formed during renaturation. These data obtained from this study provide a strong basis for further study on the structure and function of the Vp4.

Virus de papiloma humano: Revisión e indicaciones terapéuticas / Human papillomavirus: Review of the different therapeutic modalities

La infección por virus de papiloma humano constituye una de las más frecuentes enfermedades de transmisión sexual. Dentro de los más de 100 tipos de virus descriptos hasta el momento, varios de los mismos son capaces de inducir transformación maligna de las células huésped. El presente trabajo consiste en una revisión de las diferentes modalidades terapéuticas utilizando una estrategia de medicina basada en evidencia.

The infection by human papillomavirus is one of the most frequent sexually transmitted diseases. Among more than 100 types of HPV described, several are capable of inducing malignant transformation in host cells. This work intend to review the different therapeutic modalities using an evidence based medicine strategy.

VP4 and VP7 Genotyping of Group A Rotavirus Isolated from Diarrhea Patients in Seoul by Multiplex PCR

The incidence and distribution of the human rotavirus G types (VP7 associated: G1~G4) and P types (VP4 associated: P[4], P[6], P[8], P[10]) were determined from 89 rotavirus strains isolated from diarrhea patients between 2001 and 2002 using reverse transcription and multiplex polymerase chain reaction. G types were identified from 83 (95.5%) and P types were from 82 (92.1%) strains. The predominant genotypes were P[4]G2 (28.1%) and P[6]G4 (27%) with much lower incidence of genotypes P[10]G1 (1.1%) and P[10]G3 (1.1%). P[9] type was not detected. A significant genotypic shift was observed that P[4] was the most prevalent genotype that accounted for 75% during the spring season of 2001, coinfection with P[4] and P[6] for 17.5%. P[6] increased gradually to account for 53% of the strains analysed in the following 2002 spring season. Mixed G types revealing coinfections G2/G3 and G3/G4 were found at low frequency (2.2%).