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1.
J Med Virol ; 93(8): 5141-5145, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33527448

RESUMO

The increase of the evolutionary pressure will cause phylodynamics changes of viruses. In post-vaccine coverage era, measles viruses face more immune pressure than ever before. Vice versa, the phylodynamic changes may reflect herd immunity level provided by vaccination. In this study, we analyzed phylodynamic characteristics of measles viruses isolated from 2005 to 2017 in Jiangsu province of China using nucleoprotein gene sequences of measles viruses. The phylogenetic tree was constructed with Markov chain Monte Carlo algorithm. The mean gene distance within each group was computed with MEGA7.0 software. Our results showed that a decline trend is observed in the gene distance of nucleoprotein gene with time as well as incidence of measles from epidemic surveillance system. Two clusters of H1a genotype show cocirculation of multiple variants in early years and the disappearance of most variants with time. We explore the phylodynamic of measles virus under high immune pressure. Our findings highlight that phylodynamic of measles viruses is a helpful tool to assess the effectiveness of epidemic control.


Assuntos
Vacina contra Sarampo/imunologia , Vírus do Sarampo/genética , Sarampo/epidemiologia , Sarampo/virologia , China/epidemiologia , Genótipo , Humanos , Incidência , Sarampo/prevenção & controle , Vírus do Sarampo/classificação , Vírus do Sarampo/imunologia , Epidemiologia Molecular , Proteínas do Nucleocapsídeo/genética , Filogenia
2.
Curr Microbiol ; 77(11): 3430-3440, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32761388

RESUMO

Streptococcus parasanguinis is a primary colonizer of dental plaque and an opportunistic pathogen for subacute endocarditis. A putative fibronectin binding protein (Spaf_1409) that lacks both an N-terminal signal peptide and a C-terminal cell wall-anchoring motif was identified from the S. parasanguinis FW213 genome. Spaf_1409 was abundantly present in the cytoplasm and also was found in the cell wall preparation and culture supernatant. By using an isogenic mutant strain, MPH4, Spaf_1409 was found to mediate the binding of S. parasanguinis FW213 to fibronectin. Inactivation of Spaf_1409 did not significantly alter the mass of static biofilm, but reduced the resistance of S. parasanguinis against the shearing force in a flow cell biofilm system, resulting in scattered biofilm. The mortality in Galleria mellonella larvae infected with MPH4 was higher than in those infected with wild-type S. parasanguinis. However, fewer viable bacterial cells were recovered from larvae infected with MPH4, compared to those infected with wild-type S. parasanguinis, up to 42 h post infection, suggesting that the infection by MPH4, but not the growth, was responsible for the elevated mortality. The phagocytic analysis using flow cytometry indicated that Spaf_1409 participates in the recognition of S. parasanguinis FW213 by RAW264.7 macrophages, suggesting that inactivation of Spaf_1409 intensified the immune responses in larvae, leading to larval death. Taken together, the data indicate that Spaf_1409 plays different roles in the development of dental biofilm and in systemic infections.


Assuntos
Proteínas de Transporte , Proteínas de Fímbrias , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Fibronectinas , Proteínas de Fímbrias/metabolismo , Streptococcus/metabolismo
3.
Can J Infect Dis Med Microbiol ; 2020: 7318582, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32089759

RESUMO

Measles remains a public health concern in many regions, and the imported measles cases continue to challenge the measles elimination program for most of the countries where measles was verified to be eliminated or approaching elimination. The imported measles cases have been reported since October, 2017, in Jiangsu province, China. In this study, we reported the first imported B3 genotype measles virus from Egypt and the second imported D8 genotype measles virus from Philippines through international traveling. No secondary measles cases were found after these imported cases. Our findings highlighted the importance of measles vaccination targeting international travelers in China.

4.
BMC Infect Dis ; 18(1): 563, 2018 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-30428851

RESUMO

BACKGROUND: In recent years, outbreaks of varicella have continued to occur, and the coverage rate of varicella vaccine in Jiangsu Province, China, remains unclear. This study aims to analyse the levels of immune antibody against varicella and obtain a comprehensive understanding of the varicella attenuated live vaccine (VarV) coverage rate in children aged 1-9 years in Jiangsu Province. METHODS: From June to October 2016, a cross-sectional survey was conducted to collect 3631 serum samples from healthy children aged 1-9 years in Jiangsu Province. The immunoglobulin G (IgG) antibody levels of varicella were detected by enzyme-linked immunosorbent assay (ELISA). RESULTS: The VarV coverage rate of healthy children was only 43.1% (95% CI: 41.1-44.7%). The seroprevalence after vaccination with a single dose of VarV was only 57.1%, and the overall seropositivity and geometric antibody titre (GMC) were 43.5% and 225.4 mU/ml, respectively. The seropositivity was significantly higher in girls than in boys (χ2 = 18.82, P < 0.001). The difference in seropositivity between the 5-9 age group and 1-4 age group was statistically significant (χ2 = 84.31, P < 0.001). The difference in seropositivity between different regions was statistically significant, with the highest seropositivity in the northern area, 53.7% (χ2 = 35.64, P < 0.001). The seropositivity in the group receiving one dose of VarV was significantly higher than that of the unvaccinated group (χ2 = 205.16, P < 0.001). Linear regression analysis suggested that the GMC of varicella antibodies wanes with the time since vaccination (F = 65.01, P = 0.002). CONCLUSION: The VarV coverage rate of healthy children in Jiangsu Province was low. Sero-conversion rates were also low after one dose of VarV, and the immune effectiveness of a single dose of VarV was limited. To control the spread of varicella, VarV should be included in the routine immunization program, and strengthened immunization measures for the varicella-susceptible population warrant additional consideration.


Assuntos
Anticorpos Antivirais/sangue , Infecções Assintomáticas/epidemiologia , Varicela/sangue , Varicela/epidemiologia , Herpesvirus Humano 3/imunologia , Varicela/prevenção & controle , Vacina contra Varicela/uso terapêutico , Criança , Pré-Escolar , China/epidemiologia , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Programas de Imunização , Lactente , Masculino , Estudos Soroepidemiológicos , Vacinação/estatística & dados numéricos , Vacinas Atenuadas/uso terapêutico
5.
BMC Public Health ; 18(1): 906, 2018 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-30041607

RESUMO

BACKGROUND: To eliminate measles, the coverage of more than 90% vaccine is required in China. Nonetheless, the measles incidence still reached to 3.88 per 100,000 in 2014, which is far more than the target of 1 per 1,000,000. Moreover, there is little national surveillance to measles antibody level indicating herd immunity status in China. METHODS: We detected the level of antibody to measles using commercially available indirect enzyme-linked immunosorbent IgG assays, and calculated the protection rate of population (PRP) to measles virus infection among health peoples in China. RESULTS: During the years 2009-2015, among the Chinese population aged 0-56, PRP was 94.7, 91.6, 91.6, 84.2, 82.1, 81.0, 75.4%, respectively. Among all age bands, the PRP is lowest among children less than 12-month-age, followed by people over 15 years old. CONCLUSION: Measles antibody level among healthy population has been declined since 2012, supplemented measles vaccination activity may be necessary to eliminate measles in China.


Assuntos
Anticorpos Antivirais/sangue , Vacina contra Sarampo , Vírus do Sarampo , Sarampo/prevenção & controle , Saúde da População/estatística & dados numéricos , Vacinação , Adolescente , Adulto , Criança , Pré-Escolar , China/epidemiologia , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Imunidade Coletiva , Incidência , Lactente , Recém-Nascido , Masculino , Sarampo/sangue , Sarampo/epidemiologia , Vírus do Sarampo/imunologia , Pessoa de Meia-Idade , Vigilância da População , Testes Sorológicos , Cobertura Vacinal , Adulto Jovem
6.
Cell Mol Immunol ; 19(7): 805-819, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35551270

RESUMO

Dendritic cells (DCs) play a critical role in controlling T helper 2 (Th2) cell-dependent diseases, but the signaling mechanism that triggers this function is not fully understood. We showed that p38α activity in DCs was decreased upon HDM stimulation and dynamically regulated by both extrinsic signals and Th2-instructive cytokines. p38α-specific deletion in cDC1s but not in cDC2s or macrophages promoted Th2 responses under HDM stimulation. Further study showed that p38α in cDC1s regulated Th2-cell differentiation by modulating the MK2-c-FOS-IL-12 axis. Importantly, crosstalk between p38α-dependent DCs and Th2 cells occurred during the sensitization phase, not the effector phase, and was conserved between mice and humans. Our results identify p38α signaling as a central pathway in DCs that integrates allergic and parasitic instructive signals with Th2-instructive cytokines from the microenvironment to regulate Th2-cell differentiation and function, and this finding may offer a novel strategy for the treatment of allergic diseases and parasitic infection.


Assuntos
Hipersensibilidade , Proteína Quinase 14 Ativada por Mitógeno/metabolismo , Células Th2 , Animais , Diferenciação Celular , Citocinas/metabolismo , Células Dendríticas/metabolismo , Humanos , Hipersensibilidade/metabolismo , Inflamação/metabolismo , Camundongos , Células Th2/metabolismo
7.
Biomed J ; 45(2): 347-360, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35550340

RESUMO

BACKGROUND: Colorectal cancer (CRC) is a major health concern globally, but exhibits regional and/or environmental distinctions in terms of outcome especially for patients with stage III CRC. METHODS: From 2014 to 2016, matched pairs of tumor and adjacent normal tissue samples from 60 patients with stage I-IV CRC from Chang Gung Memorial Hospital in Taiwan were analyzed using next-generation sequencing. The DNA, mRNA, and miRNA sequences of paired tumor tissues were profiled. An observational study with survival analysis was done. Online datasets of The Cancer Genome Atlas (TCGA) and The International Cancer Genome Consortium (ICGC) were also integrated and compared. RESULTS: The gene that exhibited the highest mutation rate was adenomatous polyposis coli (APC) (75.0%), followed by TP53 (70.0%), KRAS (56.6%), and TTN (48.3%). APC was also the most frequently mutated gene in TCGA and ICGC datasets. Surprisingly, for non-metastatic cases (stages I-III), CRC patients with mutated APC had better outcome in terms of overall survival (p = 0.041) and recurrence free survival (p = 0.0048). Particularly for stage III CRC, the overall survival rate was 94.4% and 67.7%, respectively (p = 0.018), and the recurrence free survival rate was 94.4% and 16.7%, respectively (p = 0.00044). Further clinical and gene expression analyses revealed that the APC wt specimens to a greater extent exhibit poor differentiation state as well as EGFR upregulation, providing molecular basis for the poor prognosis of these patients. Finally, based on integrated transcriptome analysis, we constructed the mRNA-miRNA networks underlying disease recurrence of the stage III CRC and uncovered potential therapeutic targets for this clinical condition. CONCLUSION: For stage III CRC, patients with mutated APC had better overall and recurrence free survival.


Assuntos
Polipose Adenomatosa do Colo , Neoplasias Colorretais , Genes APC , MicroRNAs , Mutação , Polipose Adenomatosa do Colo/genética , Proteína da Polipose Adenomatosa do Colo/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Genômica , Humanos , MicroRNAs/genética , Mutação/genética , Recidiva Local de Neoplasia , RNA Mensageiro/genética
8.
Front Pharmacol ; 12: 724525, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34858170

RESUMO

Asthma is one of the most common chronic pulmonary disorders, affecting more than 330 million people worldwide. Unfortunately, there are still no specific treatments for asthma so far. Therefore, it is very important to develop effective therapeutics and medicines to deal with this intractable disease. Berberine (Ber) has fabulous anti-inflammatory and antibacterial effects, while its low water solubility and bioavailability greatly limit its curative efficiency. To improve the nasal mucosa absorption of poorly water-soluble drugs, such as Ber, we developed a platelet membrane- (PM-) coated nanoparticle (NP) system (PM@Ber-NPs) for targeted delivery of berberine to the inflammatory lungs. In vivo, PM@Ber-NPs exhibited enhanced targeting retention in the inflammatory lungs compared with free Ber. In a mouse model of house dust mite- (HDM-) induced asthma, PM@Ber-NPs markedly inhibited lung inflammation, as evident by reduced inflammatory cells and inflammatory cytokines in the lung compared with free Ber. Collectively, our study demonstrated the inhibitory actions of nasally delivered nanomedicines on HDM-induced asthma, primarily through regulating Th1/Th2 balance by enhancing IL-12 expression which could potentially reduce lung inflammation and allergic asthma.

9.
Virol J ; 7: 87, 2010 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-20444295

RESUMO

BACKGROUND: Resurgence or outbreak of measles recently occurred in both developed and developing countries despite long-standing widespread use of measles vaccine. Measles incidence in China has increased since 2002, particularly in infants and in persons >or= 15 years of age. It is speculated that infants may acquire fewer measles IgG from their mothers, resulting in the reduced duration of protection during their early months of life. This study aimed to clarify the reason of increased susceptibility to measles in young infants in China. Measles IgG in 24 measles infants

Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Imunidade Materno-Adquirida , Vacina contra Sarampo/imunologia , Sarampo/epidemiologia , Sarampo/imunologia , Adulto , China , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Lactente , Masculino , Sarampo/prevenção & controle , Mães
10.
Virol J ; 7: 105, 2010 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-20500809

RESUMO

Molecular characterization of wild-type measles viruses in China during 1995-2004 demonstrated that genotype H1 was endemic and widely distributed throughout the country. H1-associated cases and outbreaks caused a resurgence of measles beginning in 2005. A total of 210,094 measles cases and 101 deaths were reported by National Notifiable Diseases Reporting System (NNDRS) and Chinese Measles Laboratory Network (LabNet) from 2006 to 2007, and the incidences of measles were 6.8/100,000 population and 7.2/100,000 population in 2006 and 2007, respectively. Five hundred and sixty-five wild-type measles viruses were isolated from 24 of 31 provinces in mainland China during 2006 and 2007, and all of the wild type virus isolates belonged to cluster 1 of genotype H1. These results indicated that H1-cluster 1 viruses were the predominant viruses circulating in China from 2006 to 2007. This study contributes to previous efforts to generate critical baseline data about circulating wild-type measles viruses in China that will allow molecular epidemiologic studies to help measure the progress made toward China's goal of measles elimination by 2012.


Assuntos
Vírus do Sarampo/genética , Sarampo/virologia , China/epidemiologia , Genótipo , Sarampo/epidemiologia , Vírus do Sarampo/classificação , Vírus do Sarampo/isolamento & purificação , Dados de Sequência Molecular , Filogenia
11.
Sci Rep ; 10(1): 4526, 2020 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-32161294

RESUMO

Colorectal cancer (CRC) is one of the most commonly diagnosed cancers worldwide. While both genetic and environmental factors have been linked to the incidence and mortality associated with CRC, an ethnic aspect of its etiology has also emerged. Since previous large-scale cancer genomics studies are mostly based on samples of European ancestry, the patterns of clinical events and associated mechanisms in other minority ethnic patients suffering from CRC are largely unexplored. We collected 104 paired and adjacent normal tissue and CRC tumor samples from Taiwanese patients and employed an integrated approach - paired expression profiles of mRNAs and microRNAs (miRNAs) combined with transcriptome-wide network analyses - to catalog the molecular signatures of this regional cohort. On the basis of this dataset, which is the largest ever reported for this type of systems analysis, we made the following key discoveries: (1) In comparison to the The Cancer Genome Atlas (TCGA) data, the Taiwanese CRC tumors show similar perturbations in expressed genes but a distinct enrichment in metastasis-associated pathways. (2) Recurrent as well as novel CRC-associated gene fusions were identified based on the sequencing data. (3) Cancer subtype classification using existing tools reveals a comparable distribution of tumor subtypes between Taiwanese cohort and TCGA datasets; however, this similarity in molecular attributes did not translate into the predicted subtype-related clinical outcomes (i.e., death event). (4) To further elucidate the molecular basis of CRC prognosis, we developed a new stratification strategy based on miRNA-mRNA-associated subtyping (MMAS) and consequently showed that repressed WNT signaling activity is associated with poor prognosis in Taiwanese CRC. In summary, our findings of distinct, hitherto unreported biosignatures underscore the heterogeneity of CRC tumorigenesis, support our hypothesis of an ethnic basis of disease, and provide prospects for translational medicine.


Assuntos
Transformação Celular Neoplásica/genética , Neoplasias Colorretais/etiologia , Perfilação da Expressão Gênica , Transcriptoma , Biomarcadores Tumorais , Neoplasias Colorretais/epidemiologia , Biologia Computacional/métodos , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , MicroRNAs/genética , Gradação de Tumores , Metástase Neoplásica , Estadiamento de Neoplasias , Prognóstico , Interferência de RNA , RNA Mensageiro/genética , Taiwan/epidemiologia
12.
Virol J ; 6: 135, 2009 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-19737391

RESUMO

Measles morbidity and mortality decreased significantly after measles vaccine was introduced into China in 1965. From 1995 to 2004, average annual measles incidence decreased to 5.6 cases per 100,000 population following the establishment of a national two-dose regimen. Molecular characterization of wild-type measles viruses demonstrated that genotype H1 was endemic and widely distributed throughout the country in China during 1995-2004. A total of 124,865 cases and 55 deaths were reported from the National Notifiable Diseases Reporting System (NNDRS) in 2005, which represented a 69.05% increase compared with 2004. Over 16,000 serum samples obtained from 914 measles outbreaks and the measles IgM positive rate was 81%. 213 wild-type measles viruses were isolated from 18 of 31 provinces in China during 2005, and all of the isolates belonged to genotype H1. The ranges of the nucleotide sequence and predicted amino acid sequence homologies of the 213 genotype H1 strains were 93.4%-100% and 90.0%-100%, respectively. H1-associated cases and outbreaks caused the measles resurgence in China in 2005. H1 genotype has the most inner variation within genotype, it could be divided into 2 clusters, and cluster 1 viruses were predominant in China throughout 2005.


Assuntos
Vírus do Sarampo/classificação , Vírus do Sarampo/isolamento & purificação , Sarampo/epidemiologia , Sarampo/virologia , Anticorpos Antivirais/sangue , China/epidemiologia , Análise por Conglomerados , Doenças Endêmicas , Genótipo , Humanos , Imunoglobulina M/sangue , Incidência , Vírus do Sarampo/genética , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico
13.
Braz J Infect Dis ; 23(1): 66-69, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30876879

RESUMO

Here we reported the outbreak of measles cases caused by the genotype D8 measles virus for the first time in Jiangsu province in China, which was possibly imported by a foreign student from Laos. Throat swab specimens were collected, and used to isolate virus. 634-bp fragment of the N gene and 1854-bp fragment of H gene were amplified by reverse transcription-PCR and sequenced, respectively. Phylogenetic results indicated that they belonged to genotype D8 measles virus. Further epidemiology investigation showed that the adults with D8 measles virus infection did not receive measles vaccine before having measles. In China, almost all D8 genotype MeV only infected those population without receiving measles vaccine immunization. Therefore, it is still necessary to implement the supplement activity of measles immunization target adult with immunity gap.


Assuntos
Doenças Transmissíveis Importadas/epidemiologia , Doenças Transmissíveis Importadas/virologia , Surtos de Doenças , Vírus do Sarampo/genética , Sarampo/epidemiologia , Sarampo/virologia , Adulto , China/epidemiologia , Feminino , Genótipo , Humanos , Vírus do Sarampo/isolamento & purificação , Filogenia
14.
Expert Rev Vaccines ; 17(5): 445-452, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29478347

RESUMO

BACKGROUND: In China, one dose measles-mumps-rubella vaccine (MMR) was administered to children aged 18-24 months. The mumps incidence was still high. Data on the waning immunity to mumps after MMR vaccination are limited. This study aimed to describe the waning immunity to mumps in kindergarten and primary school children to provide a scientific basis for confirming an optimal age for a second dose. METHODS: An observational, prospective study on one-dose MMR in children in kindergarten and primary school was conducted from 2015 to 2016. Waning immunity to mumps in terms of seropositivity and geometric antibody concentration (GMC) with time was analyzed. RESULTS: In total, 7436 eligible subjects in kindergarten (3435) and primary school (4001) were included in 2015. The overall GMC (201.7 U/ml) and seropositivity (75.4%) to mumps antibodies in 2016 were significantly lower compared to those in 2015 (218.7 U/ml, 78.4%). Asymptomatic infection occurred within one year in 8.8% of children who received one-dose MMR. CONCLUSIONS: Children who received one-dose MMR in kindergarten and primary school were at high risk of mumps infection, and waning immunity occurred with time. Determining the optimal age for the second dose of MMR in children should be prioritized to prevent mumps epidemics.


Assuntos
Anticorpos Antivirais/sangue , Esquemas de Imunização , Vacina contra Sarampo-Caxumba-Rubéola/administração & dosagem , Caxumba/prevenção & controle , Criança , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Masculino , Vacina contra Sarampo-Caxumba-Rubéola/imunologia , Caxumba/epidemiologia , Caxumba/imunologia , Estudos Prospectivos , Fatores de Tempo
15.
Sci Rep ; 5: 14660, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26423223

RESUMO

The mumps surveillance data from 2004 to 2011 showed that the incidence of mumps remained high after the one-dose measles-mumps-rubella (MMR) vaccine was introduced in China in 2008. A cross-sectional survey of mumps IgG in the general population of Jiangsu province was conducted in 2012 to gain comprehensive information on the immunity profile of the general population. The mean incidence was 15.2 per 100 000 individuals in Jiangsu province from 2004-2013. Two mumps incidence peaks were observed each year after introduction of the one-dose MMR vaccine. The seroprevalence did not significantly differ by region or sex, while the GMC significantly differed by region and sex. The overall GMC in Jiangsu province was 99.1 IU/ml (95% CI: 90.1-108.2), while the seroprevalence was only 59.1% (95% CI: 56.5-61.6). The seroprevalences for the 2 age groups that received the one-dose MMR vaccine, with reported coverage exceeding 95%, were 42.6% and 70.0%, respectively. The data on the incidence, MMR coverage, and seroprevalence in children younger than 6 years of age indicate that a two-dose MMR strategy should be considered. Mumps surveillance should be strengthened in children aged 6-11 and in those aged 12-17 because of their high contact rates and relatively low seroprevalences.


Assuntos
Vacina contra Sarampo-Caxumba-Rubéola/imunologia , Caxumba/prevenção & controle , Vacinação , Adolescente , Adulto , Anticorpos Antivirais/sangue , Criança , Pré-Escolar , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Caxumba/epidemiologia , Caxumba/imunologia , Vírus da Caxumba/imunologia , Estudos Soroepidemiológicos , Potência de Vacina , Adulto Jovem
16.
Sci Rep ; 5: 7999, 2015 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-25613734

RESUMO

Rubella remains a significant burden in mainland China. In this report, 667 viruses collected in 24 of 31 provinces of mainland China during 2010-2012 were sequenced and analyzed, significantly extending previous reports on limited numbers of viruses collected before 2010. Only viruses of genotypes 1E and 2B were found. Genotype 1E viruses were found in all 24 provinces. Genotype 1E viruses were likely introduced into mainland China around 1997 and endemic transmission of primarily one lineage became established. Viruses reported here from 2010-2012 are largely in a single cluster within this lineage. Genotype 2B viruses were rarely detected in China prior to 2010. This report documents a previously undetected 2B lineage, which likely became endemic in eastern provinces of China between 2010 and 2012. Bayesian analyses were performed to estimate the evolutionary rates and dates of appearance of the genotype 1E and 2B viral linages in China. A skyline plot of viral population diversity did not provide evidence of reduction of diversity as a result of vaccination, but should be useful as a baseline for such reductions as vaccination programs for rubella become widespread in mainland China.


Assuntos
Evolução Molecular , Genótipo , Vírus da Rubéola/genética , Rubéola (Sarampo Alemão)/epidemiologia , Rubéola (Sarampo Alemão)/virologia , China/epidemiologia , Variação Genética , Geografia , Humanos , Incidência , Filogenia , RNA Viral/genética , Vírus da Rubéola/classificação , Vírus da Rubéola/isolamento & purificação , Análise de Sequência de DNA , Proteínas do Envelope Viral/genética
17.
Braz. j. infect. dis ; 23(1): 66-69, Jan.-Feb. 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1039220

RESUMO

ABSTRACT Here we reported the outbreak of measles cases caused by the genotype D8 measles virus for the first time in Jiangsu province in China, which was possibly imported by a foreign student from Laos. Throat swab specimens were collected, and used to isolate virus. 634-bp fragment of the N gene and 1854-bp fragment of H gene were amplified by reverse transcription-PCR and sequenced, respectively. Phylogenetic results indicated that they belonged to genotype D8 measles virus. Further epidemiology investigation showed that the adults with D8 measles virus infection did not receive measles vaccine before having measles. In China, almost all D8 genotype MeV only infected those population without receiving measles vaccine immunization. Therefore, it is still necessary to implement the supplement activity of measles immunization target adult with immunity gap.


Assuntos
Humanos , Feminino , Adulto , Surtos de Doenças , Doenças Transmissíveis Importadas/epidemiologia , Doenças Transmissíveis Importadas/virologia , Sarampo/epidemiologia , Sarampo/virologia , Vírus do Sarampo/genética , Filogenia , China/epidemiologia , Genótipo , Vírus do Sarampo/isolamento & purificação
18.
PLoS One ; 8(6): e66771, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23825562

RESUMO

BACKGROUND: Changes in the epidemiological characteristics of measles since 2007 appeared in the Jiangsu province. Although the reported coverage with two doses of measles vaccine was greater than 95% in most regions of the province, measles incidence remained high across the whole province. Cross-sectional serological surveys of measles antibodies in the Jiangsu province of China were conducted from 2008 to 2010 to assess and track population immunity. METHODS: Measles-specific IgG levels were measured in serum samples using ELISA. GMTs and seroprevalence with 95% CIs were calculated by region, gender, and age. ANOVA and χ(2) tests were used to test for statistically significant differences between groups for GMT levels and seroprevalence, respectively. RESULTS: Seroprevalence showed a significantly increasing trend annually (CMH χ(2) = 40.32, p<0.0001). Although the seroprevalence among children aged 2-15 years was consistently over 95%, vaccine-induced measles antibodies may wane over time. Measles seropositivity in the Jiangsu province was 91.7% (95% CI: 90.1-93.2%) in 2010. Among adults aged 15 to 29-year-olds, the seropositivity rate was 88.4% (95% CI: 82.7-92.8%). CONCLUSIONS: Vaccination strategies may need to be adjusted depending on the individual age and regions, particularly individuals between the ages of 8 months-14 years old and 20-29 years old. Additional SIAs are likely required to eliminate measles in China.


Assuntos
Anticorpos Antivirais/sangue , Vacina contra Sarampo/imunologia , Vírus do Sarampo/imunologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Anticorpos Antivirais/imunologia , Criança , Pré-Escolar , China/epidemiologia , Estudos Transversais , Coleta de Dados , Feminino , Geografia , Humanos , Lactente , Masculino , Vírus do Sarampo/fisiologia , Pessoa de Meia-Idade , Distribuição por Sexo , Carga Viral , Adulto Jovem
19.
PLoS One ; 8(9): e73374, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24073194

RESUMO

BACKGROUND: China experienced several large measles outbreaks in the past two decades, and a series of enhanced control measures were implemented to achieve the goal of measles elimination. Molecular epidemiologic surveillance of wild-type measles viruses (MeV) provides valuable information about the viral transmission patterns. Since 1993, virologic surveillnace has confirmed that a single endemic genotype H1 viruses have been predominantly circulating in China. A component of molecular surveillance is to monitor the genetic characteristics of the hemagglutinin (H) gene of MeV, the major target for virus neutralizing antibodies. PRINCIPAL FINDINGS: Analysis of the sequences of the complete H gene from 56 representative wild-type MeV strains circulating in China during 1993-2009 showed that the H gene sequences were clustered into 2 groups, cluster 1 and cluster 2. Cluster1 strains were the most frequently detected cluster and had a widespread distribution in China after 2000. The predicted amino acid sequences of the H protein were relatively conserved at most of the functionally significant amino acid positions. However, most of the genotype H1 cluster1 viruses had an amino acid substitution (Ser240Asn), which removed a predicted N-linked glycosylation site. In addition, the substitution of Pro397Leu in the hemagglutinin noose epitope (HNE) was identified in 23 of 56 strains. The evolutionary rate of the H gene of the genotype H1 viruses was estimated to be approximately 0.76×10(-3) substitutions per site per year, and the ratio of dN to dS (dN/dS) was <1 indicating the absence of selective pressure. CONCLUSIONS: Although H genes of the genotype H1 strains were conserved and not subjected to selective pressure, several amino acid substitutions were observed in functionally important positions. Therefore the antigenic and genetic properties of H genes of wild-type MeVs should be monitored as part of routine molecular surveillance for measles in China.


Assuntos
Variação Genética/genética , Hemaglutininas Virais/genética , Vírus do Sarampo/genética , Sarampo/genética , China , Evolução Molecular , Genótipo , Humanos , Sarampo/transmissão , Sarampo/virologia , Vírus do Sarampo/isolamento & purificação , Vírus do Sarampo/patogenicidade , Dados de Sequência Molecular , Fatores de Tempo
20.
PLoS One ; 7(4): e34401, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22532829

RESUMO

The incidence of measles in China from 1991 to 2008 was reviewed, and the nucleotide sequences from 1507 measles viruses (MeV) isolated during 1993 to 2008 were phylogenetically analyzed. The results showed that measles epidemics peaked approximately every 3 to 5 years with the range of measles cases detected between 56,850 and 140,048 per year. The Chinese MeV strains represented three genotypes; 1501 H1, 1 H2 and 5 A. Genotype H1 was the predominant genotype throughout China continuously circulating for at least 16 years. Genotype H1 sequences could be divided into two distinct clusters, H1a and H1b. A 4.2% average nucleotide divergence was found between the H1a and H1b clusters, and the nucleotide sequence and predicted amino acid homologies of H1a viruses were 92.3%-100% and 84.7%-100%, H1b were 97.1%-100% and 95.3%-100%, respectively. Viruses from both clusters were distributed throughout China with no apparent geographic restriction and multiple co-circulating lineages were present in many provinces. Cluster H1a and H1b viruses were co-circulating during 1993 to 2005, while no H1b viruses were detected after 2005 and the transmission of that cluster has presumably been interrupted. Analysis of the nucleotide and predicted amino acid changes in the N proteins of H1a and H1b viruses showed no evidence of selective pressure. This study investigated the genotype and cluster distribution of MeV in China over a 16-year period to establish a genetic baseline before MeV elimination in Western Pacific Region (WPR). Continuous and extensive MeV surveillance and the ability to quickly identify imported cases of measles will become more critical as measles elimination goals are achieved in China in the near future. This is the first report that a single endemic genotype of measles virus has been found to be continuously circulating in one country for at least 16 years.


Assuntos
Genes Virais/genética , Vírus do Sarampo/genética , Sarampo/transmissão , China/epidemiologia , Genótipo , Humanos , Incidência , Sarampo/epidemiologia , Sarampo/virologia , Vírus do Sarampo/isolamento & purificação , Vigilância da População
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