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2.
China CDC Wkly ; 3(15): 316-319, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-34594874

RESUMO

What is already known about this topic?: Significant changes in human immunodeficiency virus (HIV) transmission modes have occurred in China, and the proportion of heterosexual transmission increased in recent years. What is added by this report?: The proportions of diverse transmission routes and subgroups of heterosexual transmission were analyzed by provincial-level administrative divisions (PLADs), and nationwide spatial clustering of HIV transmission through commercial heterosexual contact (CHC) and non-marital non-commercial heterosexual contact (NMNCHC) was explored. What are the implications for public health practice?: This report provides evidence for geographic clustering of HIV transmission through CHC and NMNCHC in China and identifies priority regions where specified research and targeted HIV prevention and control strategies should be implemented.

5.
China CDC Wkly ; 3(30): 637-644, 2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34594958

RESUMO

What is already known about this topic? Though coronavirus disease 2019 (COVID-19) has largely been controlled in China, several outbreaks of COVID-19 have occurred from importation of cases or of suspected virus-contaminated products. Though several outbreaks have been traced to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) isolated on the outer packaging of cold chain products, live virus has not been obtained. What is added by this report? In September 2020, two dock workers were detected as having asymptomatic SARS-CoV-2 infection using throat swabs during routine screening in Qingdao, China. Epidemiological information showed that the two dock workers were infected after contact with contaminated outer packaging, which was confirmed by genomic sequencing. Compared to the Wuhan reference strain, the sequences from the dock workers and the package materials differed by 12-14 nucleotides. Furthermore, infectious virus from the cold chain products was isolated by cell culture, and typical SARS-CoV-2 particles were observed under electron microscopy. What are the implications for public health practice? The international community should pay close attention to SARS-CoV-2 transmission mode through cold chain, build international cooperative efforts in response, share relevant data, and call on all countries to take effective prevention and control measures to prevent virus contamination in cold-chain food production, marine fishing and processing, transportation, and other operations.

7.
China CDC Wkly ; 3(36): 751-756, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34594983

RESUMO

What is known about this topic?: The emerging H5Ny lineages of the avian influenza virus (AIV) with genomic reassortments have posed a continuous threat to animals and human beings. Since the first case of avian influenza A (H5N6) virus infection in 2014, the World Health Organization has reported a total of 38 cases by August 6, 2021. What is added by this report?: A total of 5 new cases of H5N6 that occurred from May 2021 to July 2021 in Sichuan Province, China were reported in this study. Epidemiological and laboratory information of the five cases were investigated. The genomic analysis of the H5N6 genomes showed the features of AIV genomic reassortments and key residue substitutions. What are the implications for public health practice?: The emergence of human cases infected by AIV H5Ny lineages through time demonstrates a risk of the persistence and evolution of the virus to trigger sporadic outbreaks and even pandemics, which need continuous surveillance.

8.
China CDC Wkly ; 3(39): 831-834, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34595002
9.
China CDC Wkly ; 3(8): 157-158, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-34595032
12.
Clin Infect Dis ; 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34609506

RESUMO

BACKGROUND: The longitudinal antigen-specific immunity in COVID-19 convalescents is crucial for long-term protection upon individual re-exposure to SARS-CoV-2, and even more pivotal for ultimately achieving population-level immunity. To better understand the features of immune memory in individuals with different disease severities at one year post-disease onset we conducted this cohort study. METHODS: We conducted a systematic antigen-specific immune evaluation in 101 COVID-19 convalescents, who had asymptomatic, mild, moderate, or severe disease, through two visits at months 6 and 12 post-disease onset. The SARS-CoV-2-specific antibodies, comprising NAb, IgG, and IgM, were assessed by mutually corroborated assays, i.e. neutralization, enzyme-linked immunosorbent assay (ELISA), and microparticle chemiluminescence immunoassay (MCLIA). Meanwhile, the T-cell memory against SARS-CoV-2 spike, membrane and nucleocapsid proteins was tested through enzyme-linked immunospot assay (ELISpot), intracellular cytokine staining (ICS), and tetramer staining-based flow cytometry, respectively. RESULTS: SARS-CoV-2-specific IgG antibodies, and also NAb can persist among over 95% COVID-19 convalescents from 6 months to 12 months after disease onset. At least 19/71 (26%) of COVID-19 convalescents (double positive in ELISA and MCLIA) had detectable circulating IgM antibody against SARS-CoV-2 at 12m post-disease onset. Notably, the percentages of convalescents with positive SARS-CoV-2-specific T-cell responses (at least one of the SARS-CoV-2 antigen S1, S2, M and N protein) were 71/76 (93%) and 67/73 (92%) at 6m and 12m, respectively. Furthermore, both antibody and T-cell memory levels of the convalescents were positively associated with their disease severity. CONCLUSIONS: SARS-CoV-2-specific cellular and humoral immunities are durable at least until one year after disease onset.

13.
J Virol ; : JVI0146421, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34586860

RESUMO

Bats are reservoirs of important zoonotic viruses like Nipah and SARS viruses. However, whether the blood-sucking arthropods on the body surface of bats also carry these viruses, and the relationship between viruses carried by the blood-sucking arthropods and viruses carried by bats, have not been reported. This study collected 686 blood-sucking arthropods on the body surface of bats from Yunnan Province, China between 2012 and 2015, and they included wingless bat flies, bat flies, ticks, mites, and fleas. The viruses carried by these arthropods were analyzed using meta-transcriptomic approach, and 144 highly diverse positive-sense single-stranded RNA, negative-sense single-stranded RNA, and double-stranded RNA viruses were found, of which 138 were potentially new viruses. These viruses were classified into 14 different virus families or orders, including Bunyavirales, Mononegavirales, Reoviridae, and Picornavirales. Further analyses found that Bunyavirales were the most abundant virus group (84% of total virus RNA) in ticks, whereas narnaviruses were the most abundant (52-92%) in the bat flies and wingless bat flies libraries, followed by solemoviruses (1-29%) and reoviruses (0-43%). These viruses were highly structured based on the arthropod types. It is worth noting that no bat-borne zoonotic viruses were found in the virome of bat-infesting arthropod, seemly not supporting that bat surface arthropods are vectors of zoonotic viruses carried by bats. IMPORTANCE Bats are reservoir of many important viral pathogens. To evaluate whether bat-parasitic blood-sucking arthropods participate in the circulation of these important viruses, it is necessary to conduct unbiased virome studies on these arthropods. We evaluated five types of blood-sucking parasitic arthropods on the surface of bats in Yunnan, China and identified a variety of viruses, some of which had high prevalence and abundance level, although there is limited overlap in virome between distant arthropods. While most of the virome discovered here are potentially arthropod-specific viruses, we identified three possible arboviruses, including one orthobunyavirus and two vesiculoviruses (family Rhabdoviridae), suggesting bat-parasitic arthropods carry viruses with risk of spillage, which warrants further study.

15.
Lancet Reg Health West Pac ; 16: 100268, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34568854

RESUMO

Background: Non pharmaceutical interventions (NPI) including hand washing directives were implemented in China and worldwide to combat the COVID-19 pandemic, which are likely to have had impacted a broad spectrum of enteric pathogen infections. Methods: Etiologically diagnostic data from 45 937 and 67 395 patients with acute diarrhea between 2012 and 2020, who were tested for seven viral pathogens and 13 bacteria respectively, were analyzed to assess the changes of enteric pathogen infections in China during the first COVID-19 pandemic year compared to pre-pandemic years. Findings: Test positive rates of all enteric viruses decreased during 2020, compared to the average levels during 2012-2019, with a relative decrease of 71•75% for adenovirus, 58•76% for norovirus, 53•50% for rotavirus A, and 72•07% for the combination of other four uncommon viruses. In general, a larger reduction of positive rate in viruses was seen among adults than pediatric patients. A rebound of rotavirus A was seen after September 2020 in North China rather than South China. Test positive rates of bacteria decreased during 2020, compared to the average levels during 2012-2019, excepting for nontyphoidal Salmonella and Campylobacter coli with 66•53% and 90•48% increase respectively. This increase was larger for pediatric patients than for adult patients. Interpretation: The activity of enteric pathogens changed profoundly alongside the NPIs implemented during the COVID-19 pandemic in China. Greater reductions of the test positive rates were found for almost all enteric viruses than for bacteria among acute diarrhea patients, with further large differences by age and geography. Lifting of NPIs will lead to resurgence of enteric pathogen infections, particularly in children whose immunity may not have been developed and/or waned. Funding: China Mega-Project on Infectious Disease Prevention; National Natural Science Funds.

16.
Cell Rep ; 36(12): 109734, 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34551288

RESUMO

Glucocorticoid-induced tumor necrosis factor receptor family-related protein (GITR) is a critical regulatory molecule in modulation of T cell immune responses. Here we report the mouse GITR (mGITR) and mGITR ligand (mGITRL) complex structure and find that the binding interface of mGITR and mGITRL is distinct from the typical tumor necrosis factor superfamily (TNFSF)/TNF receptor superfamily (TNFRSF) members. mGITR binds to its ligand with a single domain, whereas the binding interface on mGITRL is located on the side, which is distal from conserved binding sites of TNFSF molecules. Mutational analysis reveals that the binding interface of GITR/GITRL in humans is conserved with that in the mouse. Substitution of key interacting D93-I94-V95 (DIV) in mGITR with the corresponding K93-F94-S95 (KFS) in human GITR enables cross-recognition with human GITRL and cross-activation of receptor signaling. The findings of this study substantially expand our understanding of the interaction of TNFSF/TNFRSF superfamily molecules and can benefit the future design of biologics by targeting GITR/GITRL.

17.
Int Immunol ; 33(10): 529-540, 2021 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-34491327

RESUMO

Coronavirus disease 2019 (COVID-19) has caused millions of deaths, and serious consequences to public health, economies and societies. Rapid responses in vaccine development have taken place since the isolation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the release of the viral genome sequence. By 21 May 2021, 101 vaccines were under clinical trials, and published data were available for 18 of them. Clinical study results from some vaccines indicated good immunogenicity and acceptable reactogenicity. Here, we focus on these 18 vaccines that had published clinical data to dissect the induced humoral and cellular immune responses as well as their safety profiles and protection efficacy.


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/imunologia , Imunidade Celular/imunologia , Imunidade Humoral/imunologia , Animais , Humanos , Imunogenicidade da Vacina/imunologia , SARS-CoV-2/imunologia
18.
J Immunol ; 207(8): 2167-2178, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34535575

RESUMO

Marsupials are one of three major mammalian lineages that include the placental eutherians and the egg-laying monotremes. The marsupial brushtail possum is an important protected species in the Australian forest ecosystem. Molecules encoded by the MHC genes are essential mediators of adaptive immune responses in virus-host interactions. Yet, nothing is known about the peptide presentation features of any marsupial MHC class I (MHC I). This study identified a series of possum MHC I Trvu-UB*01:01 binding peptides derived from wobbly possum disease virus (WPDV), a lethal virus of both captive and feral possum populations, and unveiled the structure of marsupial peptide/MHC I complex. Notably, we found the two brushtail possum-specific insertions, the 3-aa Ile52Glu53Arg54 and 1-aa Arg154 insertions are located in the Trvu-UB*01:01 peptide binding groove (PBG). The 3-aa insertion plays a pivotal role in maintaining the stability of the N terminus of Trvu-UB*01:01 PBG. This aspect of marsupial PBG is unexpectedly similar to the bat MHC I Ptal-N*01:01 and is shared with lower vertebrates from elasmobranch to monotreme, indicating an evolution hotspot that may have emerged from the pathogen-host interactions. Residue Arg154 insertion, located in the α2 helix, is available for TCR recognition, and it has a particular influence on promoting the anchoring of peptide WPDV-12. These findings add significantly to our understanding of adaptive immunity in marsupials and its evolution in vertebrates. Our findings have the potential to impact the conservation of the protected species brushtail possum and other marsupial species.

19.
Emerg Microbes Infect ; 10(1): 1819-1823, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34392820

RESUMO

In mid-November 2020, deaths of whooper swan were reported in the Yellow River Reservoir Area, China. In the present study, we describe the genetic characterizations and phylogenetic relationships of four clade 2.3.4.4b H5N8 highly avian influenza viruses (HPAIVs) identified from a sick whooper swan and environmental samples collected in the Yellow River Reservoir Area in late November 2020. They were closely related to recent H5Nx HPAIVs causing outbreaks in Eurasia in the 2020-2021 influenza season, suggesting these isolates might be imported into China via migratory birds. The newly identified H5N8 HPAIVs possessed Q226 and G228 (H3 numbering), indicating that they prefer to avian-like receptors. However, they had three mutations falling within known antigenic regions, including T144A in antigenic region A, T192I in antigenic region B, and N240D in antigenic region D. Our study highlights the risk of the rapid global spread of H5N8 HPAIVs and the necessity for continuous monitoring of avian influenza viruses in wild birds.

20.
Nat Commun ; 12(1): 5026, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-34408158

RESUMO

Nationwide prospective surveillance of all-age patients with acute respiratory infections was conducted in China between 2009‒2019. Here we report the etiological and epidemiological features of the 231,107 eligible patients enrolled in this analysis. Children <5 years old and school-age children have the highest viral positivity rate (46.9%) and bacterial positivity rate (30.9%). Influenza virus, respiratory syncytial virus and human rhinovirus are the three leading viral pathogens with proportions of 28.5%, 16.8% and 16.7%, and Streptococcus pneumoniae, Mycoplasma pneumoniae and Klebsiella pneumoniae are the three leading bacterial pathogens (29.9%, 18.6% and 15.8%). Negative interactions between viruses and positive interactions between viral and bacterial pathogens are common. A Join-Point analysis reveals the age-specific positivity rate and how this varied for individual pathogens. These data indicate that differential priorities for diagnosis, prevention and control should be highlighted in terms of acute respiratory tract infection patients' demography, geographic locations and season of illness in China.


Assuntos
Bactérias/isolamento & purificação , Infecções Bacterianas/microbiologia , Infecções Respiratórias/microbiologia , Infecções Respiratórias/virologia , Viroses/virologia , Vírus/isolamento & purificação , Adolescente , Adulto , Bactérias/classificação , Bactérias/genética , Infecções Bacterianas/epidemiologia , Criança , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Lactente , Masculino , Estudos Prospectivos , Infecções Respiratórias/epidemiologia , Estações do Ano , Viroses/epidemiologia , Vírus/classificação , Vírus/genética , Adulto Jovem
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