Chinese Center for Disease Control and Prevention

About: Chinese Center for Disease Control and Prevention is a government organization based out in Beijing, China. It is known for research contribution in the topics: Population & Acquired immunodeficiency syndrome (AIDS). The organization has 16037 authors who have published 15098 publications receiving 423452 citations. The organization is also known as: China CDC & CCDC.

Origin, Genetic Diversity, and Evolutionary Dynamics of Novel Porcine Circovirus 3.

Abstract: Porcine circovirus 3 (PCV3) is a novel virus associated with acute PDNS (porcine dermatitis and nephropathy syndrome)-like clinical signs identified by metagenomic sequencing from swine. Its high occurrence may pose a potential threat to the swine industry worldwide. The processes resulting in the emergence and spread of PCV3 remain poorly understood. Herein, the possible origin, genotypes, and evolutionary dynamics of PCV3 based on available genomic sequences are determined. The closest ancestor of PCV3 is found to be within the clade 1 bat CVs. Using different phylogenetic methods, two major genotypes are identified, PCV3a and PCV3b. It is found that the effective population size of PCV3 increased rapidly during late 2013 to early 2014 and this is associated with the diversification of PCV3a and PCV3b. A relatively high effective reproductive number (Re) value and higher evolutionary rate were found compared to other single-stranded DNA viruses, and positive selection on codons 122 and 320 (24 of ORF2) is identified. It is hypothesized that this, together with the prediction of a potential change of an antigenic epitope at position 320, might have allowed PCV3 to escape from the host immune response. Overall, this study has important implications for understanding the ongoing PCV3 cases worldwide and will guide future efforts to develop effective preventive and control measures.

A Sabin 3-Derived Poliovirus Recombinant Contained a Sequence Homologous with Indigenous Human Enterovirus Species C in the Viral Polymerase Coding Region

Abstract: Outbreaks of poliomyelitis caused by circulating vaccine-derived polioviruses (cVDPVs) have been reported in areas where indigenous wild polioviruses (PVs) were eliminated by vaccination. Most of these cVDPVs contained unidentified sequences in the nonstructural protein coding region which were considered to be derived from human enterovirus species C (HEV-C) by recombination. In this study, we report isolation of a Sabin 3-derived PV recombinant (Cambodia-02) from an acute flaccid paralysis (AFP) case in Cambodia in 2002. We attempted to identify the putative recombination counterpart of Cambodia-02 by sequence analysis of nonpolio enterovirus isolates from AFP cases in Cambodia from 1999 to 2003. Based on the previously estimated evolution rates of PVs, the recombination event resulting in Cambodia-02 was estimated to have occurred within 6 months after the administration of oral PV vaccine (99.3% nucleotide identity in VP1 region). The 2BC and the 3Dpol coding regions of Cambodia-02 were grouped into the genetic cluster of indigenous coxsackie A virus type 17 (CAV17) (the highest [87.1%] nucleotide identity) and the cluster of indigenous CAV13-CAV18 (the highest [94.9%] nucleotide identity) by the phylogenic analysis of the HEV-C isolates in 2002, respectively. CAV13-CAV18 and CAV17 were the dominant HEV-C serotypes in 2002 but not in 2001 and in 2003. We found a putative recombination between CAV13-CAV18 and CAV17 in the 3CDpro coding region of a CAV17 isolate. These results suggested that a part of the 3Dpol coding region of PV3(Cambodia-02) was derived from a HEV-C strain genetically related to indigenous CAV13-CAV18 strains in 2002 in Cambodia.

Consumption of meat and dairy products in China: a review.

Abstract: The objective of the present paper was to review the consumption status of meat and dairy products among Chinese residents. The research topics included production, consumption and health implications of dairy and meat, and the data sources included reports of national surveys, research papers and data from the National Bureau of Statistics of China. The average intake of meat, especially pork, has continued to increase in China. Pork intake increased from 37·1 g/d in 1992 to 64·3 g/d in 2012. There was a much higher margin in rural regions; pork intake of rural residents increased from 25·0 g/d in 1992 to 59·9 g/d in 2012, which resulted in a narrowed gap between urban and rural areas. Although the average intake of dairy products increased from 14·9 g/d in 1992 to 24·7 g/d in 2012, the overall level was still lower. There was a significant difference of dairy consumption between urban and rural residents. The gap of per capita consumption of milk between urban and rural households was 3·5 kg/year in 1990, reached the maximum of 16·9 kg/year in 2003, then decreased to 8·7 kg/year in 2012. In conclusion, the finding of this review sheds light on some problems with food consumption patterns in China. Effective strategies need to be adopted in order to change the consumption patterns. The consumption of milk and replacing pork with poultry or fish or other health foods should be encouraged.

No Higher Infectivity But Immune Escape of SARS-CoV-2 501Y.V2 Variants

Abstract: The 501Y.V2 variants contain multiple mutations in the spike region. We found that they had no significant increased effect on infectivity to human cell lines and cells overexpressing human ACE2, but increased infectivity in cells overexpressing mouse ACE2 based on the pseudotyped viruses. The susceptibility of 501Y.V2 variants to many neutralizing monoclonal antibodies decreased significantly. These variants also had a significant reduced effect on the neutralization ability of convalescent and RBD protein immunized sera. The immune resistances were mainly caused by E484K and N501Y mutations located in receptor binding region. These data suggest that the enhancement of infectivity in mouse may lead to the spillover of 501Y.V2 to mouse. The immune resistance of 501Y.V2 may compromise the efficacy of monoclonal antibodies, convalescent sera and vaccines. Funding: This work was supported by General Program ofNational Natural Science Foundation of China [grant number 82073621], BILL & MELINDA GATES FOUNDATION [Investment ID INV-006379], National Science and Technology Major Projects of Drug Discovery [grant number 2018ZX09101001] and National Science and Technology Major Projects of Infectious Disease [grant number 2017ZX10304402]. Conflict of Interest: All the authors declare no competing interests. Ethical Approval: The protocol of the animal study was approved by Ethical review Committee for Animal Welfare of The National Institutes for Food and Drug Control.

The Principal Genetic Determinants for Nasopharyngeal Carcinoma in China Involve the HLA Class I Antigen Recognition Groove

Abstract: Nasopharyngeal carcinoma (NPC) is an epithelial malignancy facilitated by Epstein-Barr Virus infection. Here we resolve the major genetic influences for NPC incidence using a genome-wide association study (GWAS), independent cohort replication, and high-resolution molecular HLA class I gene typing including 4,055 study participants from the Guangxi Zhuang Autonomous Region and Guangdong province of southern China. We detect and replicate strong association signals involving SNPs, HLA alleles, and amino acid (aa) variants across the major histocompatibility complex-HLA-A, HLA -B, and HLA -C class I genes (P(HLA-A-aa-site-62) = 7.4 × 10(-29); P (HLA-B-aa-site-116) = 6.5 × 10(-19); P (HLA-C-aa-site-156) = 6.8 × 10(-8) respectively). Over 250 NPC-HLA associated variants within HLA were analyzed in concert to resolve separate and largely independent HLA-A, -B, and -C gene influences. Multivariate logistical regression analysis collapsed significant associations in adjacent genes spanning 500 kb (OR2H1, GABBR1, HLA-F, and HCG9) as proxies for peptide binding motifs carried by HLA- A*11:01. A similar analysis resolved an independent association signal driven by HLA-B*13:01, B*38:02, and B*55:02 alleles together. NPC resistance alleles carrying the strongly associated amino acid variants implicate specific class I peptide recognition motifs in HLA-A and -B peptide binding groove as conferring strong genetic influence on the development of NPC in China.