ABSTRACT
From 2017 to 2020, 1 078 piglet diarrhea samples were collected from 6 pig farms in different districts of Shanghai. Multiple RT-PCR method was used for detection and analysis to study the infection status of bovine viral diarrhea virus (BVDV) in swinery in Shanghai. The results showed that the overall detection rate of BVDV in swinery in Shanghai was 7.14% (77/1 078), and showed an increasing trend year by year. The mixed infection rate of BVDV and other diarrhea pathogens was high, with the highest dual infection rate (65%, 26/40), mainly BVDV/PASTV (61.54%, 16/26). On this basis, the triple infection rate was 25% (10/40), mainly BVDV/PAStV/PKoV (40%, 4/10) infection mode;The quadruple infection rate was 10% (4/40), which was dominated by BVDV/PAStV/PEDV/PSV (50%, 2/4) infection. The BVDV prevalence in swinery was seasonal, and the prevalence in spring (10.36%) and autumn (13.59%) was higher than that in summer (6.8%) and winter (2.66%). The positive rate of BVDV in different pig farms was significantly different by 0-24.07%. In view of the detection rate of diarrhea virus dominated by PEDV in pig farm 2 had been high in recent years, this study further monitored the infection of BVDV in this pig farm, and found that the detection rate of BVDV in this pig farm was increasing year by year from 2017 to 2019, with the highest detection rate in 2019 (8.61%, 42/488);The mixed infection of BVDV and other diarrhea pathogens was also serious, with the dual infection rate of 57.58% (19/32), triple infection rate of 21.21% (7/32), quadruple infection rate of 21.21% (7/32), respectively. This study enriched the epidemic data of BVDV in swinery in Shanghai, and could provide reference for the prevention and control of pig epidemics.
ABSTRACT
Objective: The aim of this study was to analyze the prevalence of vaginal flora and drug resistance in bacterial vaginitis among girls. Methods: A total of 3099 girls (0-10 years old) with vaginitis who visited the Beijing Children's Hospital from January 2020 to December 2021 were included in the present study. The clinical data, results of bacterial culture of vaginal secretions, and drug sensitivity reports of the subjects were collected and analyzed. Results: Of the 3099 girls with vaginitis, 399 girls had a positive bacterial culture of vaginal secretions. Nineteen types of bacteria were cultured from the vaginal secretions of these 399 girls, with a total of 419 strains. The top three infective bacteria were Haemophilus influenzae (127 strains, 30.31%), Staphylococcus aureus (66 strains, 15.75%), and Streptococcus agalactiae (32 strains, 7.64%). Additionally, 20 girls were simultaneously infected with two types of bacteria. Staphylococcus aureus, Group G Streptococcus, Haemophilus parainfluenzae, and Pseudomonas aeruginosa more frequently occurred in mixed infections. The number and bacterial detection rate among school-age girls were higher than those of preschool-age girls. We found seasonal variation in infection rates, and vaginitis among girls was higher in summer. Recurrence of vaginitis in girls was not related to the type of pathogenic bacteria in the infection. Drug sensitivity analyses showed that the resistance rates of clindamycin and erythromycin were generally high, 70-100%. After the coronavirus disease 2019 outbreak, the resistance rates of some antibiotics had decreased to varying degrees. Conclusion: Improving the understanding of vaginal flora and drug resistance in girls with vaginitis will facilitate the selection of highly effective and sensitive antibacterial drugs and reduce the production of drug-resistant strains.
ABSTRACT
Interferons (IFNs) including type I/III IFNs are the major components of the host innate immune response against porcine epidemic diarrhea virus (PEDV) infection, and several viral proteins have been identified to antagonize type I/III IFNs productions through diverse strategies. However, the modulation of PEDV infection upon the activation of the host's innate immune response has not been fully characterized. In this study, we observed that various IFN-stimulated genes (ISGs) were upregulated significantly in a time- and dose-dependent manner in LLC-PK1 cells infected with the PEDV G2 strain FJzz1. The transcriptions of IRF9 and STAT1 were increased markedly in the late stage of FJzz1 infection and the promotion of the phosphorylation and nuclear translocation of STAT1, implicating the activation of the JAK-STAT signaling pathway during FJzz1 infection. In addition, abundant type I/III IFNs were produced after FJzz1 infection. However, type I/III IFNs and ISGs decreased greatly in FJzz1-infected LLC-PK1 cells following the silencing of the RIG-I-like receptors (RLRs), including RIG-I and MDA5, and the Toll-like receptors (TLRs) adaptors, MyD88 and TRIF. Altogether, FJzz1 infection induces the production of type-I/III IFNs in LLC-PK1 cells, in which RLRs and TLRs signaling pathways are involved, followed by the activation of the JAK-STAT signaling cascade, triggering the production of numerous ISGs to exert antiviral effects of innate immunity.
Subject(s)
Interferon Type I , Porcine epidemic diarrhea virus , Animals , Cell Line , Signal Transduction , Swine , Toll-Like ReceptorsABSTRACT
The close relations between dogs (Canis lupus familiaris) and humans lay a foundation for cross species transmissions of viruses. The co-existence of multiplex viruses in the host accelerate viral variations. For effective prediction and prevention of potential epidemic or even pandemic, the metagenomics method was used to investigate the gut virome status of 45 domestic healthy dogs which have extensive contact with human beings. A total of 248.6 GB data (505, 203, 006 valid reads, 150 bp in length) were generated and 325, 339 contigs, which were best matched with viral genes, were assembled from 46, 832, 838 reads. In the aggregate, 9,834 contigs (3.02%) were confirmed for viruses. The top 30 contigs with the most reads abundance were mapped to DNA virus families Circoviridae, Parvoviridae and Herpesviridae; and RNA virus families Astroviridae, Coronaviridae and Picornaviridae, respectively. Numerous sequences were assigned to animal virus families of Astroviridae, Coronaviridae, Circoviridae, etc.; and phage families of Microviridae, Siphoviridae, Ackermannviridae, Podoviridae, Myoviridae and the unclassified phages. Further, several sequences were homologous with the insect and plant viruses, which reflects the diet and habitation of dogs. Significantly, canine coronavirus was uniquely identified in all the samples with high abundance, and the phylogenetic analysis therefore showed close relationship with the human coronavirus strain 229E and NL63, indicating the potential risk of canine coronavirus to infect humans by obtaining the ability of cross-species transmission. This study emphasizes the high detection frequency of virus harbored in the enteric tract of healthy contacted animal, and expands the knowledge of the viral diversity and the spectrum for further disease-association studies, which is meaningful for elucidating the epidemiological and biological role of companion animals in public health.
ABSTRACT
To understand the infection of Porcine Deltacoronavirus (PDCoV) in herds with diarrhea, a pair of RT-PCR detection primers were designed based on the conserved sequence of PDCoV M gene The detection limit of RT-PCR is 3.92 10 sup 3 /sup copies / muL, and the specificity and sensitivity are both good. This method was used to detect 518 swine diarrhea stool samples from 2015 to 2017 in pig farms around Shanghai, and 25 PDCoV positive samples were detected. Among the positive samples detected, the mixed infection rate of PDCoV with porcine kobuvirus (PKV) and porcine astrovirus (PAstV) was higher, at 40% and 48%, respectively;PDCoV and swine epidemic The mixed infection rate of porcine epidemic diarrhea virus (PEDV) was 8.0%, and no mixed samples of PDCoV and porcine transmissible gastroenteritis virus (TEGV) were detected. Randomly select 10 PDCoV positive samples and analyze the homology of the amplified M gene fragments. As a result, the nucleotide homology in the 10 samples reached 95.0%-99.6%, and the homology with the PDCoV strain registered in GenBank It is 96.1%-100%, indicating that the genetic differences of the current PDCoV strains are not large. This study provides a reference for understanding the prevalence of PDCoV.
ABSTRACT
Infectious bovine viral diarrhea virus (BVDV) cDNA clones have been used for the expression of classical swine fever virus (CSFV) genes for immune prevention and control. However, can it be used for the expression of an allogenetic fragment? To answer this question, a BVDV chimeric virus expressing the spike (S) antigen fragment of porcine epidemic diarrhea virus (PEDV) was constructed. Antigen S499-602 was inserted into pig-derived BVDV-2 infectious cDNA clone pASH28 in tandem by overlapping PCR, located between the seventh and eighth amino acids at the N-terminus of the capsid (C) protein of BVDV. Indirect immunofluorescence assay confirmed that the chimeric virus vASH-dS312 containing double S499-602 sequences was successfully assembled, which could react with the monoclonal antibody (MAb) against BVDV E2 and PEDV S proteins. Further western blot analysis confirmed that the exogenous S499-602 double protein could be stably expressed. Next, the chimeric virus vASH-dS312 was administered to BALB/C mice either orally or by intramuscular injection. The immunized mice were healthy and showed no signs of toxicity. IgG against BVDV and PEDV antibodies could be detected in the mice administered vASH-dS312 by intramuscular injection, which had neutralization activity against BVDV and PEDV. Thus, this study reported a new insertion site in the BVDV infectious cDNA clone that could successfully express an allogenetic antigen.