Four H5N2 experimental vaccine strains and the apathogenic wild duck H5N3 influenza virus A/duck/ Moscow/4182/2010 (dk/4182) were tested as a live poultry vaccine. Experimental strains had the hemagglutinin of the A/Vietnam/1203/04 strain lacking the polybasic HA cleavage site or the hemagglutinin from attenuated virus (Ku/ at) that was derived from the highly pathogenic influenza virus A/chicken/Kurgan/3/2005 (H5N1). The hemagglutinin of the Ku-at has the amino acid substitutions Asp54/Asn and Lys222/Thr in HA1 and Val48/Ile and Lys131/Thr in HA2, while maintaining the polybasic HA cleavage site at an invariable level. The other genes of these experimental strains were from the H2N2 cold-adapted master strain A/Leningrad/134/17/57 (VN-Len and Ku-Len) or from the apathogenic H6N2 virus A/gull/Moscow/3100/2006 (VN-Gull and Ku-Gull). A single immunization of mice with all tested strains elicited a high level of serum antibodies and provided complete protection against the challenge with the lethal dose of A/chicken/Kurgan/3/05. The pathogenicity indexes of the Ku-at and the other strains for chicken were virtually zero, whereas the index of the parent H5N1 virus A/chicken/Kurgan/3/2005 was 2.98. Intravenous, intranasal, and aerosol routes of vaccination were compared. It was shown that the strain dk/4182 was totally apathogenic for one-day-old chicken and provided complete protection against the highly pathogenic H5N1 virus.
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Infect Dis (Lond)
January 2025
Department of Epidemiology and Biostatistics, College of Public Health, University of Georgia, Athens, GA, USA.
Background: Whether a detected virus or bacteria is a pathogen that may require treatment, or is merely a commensal 'passenger', remains confusing for many infections. This confusion is likely to increase with the wider use of multi-pathogen PCR.
Objectives: To propose a new statistical procedure to analyse and present data from case-control studies clarifying the probability of causality.
Vet Microbiol
January 2025
College of Veterinary Medicine, Jilin Provincial Engineering Research Center of Animal Probiotics, Jilin Provincial Key Laboratory of Animal Microecology and Healthy Breeding, Engineering Research Center of Microecological Vaccines (Drugs) for Major Animal Diseases, Ministry of Education, Jilin Agricultural University, Changchun 130118, China. Electronic address:
Swine influenza virus invades the host through the respiratory mucosa, which severely restricts the development of the pig breeding industry. To construct monomeric and trimeric vaccines, we developed recombinant Escherichia coli Nissle 1917 (EcN) strains that express the receptor binding site (RBS) of the hemagglutinin (HA) antigen from H1N1 swine influenza virus. After the mucosal immunization of mice, we found that probiotics activated CD40 and CD86 in DCs and increased the levels of IL-4 and IFN-γ secretion by T cells.
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January 2025
Animal Infectious Disease Laboratory, College of Veterinary Medicine, Yangzhou University, Yangzhou, PR China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, PR China; Jiangsu Key Laboratory of Zoonoses, Yangzhou University, Yangzhou, PR China. Electronic address:
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View Article and Find Full Text PDFViruses
January 2025
School of Public Health, Bengbu Medical University, Bengbu 233030, China.
The re-emergence of the mpox pandemic poses considerable challenges to human health and societal development. There is an urgent need for effective prevention and treatment strategies against the mpox virus (MPXV). In this study, we focused on the A35R protein and created a chimeric A35R-Fc protein by fusing the Fc region of IgG to its C-terminal.
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January 2025
Département de Virologie, Institut Pasteur de Dakar, Dakar BP 220, Senegal.
Despite extensive experience with influenza surveillance in humans in Senegal, there is limited knowledge about the actual situation and genetic diversity of avian influenza viruses (AIVs) circulating in the country, hindering control measures and pandemic risk assessment. Therefore, as part of the "One Health" approach to influenza surveillance, we conducted active AIV surveillance in two live bird markets (LBMs) in Dakar to better understand the dynamics and diversity of influenza viruses in Senegal, obtain genetic profiles of circulating AIVs, and assess the risk of emergence of novel strains and their transmission to humans. Cloacal swabs from poultry and environmental samples collected weekly from the two LBMs were screened by RT-qPCR for H5, H7, and H9 AIVs.
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