Avian-like H1N1 and reassortant H3N2 and H1N2 influenza A viruses with a human-like haemagglutinin have been co-circulating in swine in Europe for more than a decade. We aimed to examine the infection dynamics of the three swine influenza virus (SIV) lineages at the farm level, and to identify possible regional and seasonal variations in their circulation. Sera were collected from six successive generations of fattening pigs (2006-2008) in a total 80 farrow-to-finish herds in Belgium, Italy, France and Spain and examined for antibodies against the three SIVs in haemagglutination inhibition tests. Overall, in all regions and periods, 9.7% of all farms were negative for SIV, 49% were infected with one subtype, 38% with two subtypes and 3.9% with all three SIVs. We found serological evidence for the circulation of all three subtypes in Belgium, Italy and Spain, while only infections with H1N1 and H1N2 SIVs were detected in France. Despite temporary changes in the circulation of H1N2 in Belgium and in Spain, there was no true seasonal variation. The exact combination of subtypes on the same farm differed in each of the sampling periods. On the other hand, 21 farms were found to be consistently infected with the same SIV subtype throughout the study. This can either be explained by the persistence of the virus in a farm, or by the periodical re-introduction of SIVs of the same subtype.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.vetmic.2012.11.014 | DOI Listing |
J Nanobiotechnology
January 2025
College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China.
Background: The rapid mutation of avian influenza virus (AIV) poses a significant threat to both the poultry industry and public health. Herein, we have successfully developed an mRNA-LNPs candidate vaccine for H5 subtype highly pathogenic avian influenza and evaluated its immunogenicity and protective efficacy.
Results: In experiments on BALB/c mice, the vaccine candidate elicited strong humoral and a certain cellular immune responses and protected mice from the heterologous AIV challenge.
J Pharm Biomed Anal
January 2025
School of Pharmacy, Shandong University of Traditional Chinese Medicine, Jinan 250355, China; State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China. Electronic address:
Trametes robiniophila Murr. (Huaier) is a traditional medicinal fungus known for its pharmacological properties, including heat-clearing, detoxifying, anti-inflammatory, and antitumor effects. Our previous research has demonstrated its antiviral activity, but the exact therapeutic mechanisms remain unclear.
View Article and Find Full Text PDFAm J Respir Cell Mol Biol
January 2025
The University of Texas Medical Branch at Galveston, Microbiology and Immuology, Galveston, Texas, United States.
Exposure to influenza A virus (IAV), respiratory syncytial virus (RSV), and human metapneumovirus (hMPV) is well-known to increase the risk of pneumonia in humans. Type I interferon (IFN-I) is a hallmark response to acute viral infections, and alveolar macrophages (AMs) constitute the first line of airway defense against opportunistic bacteria. Our study reveals that virus-induced IFN-I receptor (IFNAR1) signaling directly impairs AM-dependent antibacterial protection.
View Article and Find Full Text PDFSci Adv
January 2025
Department of Microbiology and Immunology, Cornell University College of Veterinary Medicine, Ithaca, NY 14853, USA.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and influenza viruses lead to severe respiratory illnesses and death in humans, exacerbated in individuals with underlying health conditions, remaining substantial global public health concerns. Here, we developed a bivalent replication-incompetent single-cycle pseudotyped vesicular stomatitis virus vaccine that incorporates both a prefusion-stabilized SARS-CoV-2 spike protein lacking a furin cleavage site and a full-length influenza A virus neuraminidase protein. Vaccination of K18-hACE2 or C57BL/6J mouse models generated durable levels of neutralizing antibodies, T cell responses, and protection from morbidity and mortality upon challenge with either virus.
View Article and Find Full Text PDFNucleic Acids Res
January 2025
CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.
The heterotrimeric RNA-dependent RNA polymerase (RdRp) of influenza A virus catalyzes viral RNA transcription (vRNA→mRNA) and replication (vRNA→cRNA→vRNA) by adopting different conformations. A switch from transcription to replication occurs at a relatively late stage of infection. We recently reported that the viral NS2 protein, expressed at later stages from a spliced transcript of the NS segment messenger RNA (mRNA), inhibits transcription, promotes replication and plays a key role in the transcription-to-replication switch.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!