The polymerase acidic (PA) I38T substitution is a dominant marker of resistance to baloxavir. We evaluated the impact of I38T on the fitness of a contemporary influenza A(H3N2) virus. Influenza A/Switzerland/9715293/2013 (H3N2) wild-type (WT) virus and its I38T mutant were rescued by reverse genetics. Replication kinetics were compared using ST6GalI-MDCK and A549 cells and infectivity/contact transmissibility were evaluated in guinea pigs. Nasal wash (NW) viral titres were determined by TCID50 ml in ST6GalI-MDCK cells. Competition experiments were performed and the evolution of viral population was assessed by droplet digital RT-PCR. I38T did not alter replication. I38T induced comparable titres vs the WT in guinea pigs NWs and the two viruses transmitted equally by direct contact. However, a 50 %:50 % mixture inoculum evolved to mean WT/I38T ratios of 71 %:29 % and 66.4 %:33.6 % on days 4 and 6 p.i., respectively. Contemporary influenza A(H3N2)-I38T PA variants may conserve a significant level of viral fitness.
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Tuberculosis (Edinb)
January 2025
Clinical Research Center, Masan National Tuberculosis Hospital, Changwon, 51755, Republic of Korea. Electronic address:
Tuberculosis (TB) remains a highly lethal infectious disease. The primary preventive measure is Bacille Calmette-Guérin (BCG), a live attenuated vaccine. However, the current intradermal vaccination method with 10-dose vials faces challenges such as inadequate infant injection, inaccurate dispensing, and unstable storage.
View Article and Find Full Text PDFJ Immunol Methods
January 2025
ICAR-Indian Veterinary Research Institute, Bangalore, Karnataka 560024, India.
Bluetongue (BT) is a vector-borne viral disease of multiple domestic and wild ruminants across the globe. The VP7 protein of bluetongue virus (BTV) is the major immune-dominant structural protein that is conserved across the BTV serotypes and therefore, targeted for the development of immuno-diagnostics for BT. In this study, full-length recombinant VP7 protein (rVP7) of BTV-1 was expressed in Trochoplusia ni derived insect cells (Tn5) using codon-optimized synthetic gene construct through baculovirus expression system.
View Article and Find Full Text PDFPLoS One
January 2025
Department of Pathology, University of Texas Medical Branch, Galveston, Texas, United States of America.
Tick-borne spotted fever rickettsioses (SFRs) continue to cause severe illness and death in otherwise-healthy individuals due to lack of a timely and reliable diagnostic laboratory test. We recently identified a diagnostic biomarker for SFRs, the putative N-acetylmuramoyl-l-alanine amidase RC0497. Here, we developed a prototype laboratory test that targets RC0497 for diagnosis of SFRs.
View Article and Find Full Text PDFParasit Vectors
January 2025
Veterinary and Animal Science School, Federal University of Goiás, Goiânia, Goiás, 74690-900, Brazil.
Background: Brazilian spotted fever is a tick-borne disease caused by the bacterium Rickettsia rickettsii, whose main vector in Brazil is the tick Amblyomma sculptum. Amplifying hosts are essential for the perpetuation of this bacterium in the tick population as they can be sources of infection during bacteremic periods. Recent studies demonstrated the ability of suids (Sus scrofa) to sustain populations of A.
View Article and Find Full Text PDFVet Res Forum
December 2024
Department of Theriogenology, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran.
The cooling procedure markedly diminishes the quality of guinea pig () sperms, primarily because their membranes are highly susceptible to this process. This susceptibility triggers the generation of reactive oxygen species and free radicals, ultimately leading to lipid peroxidation in the sperm membrane. Surprisingly, there has been a lack of research on the use of Tris-based extenders to safeguard guinea pig sperm under refrigeration conditions.
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