ETIDIOH - NEW

  Abstract Background :  Chikungunya virus (CHIKV) has historically been regarded as a low-fatality infection ; however, growing evidence from diverse study designs demonstrated a substantial mortality burden during large-scale epidemics. In 2025, Réunion Island experienced a major CHIKV outbreak , raising renewed concerns about its fatal impact.  Methods :  We conducted an ecological time-series analysis of all-cause mortality during the 2025 chikungunya epidemic. Expected deaths were estimated using two complementary approaches: (i) a baseline based on age-specific mean mortality rates from the same calendar months in the post-pandemic period and (ii) long-term Poisson regression models using a log-link function and population offset, excluding the COVID-19 pandemic period. Excess mortality was calculated as the difference between observed and expected deaths during periods when observed mortality significantly exceeded the upper bound of the 95% confidence interva...

  Abstract Influenza A viruses continually pose pandemic threats, underscoring the need for timely development of Candidate Vaccine Viruses (CVVs) that meet regulatory expectations for vaccine manufacturing. This protocol describes the procedures used at CDC to generate recombinant CVVs through reverse genetics in accordance with World Health Organization guidelines and CDC’s internal Quality System Requirements (QSR)1,2,3. The QSR incorporates relevant principles from the FDA’s Good Manufacturing Practice (GMP) and Good Laboratory Practice (GLP) regulations, providing a structured framework that ensures documentation integrity, material traceability, and quality oversight during all stages of CVV development. The protocol provides detailed steps for plasmid preparation , virus rescue in Vero cells , and amplification in embryonated chicken eggs , and outlines characterization assays used to confirm the suitability and safety attributes of each CVV. This standardized, quality-drive...

  Abstract Influenza A virus (IAV) is a zoonotic pathogen with a broad host range, posing an ongoing threat to global public health . As the core subunit of the IAV polymerase , polymerase basic protein 1 (PB1) is essential for viral replication and transcription , and its mutations are key drivers of viral evolution . This review evaluates the impact of PB1 mutations on IAV evolution, with a focus on polymerase activity, host adaptation, transmissibility, and virulence. Additionally, it discusses the implications of these mutations for vaccine development. The review aims to provide insights that can inform influenza surveillance, identify novel antiviral targets, and guide vaccine design. Source:  Link:  https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2026.1768665/full ____

  Abstract In the present study, we assessed the pathogenicity of H5N8 avian influenza viruses belongs to the clade 2.3.4.4b in chicken. Birds of three different dose groups, 10 2 , 10 4 , and 10 6 EID 50 were used in the study. No mortality was observed in 10 2 EID0 group. Percent cumulative mortality of 10 4 and 10 6 EID 50 group was 66.67 and 100 %, respectively. Varying duration of MDT of 3.2 and 2 days was observed in 10 4 and 10 6 EID 50 group, respectively. The CID 50 of virus was found to be 10 4.5 EID 50 . High no. of viral RNA copies were found both in oropharyngeal and cloacal swabs and in various organs of birds infected in 10 4 and 10 6 EID 50 group. Significant gross and histological changes and presence of viral antigen in various organs were observed in 10 4 and 10 6 EID 50 group. So, the study concludes that Indian HPAI, H5N8 isolates are highly pathogenic in nature to chicken by affecting most organs systemically. CID 50 of this H5N8 virus indicates poor adaption ...