Protective efficacy of vaccines of the Korea national antigen bank against the homologous H5Nx clade 2.3.2.1 and clade 2.3.4.4 highly pathogenic avian influenza viruses.

Protective efficacy of vaccines of the Korea national antigen bank against the homologous H5Nx clade 2.3.2.1 and clade 2.3.4.4 highly pathogenic avian influenza viruses. Vaccine. 2019 Oct 25;: Authors: Kang YM, Cho HK, Kim HM, Lee MH, To TL, Kang HM Abstract The occurrence of severe outbreaks of highly pathogenic avian influenza in Korea led to establishment of a national antigen bank for emergency preparedness. Here, we developed five vaccines for this bank (clade 2.3.2.1C, clade 2.3.4.4A, B, C, and D) by reverse genetics, inactivated them with formalin, and evaluated the protective efficacy and potency of serial dilutions against lethal homologous challenge in specific-pathogen-free chickens. After vaccination with one dose, each vaccine resulted in 100% survival, with no clinical symptoms, or lack of detectable virus shedding, and high levels of pre-challenge protective immunity (8.4-10.2 log2). After vaccination with one-tenth of the full dose, protection was similar to that with the full dose. After vaccination with one-hundredth of the initial dose, survival was 20-80%, and all vaccines showed virus shedding. Four vaccines (excluding clade 2.3.2.1C) had satisfactory potency. In antibody-persistence tests, all vaccines maintained long-lasting protective immunity. Our results suggest that inactivated reverse-genetics vaccines genetically matched to outbreak viruses provide adequate protection after a single vaccination. PMID: 31669062 [PubMed - ...
Source: Vaccine - Category: Allergy & Immunology Authors: Tags: Vaccine Source Type: research

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Abstract In China, influenza A(H7N9) virus appeared in 2013, then mutated into a highly pathogenic virus, causing outbreaks among poultry and cases in humans. Since September 2017, extensive use of the corresponding vaccine, H7-Re1, successfully reduced virus prevalence. However, in 2019, a novel antigenic variant emerged, posing considerable economic and public health threats.A. PMID: 31855533 [PubMed - as supplied by publisher]
Source: Emerging Infectious Diseases - Category: Infectious Diseases Authors: Tags: Emerg Infect Dis Source Type: research
My sister-in-law, Vicki Gregory, who has died of cancer aged 51, was an international expert in influenza surveillance and research.As a stalwart of theWorldwide Influenza Centre at theFrancis Crick Institute in London, Vicki was held in high regard by colleagues around the globe. With her wealth of knowledge and experience, notably during bird flu outbreaks, she collaborated with many of the laboratories of theWorld Health Organization (WHO)’s influenza response system.Continue reading...
Source: Guardian Unlimited Science - Category: Science Authors: Tags: Medical research Flu Science Society Vaccines and immunisation Punk Source Type: news
Armando Isibasi Constantino López-Macías The clinical effects and immunological response to the influenza vaccine in women who later become pregnant remain to be thoroughly studied. Here, we report the medical outcomes of 40 women volunteers who became pregnant after vaccination with an experimental virus-like particle (VLP) vaccine against pandemic influenza A(H1N1)2009 (influenza A(H1N1)pdm09) and their infants. When included in the VLP vaccine trial, none of the women were pregnant and were randomly assigned to one of the following groups: (1) placebo, (2) 15 μg dose of VLP vaccine, or (3) ...
Source: Viruses - Category: Virology Authors: Tags: Article Source Type: research
In March 2013, the first human case of zoonotic H7N9 avian influenza virus (AIV) infection was reported in China. This virus has been circulating in domestic poultry in China while mutating to highly pathogenic AIV (HPAIV) since 2017, which caused human infections and poultry outbreaks. In 2019, a novel reassortant H7N2 HPAIV, A/chicken/China/SJZ1/2019(SJZ1), was isolated from H7 –Re2-vaccinated layers. We analyzed the genetic, pathogenic, and antigenic characteristics of SJZ1. Analysis of the entire SJZ1 genomic sequence revealed that it comprised at least two different sources; the PB2, PB1, PA, HA (H7), M, and NS ...
Source: Journal of Infection - Category: Infectious Diseases Authors: Tags: Letter to the Editor Source Type: research
In this study, we aimed to generate Newcastle disease virus (NDV) vectored H7 serotype-specific vaccines by expressing the consensus sequence of the HA protein. Conventional NDV strain LaSota vector and a chimeric NDV vector containing the avian paramyxovirus type-2 F and HN protein were able to express the consensus sequence of HA protein. The protective efficacy of vaccines was evaluated in broiler chickens and in turkeys. One-day-old poults were prime immunized with the chimeric vector expressing the HA protein followed by boost immunization with LaSota vector expressing the HA protein or co-expressing the HA and NA pro...
Source: Vaccine - Category: Allergy & Immunology Authors: Tags: Vaccine Source Type: research
This article summarizes Canada's pandemic public health measures strategy, as described in the recently updated CPIP Public Health Measures Annex. The strategy builds on lessons learned during the 2009 H1N1 pandemic. Key elements of the public health measures strategy include individual measures (e.g. hand hygiene, self-isolation when ill), community-based measures (e.g. school closures, cancellation of mass gatherings), management of cases and close contacts, travel and border-related actions and public education. Factors that influence the effectiveness of public health measures in a pandemic include the pandemic epidemi...
Source: Can Commun Dis Rep - Category: Infectious Diseases Authors: Tags: Can Commun Dis Rep Source Type: research
In this study we aimed to verify clinical ND suspicions in poultry holdings in Egypt suffering from respiratory distress and elevated mortality, comparing two groups of ND-vaccinated poultry holdings in three governorates. Besides testing for Newcastle disease virus (NDV), samples were screened for infectious bronchits virus (IBV) and avian influenza virus (AIV) by RT-qPCR as well as by non-directed cell-culture approach on LMH-cells. Virulent NDV was confirmed only in group A (n = 16) comprising small-scale holdings. Phylogenetic analysis of the fusion protein gene of 11 NDV-positive samples obtained from th...
Source: Avian Pathology - Category: Pathology Authors: Tags: Avian Pathol Source Type: research
Conclusions: Human challenge studies and systems biology approaches are important tools that should be used in concert to advance our understanding of influenza infection and provide targets for novel therapeutics and immunizations. Introduction Although influenza virus was recognized as an important pathogen over a century ago, influenza continues to cause a significant burden of disease. In the United States alone, it's estimated that in the 2017–2018 season there were 959,000 hospitalizations related to influenza illness, and 79,400 deaths (CDC, 2018). Worldwide, WHO estimates that annual influenza...
Source: Frontiers in cellular and infection microbiology - Category: Microbiology Source Type: research
We describe the unexpected binding of S-layer to cells devoid of DC-SIGN but also confirm that the presence of DC-SIGN was essential for S-layer’s antiviral activity. S-layer protein exerted its antiviral effect with different kinetics than mannan, a known viral inhibitor that also acts on DC-SIGN (Yu et al., 2017). Together our results suggest that inhibition of viral entry by S-layer occurs via a novel S-layer/DC-SIGN interaction. Materials and Methods Isolation of S-Layer Proteins S-layer proteins were extracted from overnight cultures of L. acidophilus ATCC 4356 cells grown in MRS medium at 37°C by using 6...
Source: Frontiers in Microbiology - Category: Microbiology Source Type: research
Although influenza science has come a long way since the 1918 Spanish flu pandemic, influenza continues to be a leading cause of morbidity and mortality. This review provides current, evidence-based recommendations regarding influenza prevention, diagnosis, and treatment. Nurse practitioners can help reduce influenza-associated morbidity and mortality by receiving annual influenza vaccinations, encouraging patients and community members to receive annual influenza vaccinations, developing and implementing strategies to improve influenza vaccination rates, encouraging preventive personal and community nonpharmaceutical inte...
Source: The Journal for Nurse Practitioners - Category: Nursing Authors: Tags: Featured Article Source Type: research
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