Influenza A virus prevalence and its implications on survival in mallard

2014 ◽  
Vol 60 (2-4) ◽  
pp. 55-61
Author(s):  
Mauro Giammarino ◽  
Piero Quatto ◽  
Francesca Rizzo ◽  
Maria Lucia Mandola
Keyword(s):  
Influenza A Virus ◽  
Influenza A ◽  
Sampling Method ◽  
Monitoring Program ◽  
Bird Species ◽  
Viral Disease ◽  
Inverse Sampling ◽  
Virus Prevalence ◽  
Wide Range ◽  
Wild Mallard

Avian influenza is an infectious viral disease of birds caused by type A strains of the influenza virus. Aquatic bird species have adapted to carry and transmit a wide range of influenza strains in nature. Here we report the results of a 4.5-year monitoring program forOrthomyxovirusprevalence in a population of wild mallard (Anas plathyrynchos) in northwestern Italy. To determine whetherOrthomyxovirusprevalence affects survival, we used MARK software to compare the survival of AIV-positive versus AIV-negative birds. Prevalence rates and variance were estimated using inverse sampling method. The prevalence rate of influenza A virus was 4.3% (SE 0.00116) and lifespan was shorter (29.8%) for the young infected birds than for the young non-infected birds.

Effect of pooling udder skin wipes on the detection of influenza A virus in preweaning pigs

2021 ◽  
pp. 104063872110394
Author(s):  
Anne C. de Lara ◽  
Jorge Garrido-Mantilla ◽  
Gustavo Lopez-Moreno ◽  
My Yang ◽  
David E.S.N. Barcellos ◽  
...  
Keyword(s):  
Influenza A Virus ◽  
Active Surveillance ◽  
Influenza A ◽  
Sampling Method ◽  
Threshold Value ◽  
Limited Information ◽  
Nasal Swabs ◽  
Lactating Sows ◽  
Suckling Piglets ◽  
Positive Cycle

Influenza A virus (IAV) active surveillance in pigs prior to weaning is commonly conducted by collecting individual samples, mostly nasal swabs. Recently, the use of udder skin wipes collected from lactating sows was identified as an effective sampling method to indicate IAV status of suckling piglets prior to weaning. However, there is limited information on the effect of pooling multiple udder wipes on the ability to detect IAV. We evaluated the effect of pooling 3, 5, or 10 udder wipes on the sensitivity of detecting IAV and compared the results with testing the wipes individually. The likelihood of detecting positive udder wipes decreased with pooling when the initial positive cycle threshold value was ≥31.5; pooling of up to 3 samples could be performed without affecting sensitivity significantly. Our results support pooling of udder skin wipes to conduct surveillance of IAV in pigs prior to weaning.

scholarly journals Long-term variation in influenza A virus prevalence and subtype diversity in migratory mallards in northern Europe

2014 ◽  
Vol 281 (1781) ◽  
pp. 20140098 ◽  
Author(s):  
Neus Latorre-Margalef ◽  
Conny Tolf ◽  
Vladimir Grosbois ◽  
Alexis Avril ◽  
Daniel Bengtsson ◽  
...  
Keyword(s):  
Influenza A Virus ◽  
Influenza A ◽  
Herd Immunity ◽  
Stopover Site ◽  
Virus Prevalence ◽  
Early Autumn ◽  
Temporal Occurrence ◽  
Wildlife Populations ◽  
Pronounced Peak

Data on long-term circulation of pathogens in wildlife populations are seldom collected, and hence understanding of spatial–temporal variation in prevalence and genotypes is limited. Here, we analysed a long-term surveillance series on influenza A virus (IAV) in mallards collected at an important migratory stopover site from 2002 to 2010, and characterized seasonal dynamics in virus prevalence and subtype diversity. Prevalence dynamics were influenced by year, but retained a common pattern for all years whereby prevalence was low in spring and summer, but increased in early autumn with a first peak in August, and a second more pronounced peak during October–November. A total of 74 haemagglutinin (HA)/neuraminidase (NA) combinations were isolated, including all NA and most HA (H1–H12) subtypes. The most common subtype combinations were H4N6, H1N1, H2N3, H5N2, H6N2 and H11N9, and showed a clear linkage between specific HA and NA subtypes. Furthermore, there was a temporal structuring of subtypes within seasons based on HA phylogenetic relatedness. Dissimilar HA subtypes tended to have different temporal occurrence within seasons, where the subtypes that dominated in early autumn were rare in late autumn, and vice versa. This suggests that build-up of herd immunity affected IAV dynamics in this system.

Characterization of proteins with Siaα2-3/6Gal-linked glycans from bovine milk and role of their glycans against influenza A virus

2018 ◽  
Vol 9 (10) ◽  
pp. 5198-5208 ◽  
Author(s):  
Hanjie Yu ◽  
Yaogang Zhong ◽  
Zhiwei Zhang ◽  
Xiawei Liu ◽  
Kun Zhang ◽  
...  
Keyword(s):  
Influenza A Virus ◽  
Influenza A ◽  
Bovine Milk ◽  
Milk Proteins ◽  
Biological Functions ◽  
Wide Range ◽  
Range Of Functions ◽  
Bovine Milk Proteins

The bovine milk proteins have a wide range of functions, but the role of the attached glycans in their biological functions has not been fully understood yet.

scholarly journals Low fidelity assembly of influenza A virus promotes escape from host cells

2018 ◽  
Author(s):  
Michael D. Vahey ◽  
Daniel A. Fletcher
Keyword(s):  
Influenza A Virus ◽  
Influenza A ◽  
Phenotypic Variability ◽  
Morphological Variability ◽  
Influenza Viruses ◽  
Host Cells ◽  
Temperature Changes ◽  
Wide Range ◽  
Infected Cells ◽  
Protein Components

AbstractInfluenza viruses inhabit a wide range of host environments using a limited repertoire of protein components. Unlike viruses with stereotyped shapes, influenza produces virions with significant morphological variability even within clonal populations. Whether this tendency to form pleiomorphic virions is coupled to compositional heterogeneity and whether it affects replicative fitness remains unclear. Here we address these questions by developing live strains of influenza A virus amenable to rapid compositional characterization through quantitative, site-specific labeling of viral proteins. Using these strains, we find that influenza A produces virions with broad variations in size and composition from even single infected cells. The virus leverages this phenotypic variability to survive environmental challenges including temperature changes and anti-virals. Complimenting genetic adaptations that act over larger populations and longer times, this ‘low fidelity’ assembly of influenza A virus allows small populations to survive environments that fluctuate over individual replication cycles.

scholarly journals Analysis of the Genetic Diversity Associated With the Drug Resistance and Pathogenicity of Influenza A Virus Isolated in Bangladesh From 2002 to 2019

2021 ◽  
Vol 12 ◽  
Author(s):  
Md. Golzar Hossain ◽  
Sharmin Akter ◽  
Priya Dhole ◽  
Sukumar Saha ◽  
Taheruzzaman Kazi ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Drug Resistance ◽  
Influenza A Virus ◽  
Influenza A ◽  
Neuraminidase Inhibitor ◽  
Avian Species ◽  
Lower Prevalence ◽  
Bioinformatic Tools ◽  
Wide Range ◽  
And Control

The subtype prevalence, drug resistance- and pathogenicity-associated mutations, and the distribution of the influenza A virus (IAV) isolates identified in Bangladesh from 2002 to 2019 were analyzed using bioinformatic tools. A total of 30 IAV subtypes have been identified in humans (4), avian species (29), and environment (5) in Bangladesh. The predominant subtypes in human and avian species are H1N1/H3N2 and H5N1/H9N2, respectively. However, the subtypes H5N1/H9N2 infecting humans and H3N2/H1N1 infecting avian species have also been identified. Among the avian species, the maximum number of subtypes (27) have been identified in ducks. A 3.56% of the isolates showed neuraminidase inhibitor (NAI) resistance with a prevalence of 8.50, 1.33, and 2.67% in avian species, humans, and the environment, respectively, the following mutations were detected: V116A, I117V, D198N, I223R, S247N, H275Y, and N295S. Prevalence of adamantane-resistant IAVs was 100, 50, and 30.54% in humans, the environment, and avian species, respectively, the subtypes H3N2, H1N1, H9N2, and H5N2 were highly prevalent, with the subtype H5N1 showing a comparatively lower prevalence. Important PB2 mutations such D9N, K526R, A588V, A588I, G590S, Q591R, E627K, K702R, and S714R were identified. A wide range of IAV subtypes have been identified in Bangladesh with a diversified genetic variation in the NA, M2, and PB2 proteins providing drug resistance and enhanced pathogenicity. This study provides a detailed analysis of the subtypes, and the host range of the IAV isolates and the genetic variations related to their proteins, which may aid in the prevention, treatment, and control of IAV infections in Bangladesh, and would serve as a basis for future investigations.

scholarly journals Avian Influenza A Virus Pandemic Preparedness and Vaccine Development

Vaccines ◽  
2018 ◽  
Vol 6 (3) ◽  
pp. 46 ◽  
Author(s):  
Rory de Vries ◽  
Sander Herfst ◽  
Mathilde Richard
Keyword(s):  
Avian Influenza ◽  
Influenza A Virus ◽  
Influenza A ◽  
Vaccine Development ◽  
Influenza Pandemic ◽  
Broad Host Range ◽  
Influenza A Viruses ◽  
Vaccination Strategies ◽  
Pandemic Virus ◽  
Wide Range

Influenza A viruses can infect a wide range of hosts, creating opportunities for zoonotic transmission, i.e., transmission from animals to humans, and placing the human population at constant risk of potential pandemics. In the last hundred years, four influenza A virus pandemics have had a devastating effect, especially the 1918 influenza pandemic that took the lives of at least 40 million people. There is a constant risk that currently circulating avian influenza A viruses (e.g., H5N1, H7N9) will cause a new pandemic. Vaccines are the cornerstone in preparing for and combating potential pandemics. Despite exceptional advances in the design and development of (pre-)pandemic vaccines, there are still serious challenges to overcome, mainly caused by intrinsic characteristics of influenza A viruses: Rapid evolution and a broad host range combined with maintenance in animal reservoirs, making it near impossible to predict the nature and source of the next pandemic virus. Here, recent advances in the development of vaccination strategies to prepare against a pandemic virus coming from the avian reservoir will be discussed. Furthermore, remaining challenges will be addressed, setting the agenda for future research in the development of new vaccination strategies against potentially pandemic influenza A viruses.

scholarly journals The influenza A virus NS1 protein binds small interfering RNAs and suppresses RNA silencing in plants

2004 ◽  
Vol 85 (4) ◽  
pp. 983-991 ◽  
Author(s):  
Etienne Bucher ◽  
Hans Hemmes ◽  
Peter de Haan ◽  
Rob Goldbach ◽  
Marcel Prins
Keyword(s):  
Influenza A Virus ◽  
Virus Replication ◽  
Rna Silencing ◽  
Influenza A ◽  
Rna Degradation ◽  
Plant Viruses ◽  
Sequence Specificity ◽  
Ns1 Protein ◽  
Rna Molecules ◽  
Wide Range

RNA silencing comprises a set of sequence-specific RNA degradation pathways that occur in a wide range of eukaryotes, including animals, fungi and plants. A hallmark of RNA silencing is the presence of small interfering RNA molecules (siRNAs). The siRNAs are generated by cleavage of larger double-stranded RNAs (dsRNAs) and provide the sequence specificity for degradation of cognate RNA molecules. In plants, RNA silencing plays a key role in developmental processes and in control of virus replication. It has been shown that many plant viruses encode proteins, denoted RNA silencing suppressors, that interfere with this antiviral response. Although RNA silencing has been shown to occur in vertebrates, no relationship with inhibition of virus replication has been demonstrated to date. Here we show that the NS1 protein of human influenza A virus has an RNA silencing suppression activity in plants, similar to established RNA silencing suppressor proteins of plant viruses. In addition, NS1 was shown to be capable of binding siRNAs. The data presented here fit with a potential role for NS1 in counteracting innate antiviral responses in vertebrates by sequestering siRNAs.

scholarly journals iBRAB: in silico based-designed Broad-spectrum Fab against H1N1 Influenza A Virus

2020 ◽  
Author(s):  
Phuc-Chau Do ◽  
Trung H. Nguyen ◽  
Uyen T.M. Vo ◽  
Ly Le
Keyword(s):  
Influenza A Virus ◽  
Broad Spectrum ◽  
In Silico ◽  
Influenza A ◽  
Therapeutic Vaccine ◽  
H1n1 Influenza ◽  
Therapeutic Vaccines ◽  
Fab Model ◽  
Wide Range ◽  
Different Strains

AbstractInfluenza virus A is a significant agent involved in the outbreak of worldwide epidemics, causing millions of fatalities around the world by respiratory diseases and seasonal illness. Many projects had been conducting to investigate recovered infected patients for therapeutic vaccines that have broad-spectrum activity. With the aid of the computational approach in biology, the designation for a vaccine model is more accessible. We developed an in silico protocol called iBRAB to design a broad-reactive Fab on a wide range of influenza A virus. The Fab model was constructed based on sequences and structure of available broad-spectrum Abs or Fabs against a wide range of H1N1 influenza A virus. As a result, the proposed Fab model followed iBRAB has good binding affinity over 27 selected HA of different strains of H1 influenza A virus, including wild-type and mutated ones. The examination also took by computational tools to fasten the procedure. This protocol could be applied for a fast designed therapeutic vaccine against different types of threats.

VERY LOW INFLUENZA A VIRUS PREVALENCE IN CERVIDS IN GERMAN NATIONAL PARKS

2018 ◽  
Vol 49 (1) ◽  
pp. 252-254 ◽  
Author(s):  
Sanatana-Eirini Soilemetzidou ◽  
Alex D. Greenwood ◽  
Gábor Á. Czirják
Keyword(s):  
Influenza A Virus ◽  
National Parks ◽  
Influenza A ◽  
Virus Prevalence

scholarly journals Why Are CD8 T Cell Epitopes of Human Influenza A Virus Conserved?

2019 ◽  
Vol 93 (6) ◽  
Author(s):  
Zheng-Rong Tiger Li ◽  
Veronika I. Zarnitsyna ◽  
Anice C. Lowen ◽  
Daniel Weissman ◽  
Katia Koelle ◽  
...  
Keyword(s):  
T Cell ◽  
Influenza A Virus ◽  
Influenza A ◽  
Cd8 T Cell ◽  
Influenza Vaccines ◽  
T Cell Epitopes ◽  
Class I Mhc ◽  
Mhc I ◽  
Escape Variant ◽  
Wide Range

ABSTRACTThe high degree of conservation of CD8 T cell epitopes of influenza A virus (IAV) may allow for the development of T cell-inducing vaccines that provide protection across different strains and subtypes. This conservation is not fully explained by functional constraint, since an additional mutation(s) can compensate for the replicative fitness loss of IAV escape variants. Here, we propose three additional mechanisms that contribute to the conservation of CD8 T cell epitopes of IAV. First, influenza-specific CD8 T cells may protect predominantly against severe pathology rather than infection and may have only a modest effect on transmission. Second, polymorphism of the human major histocompatibility complex class I (MHC-I) gene restricts the advantage of an escape variant to only a small fraction of the human population who carry the relevant MHC-I alleles. Finally, infection with CD8 T cell escape variants may result in a compensatory increase in the responses to other epitopes of IAV. We use a combination of population genetics and epidemiological models to examine how the interplay between these mechanisms affects the rate of invasion of IAV escape variants. We conclude that for a wide range of biologically reasonable parameters, the invasion of an escape variant virus will be slow, with a timescale of a decade or more. The results suggest T cell-inducing vaccines do not engender the rapid evolution of IAV. Finally, we identify key parameters whose measurement will allow for more accurate quantification of the long-term effectiveness and impact of universal T cell-inducing influenza vaccines.IMPORTANCEUniversal influenza vaccines against the conserved epitopes of influenza A virus have been proposed to minimize the burden of seasonal outbreaks and prepare for the pandemics. However, it is not clear how rapidly T cell-inducing vaccines will select for viruses that escape these T cell responses. Our mathematical models explore the factors that contribute to the conservation of CD8 T cell epitopes and how rapidly the virus will evolve in response to T cell-inducing vaccines. We identify the key biological parameters to be measured and questions that need to be addressed in future studies.

Sign in / Sign up

Export Citation Format

Share Document