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Virology Journal Oct 2021The fifth wave of H7N9 avian influenza virus caused a large number of human infections and a large number of poultry deaths in China. Since September 2017, mainland...
BACKGROUND
The fifth wave of H7N9 avian influenza virus caused a large number of human infections and a large number of poultry deaths in China. Since September 2017, mainland China has begun to vaccinate poultry with H5 + H7 avian influenza vaccine. We investigated the avian influenza virus infections in different types of live poultry markets and samples before and after genotype H5 + H7 vaccination in Nanchang, and analyzed the changes of the HA subtypes of AIVs.
METHODS
From 2016 to 2019, we monitored different live poultry markets and collected specimens, using real-time reverse transcription polymerase chain reaction (RT-PCR) technology to detect the nucleic acid of type A avian influenza virus in the samples. The H5, H7 and H9 subtypes of influenza viruses were further classified for the positive results. The χ test was used to compare the differences in the separation rates of different avian influenza subtypes.
RESULTS
We analyzed 5,196 samples collected before and after vaccination and found that the infection rate of AIV in wholesale market (21.73%) was lower than that in retail market (24.74%) (P < 0.05). Among all the samples, the positive rate of sewage samples (33.90%) was the highest (P < 0.001). After vaccination, the positive rate of H5 and H7 subtypes decreased, and the positive rate of H9 subtype and untypable HA type increased significantly (P < 0.001). The positive rates of H9 subtype in different types of LPMs and different types of samples increased significantly (P < 0.01), and the positive rates of untypable HA type increased significantly in all environmental samples (P < 0.05).
CONCLUSIONS
Since vaccination, the positive rates of H5 and H7 subtypes have decreased, but the positive rates of H9 subtypes have increased to varying degrees in different testing locations and all samples. This results show that the government should establish more complete measures to achieve long-term control of the avian influenza virus.
Topics: Animals; China; Humans; Influenza A Virus, H7N9 Subtype; Influenza in Birds; Influenza, Human; Poultry; Sewage; Vaccination
PubMed: 34715890
DOI: 10.1186/s12985-021-01683-0 -
Revue Scientifique Et Technique... Apr 2009
Topics: Animals; Birds; Disease Outbreaks; Humans; Influenza A Virus, H5N1 Subtype; Influenza in Birds; Influenza, Human
PubMed: 19618615
DOI: 10.20506/rst.28.1.1873 -
Revue Scientifique Et Technique... Apr 2009
Topics: Animals; Birds; Disease Outbreaks; Humans; Influenza A Virus, H5N1 Subtype; Influenza in Birds; Influenza, Human; Zoonoses
PubMed: 19618614
DOI: 10.20506/rst.28.1.1874 -
Cytogenetic and Genome Research 2007During the last decade the number of reported outbreaks caused by highly pathogenic avian influenza (HPAI) in domestic poultry has drastically increased. At the same... (Review)
Review
During the last decade the number of reported outbreaks caused by highly pathogenic avian influenza (HPAI) in domestic poultry has drastically increased. At the same time, low pathogenic avian influenza (LPAI) strains, such as H9N2 in many parts of the Middle East and Asia and H6N2 in live bird markets in California, have become endemic. Each AI outbreak brings the concomitant possibility of poultry-to-human transmission. Indeed, human illness and death have resulted from such occasional transmissions with highly pathogenic avian H7N7 and H5N1 viruses while avian H9N2 viruses have been isolated from individuals with mild influenza. The transmission of avian influenza directly from poultry to humans has brought a sense of urgency in terms of understanding the mechanisms that lead to interspecies transmission of influenza. Domestic poultry species have been previously overlooked as potential intermediate hosts in the generation of influenza viruses with the capacity to infect humans. In this review, we will discuss molecular and epidemiological aspects that have led to the recurrent emergence of avian influenza strains with pandemic potential, with a particular emphasis on the current Asian H5N1 viruses.
Topics: Animals; Birds; Disease Outbreaks; Humans; Immunity, Innate; Influenza A Virus, H5N1 Subtype; Influenza Vaccines; Influenza in Birds; Influenza, Human
PubMed: 17675883
DOI: 10.1159/000103203 -
Science in China. Series C, Life... May 2009
Topics: Animals; Birds; China; Humans; Influenza A Virus, H5N1 Subtype; Influenza in Birds; Influenza, Human
PubMed: 19471861
DOI: 10.1007/s11427-009-0058-8 -
Revue Scientifique Et Technique... Aug 2000Highly pathogenic (HP) avian influenza (AI) (HPAI) is an extremely contagious, multi-organ systemic disease of poultry leading to high mortality, and caused by some H5... (Review)
Review
Highly pathogenic (HP) avian influenza (AI) (HPAI) is an extremely contagious, multi-organ systemic disease of poultry leading to high mortality, and caused by some H5 and H7 subtypes of type A influenza virus, family Orthomyxoviridae. However, most AI virus strains are mildly pathogenic (MP) and produce either subclinical infections or respiratory and/or reproductive diseases in a variety of domestic and wild bird species. Highly pathogenic avian influenza is a List A disease of the Office International des Epizooties, while MPAI is neither a List A nor List B disease. Eighteen outbreaks of HPAI have been documented since the identification of AI virus as the cause of fowl plague in 1955. Mildly pathogenic avian influenza viruses are maintained in wild aquatic bird reservoirs, occasionally crossing over to domestic poultry and causing outbreaks of mild disease. Highly pathogenic avian influenza viruses do not have a recognised wild bird reservoir, but can occasionally be isolated from wild birds during outbreaks in domestic poultry. Highly pathogenic avian influenza viruses have been documented to arise from MPAI viruses through mutations in the haemagglutinin surface protein. Prevention of exposure to the virus and eradication are the accepted methods for dealing with HPAI. Control programmes, which imply allowing a low incidence of infection, are not an acceptable method for managing HPAI, but have been used during some outbreaks of MPAI. The components of a strategy to deal with MPAI or HPAI include surveillance and diagnosis, biosecurity, education, quarantine and depopulation. Vaccination has been used in some control and eradication programmes for AI.
Topics: Animals; Birds; Disease Outbreaks; Humans; Influenza A virus; Influenza in Birds; Mammals
PubMed: 10935274
DOI: 10.20506/rst.19.2.1230 -
Frontiers in Cellular and Infection... 2017We analyzed five H5N1 avian influenza viruses (AIVs) isolated from different birds in 2012 in China. Based on whole-genome sequences, we divided the viruses into four...
We analyzed five H5N1 avian influenza viruses (AIVs) isolated from different birds in 2012 in China. Based on whole-genome sequences, we divided the viruses into four genotypes. The DKE26, GSE43, and DKE53 viruses belonged to Genotypes 1-3, respectively. The CKE93 and CKE96 viruses were classified into Genotype 4. Genotypes 1-3 correspond to the viruses containing the HA gene of clade 2.3.2, and Genotype 4 is the virus that bears the HA gene of clade 7.2. To better understand the pathogenicity and transmission of the viruses, we infected chickens with 10 EID/0.1 ml GSE43 (clade 2.3.2) or CKE93 (clade 7.2) virus. Our results revealed that 6 of 7 specific-pathogen-free (SPF) chickens inoculated with GSE43 virus were dead before 7-day post-infection, but all the SPF chickens inoculated with CKE93 virus survived the infection. Both the GSE43 and CKE93 viruses replicated systemically in chickens. The virus titers of GSE43 virus in tested organs were obviously higher than those of CKE93 virus. Our results revealed that the pathogenicity and replication of GSE43 in chickens was much higher than those of CKE93. The GSE43 virus could transmit between chickens, but the CKE93 could not transmit between chickens by naïve contact. Therefore, different clades of H5N1 AIVs possessed variable pathogenicities and transmission abilities among chickens. Our study contributes to knowledge of pathogenic variations of prevalent H5N1 viruses.
Topics: Animal Structures; Animals; Chickens; China; Genetic Variation; Genotype; Influenza A Virus, H5N1 Subtype; Influenza in Birds; Phylogeny; Survival Analysis; Viral Load; Virulence; Whole Genome Sequencing
PubMed: 28770175
DOI: 10.3389/fcimb.2017.00328 -
Journal of the American Veterinary... Jun 2006
Review
Topics: Animals; Animals, Domestic; Animals, Wild; Birds; Influenza A virus; Influenza in Birds
PubMed: 16784376
DOI: 10.2460/javma.228.12.1877 -
F1000Research 2022Avian influenza virus subtype H9N2 was first documented in Indonesia in 2017. It has become prevalent in chickens in many provinces of Indonesia as a result of... (Review)
Review
Avian influenza virus subtype H9N2 was first documented in Indonesia in 2017. It has become prevalent in chickens in many provinces of Indonesia as a result of reassortment in live bird markets. Low pathogenic avian influenza subtype H9N2 virus-infected poultry provides a new direction for the influenza virus. According to the latest research, the Indonesian H9N2 viruses may have developed through antigenic drift into a new genotype, posing a significant hazard to poultry and public health. The latest proof of interspecies transmission proposes that the next human pandemic variant will be the avian influenza virus subtype H9N2. Manipulation and elimination of H9N2 viruses in Indonesia, constant surveillance of viral mutation, and vaccine updates are required to achieve effectiveness. The current review examines should be investigates/assesses/report on the development and evolution of newly identified H9N2 viruses in Indonesia and their vaccination strategy.
Topics: Animals; Chickens; Humans; Indonesia; Influenza A Virus, H9N2 Subtype; Influenza in Birds; Poultry; Vaccination
PubMed: 35844820
DOI: 10.12688/f1000research.118669.2 -
Sante (Montrouge, France) 2007Recent alerts about "avian influenza", more often referred to by veterinarians as "fowl plague" and by the public as "bird flu", and about its transmission to humans,... (Review)
Review
Recent alerts about "avian influenza", more often referred to by veterinarians as "fowl plague" and by the public as "bird flu", and about its transmission to humans, have received extensive media coverage. Physicians need further information about this development. We begin by looking at several fundamental aspects of influenza virus structure and its various types and subtypes and then review the various avian and human influenza epidemics throughout history. A description follows of the current avian influenza, its history, its presence in migratory and domestic birds, and its clinical aspects. Transmission to humans is covered next: the facts, conditions, human cases, and consumption of poultry meat. Then we consider treatment: none in animal diseases, and very limited for human disease. Vaccination has previously been dealt with and will be barely touched upon here. Finally we will present the guidelines and measures taken both nationally and internationally. Our conclusion is intended to be relatively optimistic, stressing the species barrier and the multiplicity of pathogenic avian viruses recently encountered in humans. We insist on the need to contain the epizootic, if necessary by animal vaccination, to diminish the likelihood of human contamination.
Topics: Amantadine; Animals; Antiviral Agents; Birds; Humans; Influenza A Virus, H5N1 Subtype; Influenza Vaccines; Influenza in Birds; Influenza, Human; Oseltamivir; Poultry; Practice Guidelines as Topic; Time Factors; Virulence; Virus Replication
PubMed: 17897895
DOI: No ID Found