scholarly journals The Multifaceted Zoonotic Risk of H9N2 Avian Influenza

2018 ◽  
Vol 5 (4) ◽  
pp. 82 ◽  
Author(s):  
Elizabeth Pusch ◽  
David Suarez
Keyword(s):  
Avian Influenza ◽  
Severe Pneumonia ◽  
Cell Receptor ◽  
Influenza Viruses ◽  
Effective Vaccine ◽  
Upper Respiratory Tract ◽  
Zoonotic Risk ◽  
Occupationally Exposed ◽  
Upper Respiratory ◽  
Almost All

Poultry-adapted H9N2 avian influenza viruses (AIVs) are commonly found in many countries in Asia, the Middle East, Africa, and Europe, and although classified as low pathogenic viruses, they are an economically important disease. Besides the importance of the disease in the poultry industry, some H9N2 AIVs are also known to be zoonotic. The disease in humans appears to cause primarily a mild upper respiratory disease, and doesn’t cause or only rarely causes the severe pneumonia often seen with other zoonotic AIVs like H5N1 or H7N9. Serologic studies in humans, particularly in occupationally exposed workers, show a large number of people with antibodies to H9N2, suggesting infection is commonly occurring. Of the four defined H9N2 poultry lineages, only two lineages, the G1 and the Y280 lineages, are associated with human infections. Almost all of the viruses from humans have a leucine at position 226 (H3 numbering) of the hemagglutinin associated with a higher affinity of binding with α2,6 sialic acid, the host cell receptor most commonly found on glycoproteins in the human upper respiratory tract. For unknown reasons there has also been a shift in recent years of poultry viruses in the G1 and Y280 lineages to also having leucine instead of glutamine, the amino acid found in most avian viruses, at position 226. The G1 and Y280 poultry lineages because of their known ability to infect humans, the high prevalence of the virus in poultry in endemic countries, the lack of antibody in most humans, and the shift of poultry viruses to more human-like receptor binding makes these viruses a human pandemic threat. Increased efforts for control of the virus, including through effective vaccine use in poultry, is warranted for both poultry and public health goals.

scholarly journals Pathogenicity and Transmissibility of North American H7 Low Pathogenic Avian Influenza Viruses in Chickens and Turkeys

Viruses ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 163 ◽  
Author(s):  
Ishita Roy Chowdhury ◽  
Sai Yeddula ◽  
Shin-Hee Kim
Keyword(s):  
Avian Influenza ◽  
Respiratory Tract ◽  
Broiler Chickens ◽  
Influenza Viruses ◽  
Upper Respiratory Tract ◽  
Pathogenic Avian Influenza ◽  
Recent Emergence ◽  
Specific Pathogen ◽  
Upper Respiratory ◽  
Low Pathogenic Avian Influenza

Low pathogenic avian influenza (LPAI) viruses can silently circulate in poultry and wild aquatic birds and potentially mutate into highly pathogenic avian influenza (HPAI) viruses. In the U.S., recent emergence and spread of H7N8 and H7N9 HPAI viruses not only caused devastating losses to domestic poultry but also underscored the capability of LPAI viruses to mutate into HPAI viruses. Therefore, in this study, we evaluated pathogenicity and transmissibility of H7N8 and H7N9 LPAI viruses (the progenitors of HPAI viruses) in chickens and turkeys. We also included H7N2 isolated from an outbreak of LPAI in commercial chickens. H7 viruses replicated more efficiently in the respiratory tract than in the gastrointestinal tract, suggesting that their replication is restricted to the upper respiratory tract. Specifically, H7N2 replicated most efficiently in two-week-old chickens and turkeys. In contrast, H7N8 replicated least efficiently in those birds. Further, replication of H7N2 and H7N9 was restricted in the upper respiratory tract of four-week-old specific-pathogen-free (SPF) and broiler chickens. Despite their restricted replication, the two viruses efficiently transmitted from infected to naïve birds by direct contact, leading to seroconversion of contacted chickens. Our findings suggest the importance of continuous monitoring and surveillance of LPAI viruses in the fields.

scholarly journals Serologic Evidence of Occupational Exposure to Avian Influenza Viruses at the Wildfowl/Poultry/Human Interface

2021 ◽  
Vol 9 (10) ◽  
pp. 2153
Author(s):  
Maria Alessandra De Marco ◽  
Mauro Delogu ◽  
Marzia Facchini ◽  
Livia Di Trani ◽  
Arianna Boni ◽  
...  
Keyword(s):  
Avian Influenza ◽  
Influenza Viruses ◽  
Confirmatory Test ◽  
Avian Influenza Viruses ◽  
Serum Samples ◽  
Human Interface ◽  
Zoonotic Risk ◽  
Exposed Workers ◽  
Occupationally Exposed ◽  
Human Sera

Ecological interactions between wild aquatic birds and outdoor-housed poultry can enhance spillover events of avian influenza viruses (AIVs) from wild reservoirs to domestic birds, thus increasing the related zoonotic risk to occupationally exposed workers. To assess serological evidence of AIV infection in workers operating in Northern Italy at the wildfowl/poultry interface or directly exposed to wildfowl, serum samples were collected between April 2005 and November 2006 from 57 bird-exposed workers (BEWs) and from 7 unexposed controls (Cs), planning three sample collections from each individual. Concurrently, AIV surveillance of 3587 reared birds identified 4 AIVs belonging to H10N7, H4N6 and H2N2 subtypes while serological analysis by hemagglutination inhibition (HI) assay showed recent infections caused by H1, H2, H4, H6, H10, H11, H12, and H13 subtypes. Human sera were analyzed for specific antibodies against AIVs belonging to antigenic subtypes from H1 to H14 by using HI and virus microneutralization (MN) assays as a screening and a confirmatory test, respectively. Overall, antibodies specific to AIV-H3, AIV-H6, AIV-H8, and AIV-H9 were found in three poultry workers (PWs) and seropositivity to AIV-11, AIV-H13—still detectable in October 2017—in one wildlife professional (WP). Furthermore, seropositivity to AIV-H2, accounting for previous exposure to the “extinct” H2N2 human influenza viruses, was found in both BEWs and Cs groups. These data further emphasize the occupational risk posed by zoonotic AIV strains and show the possible occurrence of long-lived antibody-based immunity following AIV infections in humans.

scholarly journals Seasonal and Pandemic Human Influenza Viruses Attach Better to Human Upper Respiratory Tract Epithelium than Avian Influenza Viruses

2010 ◽  
Vol 176 (4) ◽  
pp. 1614-1618 ◽  
Author(s):  
Debby van Riel ◽  
Michael A. den Bakker ◽  
Lonneke M.E. Leijten ◽  
Salin Chutinimitkul ◽  
Vincent J. Munster ◽  
...  
Keyword(s):  
Avian Influenza ◽  
Respiratory Tract ◽  
Influenza Viruses ◽  
Upper Respiratory Tract ◽  
Human Influenza ◽  
Avian Influenza Viruses ◽  
Upper Respiratory

scholarly journals Evolution and Adaptation of the Avian H7N9 Virus into the Human Host

2020 ◽  
Vol 8 (5) ◽  
pp. 778
Author(s):  
Andrew T. Bisset ◽  
Gerard F. Hoyne
Keyword(s):  
Amino Acid ◽  
Avian Influenza ◽  
Influenza A ◽  
Amino Acid Sequences ◽  
Influenza Viruses ◽  
Amino Acid Substitutions ◽  
Upper Respiratory Tract ◽  
Viral Polymerase ◽  
Evolutionary Changes ◽  
Avian Origin

Influenza viruses arise from animal reservoirs, and have the potential to cause pandemics. In 2013, low pathogenic novel avian influenza A(H7N9) viruses emerged in China, resulting from the reassortment of avian-origin viruses. Following evolutionary changes, highly pathogenic strains of avian influenza A(H7N9) viruses emerged in late 2016. Changes in pathogenicity and virulence of H7N9 viruses have been linked to potential mutations in the viral glycoproteins hemagglutinin (HA) and neuraminidase (NA), as well as the viral polymerase basic protein 2 (PB2). Recognizing that effective viral transmission of the influenza A virus (IAV) between humans requires efficient attachment to the upper respiratory tract and replication through the viral polymerase complex, experimental evidence demonstrates the potential H7N9 has for increased binding affinity and replication, following specific amino acid substitutions in HA and PB2. Additionally, the deletion of extended amino acid sequences in the NA stalk length was shown to produce a significant increase in pathogenicity in mice. Research shows that significant changes in transmissibility, pathogenicity and virulence are possible after one or a few amino acid substitutions. This review aims to summarise key findings from that research. To date, all strains of H7N9 viruses remain restricted to avian reservoirs, with no evidence of sustained human-to-human transmission, although mutations in specific viral proteins reveal the efficacy with which these viruses could evolve into a highly virulent and infectious, human-to-human transmitted virus.

scholarly journals Enhancing Protective Efficacy of Poultry Vaccines through Targeted Delivery of Antigens to Antigen-Presenting Cells

Vaccines ◽  
2018 ◽  
Vol 6 (4) ◽  
pp. 75 ◽  
Author(s):  
Angita Shrestha ◽  
Jean-Remy Sadeyen ◽  
Munir Iqbal
Keyword(s):  
B Cells ◽  
Avian Influenza ◽  
Targeted Delivery ◽  
Vaccine Development ◽  
Antigen Presenting Cells ◽  
Influenza Viruses ◽  
Effective Vaccine ◽  
Capture Process ◽  
Selective Delivery ◽  
Antigen Presenting

Avian viral diseases including avian influenza, Marek’s disease and Newcastle disease are detrimental to economies around the world that depend on the poultry trade. A significant zoonotic threat is also posed by avian influenza viruses. Vaccination is an important and widely used method for controlling these poultry diseases. However, the current vaccines do not provide full protection or sterile immunity. Hence, there is a need to develop improved vaccines. The major aim of developing improved vaccines is to induce strong and specific humoral and cellular immunity in vaccinated animals. One strategy used to enhance the immunogenicity of vaccines is the selective delivery of protective antigens to antigen-presenting cells (APCs) including dendritic cells, macrophages and B cells. APCs have a central role in the initiation and maintenance of immune responses through their ability to capture, process and present antigens to T and B cells. Vaccine technology that selectively targets APCs has been achieved by coupling antigens to monoclonal antibodies or ligands that are targeted by APCs. The aim of this review is to discuss existing strategies of selective delivery of antigens to APCs for effective vaccine development in poultry.

scholarly journals Insights into the Acquisition of Virulence of Avian Influenza Viruses during a Single Passage in Ferrets

Viruses ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 915
Author(s):  
Butler ◽  
Middleton ◽  
Haining ◽  
Layton ◽  
Rockman ◽  
...  
Keyword(s):  
Avian Influenza ◽  
Respiratory Tract ◽  
Severe Disease ◽  
Influenza Viruses ◽  
Mammalian Host ◽  
Upper Respiratory Tract ◽  
Avian Influenza Viruses ◽  
Single Passage ◽  
H5n1 Isolate ◽  
High Pathogenicity

Circulating avian influenza viruses pose a significant threat, with human infections occurring infrequently but with potentially severe consequences. To examine the dynamics and locale of the adaptation process of avian influenza viruses when introduced to a mammalian host, we infected ferrets with H5N1 viruses. As expected, all ferrets infected with the human H5N1 isolate A/Vietnam/1203/2004 showed severe disease and virus replication outside the respiratory tract in multiple organs including the brain. In contrast infection of ferrets with the avian H5N1 virus A/Chicken/Laos/Xaythiani26/2006 showed a different collective pattern of infection; many ferrets developed and cleared a mild respiratory infection but a subset (25–50%), showed extended replication in the upper respiratory tract and developed infection in distal sites. Virus from these severely infected ferrets was commonly found in tissues that included liver and small intestine. In most instances the virus had acquired the common virulence substitution PB2 E627K but, in one case, a previously unidentified combination of two amino acid substitutions at PB2 S489P and NP V408I, which enhanced polymerase activity, was found. We noted that virus with high pathogenicity adaptations could be dominant in an extra-respiratory site without being equally represented in the nasal wash. Further ferret passage of these mutated viruses resulted in high pathogenicity in all ferrets. These findings illustrate the remarkable ability of avian influenza viruses that avoid clearance in the respiratory tract, to mutate towards a high pathogenicity phenotype during just a single passage in ferrets and also indicate a window of less than 5 days in which treatment may curtail systemic infection.

scholarly journals Organophosphate Insecticide Poisoning and its Management

1974 ◽  
Vol 2 (4) ◽  
pp. 361-368 ◽  
Author(s):  
A. Ganendran
Keyword(s):  
Respiratory Tract ◽  
Cholinesterase Inhibitors ◽  
Upper Respiratory Tract ◽  
Organophosphate Insecticide ◽  
Agricultural Work ◽  
Home Gardening ◽  
Parathion Poisoning ◽  
Upper Respiratory ◽  
Almost All ◽  
Severe Type

The organophosphate insecticides have become widely used in agriculture and in home gardening. There has been an increase in accidental and intentional poisoning. Almost all these compounds are potent cholinesterase inhibitors, and signs of poisoning are attributable to the accumulation of acetylcholine. The local absorption of these compounds from the conjunctiva, upper respiratory tract and skin following exposure to the aerosol or dust used in agricultural work, produces mild symptoms and is rarely of consequence except in accidents due to careless handling. The severe type of poisoning is caused usually by ingestion of the compound(s), and accumulation of large amounts of acetylcholine is fatal if not antagonized rapidly by atropine in large and continuous doses, together with respiratory support. Pyridine-2-Aldoxime Methiodide (P-2-AM) has been reported to be successful in treating Parathion poisoning. There is experimental evidence that it is not of similar value in some other organophosphorus insecticide poisoning.

scholarly journals Human Infection withFusobacterium necrophorumwithout Jugular Venous Thrombosis: A Varied Presentation of Lemierre’s Syndrome

2017 ◽  
Vol 2017 ◽  
pp. 1-3
Author(s):  
Muhammad Asim Rana ◽  
Yashwant Kumar ◽  
Abdullah Ali Lashari ◽  
Ahmed F. Mady
Keyword(s):  
Nerve Palsy ◽  
Jugular Vein ◽  
Kidney Injury ◽  
Severe Pneumonia ◽  
Fusobacterium Necrophorum ◽  
Human Infection ◽  
Upper Respiratory Tract ◽  
Lemierre’S Syndrome ◽  
Upper Respiratory ◽  
Lemierre's Syndrome

Lemierre’s syndrome is also known as postangina septicemia, which is commonly caused byFusobacterium necrophorumalso known as Necrobacillus and also by other microorganisms likeStaphylococcus,Streptococcus,Peptostreptococcus, andBacteroides. Though the disease starts as an upper respiratory tract infection, it may spread and cause thrombophlebitis of the internal jugular vein. It may present itself through cranial nerve palsy or sepsis involving distant organs like the lungs or bones. It is also known as forgotten disease because of its rarity.Fusobacterium necrophorumusually causes infection in animals and rarely affects humans. We hereby present a case of Necrobacillus infection which did not cause any thrombophlebitis but resulted in severe pneumonia and acute kidney injury, leading to respiratory failure and requiring mechanical ventilation.

scholarly journals Prevention and Treatment of Influenza, Influenza-Like Illness, and Common Cold by Herbal, Complementary, and Natural Therapies

2016 ◽  
Vol 22 (1) ◽  
pp. 166-174 ◽  
Author(s):  
Haider Abdul-Lateef Mousa
Keyword(s):  
Respiratory Tract ◽  
Respiratory Tract Infections ◽  
Influenza Viruses ◽  
Carnosic Acid ◽  
Upper Respiratory Tract ◽  
H5n1 Influenza ◽  
Prevention And Treatment ◽  
Upper Respiratory ◽  
Tract Infections ◽  
Viral Respiratory

In recent years viral respiratory tract infections, especially influenza viruses, have had a major impact on communities worldwide as a result of unavailability of effective treatment or vaccine. The frequent alterations in the antigenic structures of respiratory viruses, particularly for RNA viruses, pose difficulties in production of effective vaccines. The unavailability of optimal medication and shortage of effective vaccines suggests the requirement for alternative natural therapies. Several herbal remedies were used for prevention and treatment viral respiratory illnesses. Among those that were found effective included maoto, licorice roots, antiwei, North American ginseng, berries, Echinacea, plants extracted carnosic acid, pomegranate, guava tea, and Bai Shao. There is scientific evidence regarding the effectiveness of several complementary therapies for colds. Oral zinc may reduce the length and severity of a cold. Taking vitamin C supplements on a regular basis only slightly reduces the length and severity of colds. Probiotics were found better than placebo in reducing the number episodes of acute upper respiratory tract infections, the rate of episodes of acute upper respiratory tract infection and reducing antibiotic use. Alkaline diets or drinks might have antiviral properties as in vitro studies demonstrated inactivation effect of alkaline medium on respiratory virus. Earthing might have a natural anti-inflammatory effect for human body. It is now accepted that an overwhelming inflammatory response is the cause of human deaths from avian H5N1 influenza infection. Earthing accelerates immune response following vaccination, as demonstrated by increases of gamma globulin concentration. No in vivo or clinical studies were found that investigate the role of alkalization or earthing on respiratory viral infections. Thus, future studies are recommended to reveal any potential curative effects.

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