Guidelines for avian influenza viruses select agents. There is no evidence to suggest that the consumption. Like other avian viruses of the h5 and h7 subtypes, h5n1 initially caused only mild disease with symptoms, such as ruffled feathers and. H14, h6 and h816 are not defined as avian influenza and are not notifiable. We isolated highly pathogenic avian influenza ah5n6 virus clade 2. Asian highly pathogenic avian influenza hpai ah5n1 virus occurs mainly in birds and is highly contagious among them. This report highlights global avian influenza activity in humans and birds.
The avian virus is inactivated more quickly in manure, but can survive for up to 2 weeks in feces on cages. Epidemiology, evolution, and recent outbreaks of avian influenza. These viruses occur naturally among wild aquatic birds worldwide and can infect domestic poultry and other bird and animal species. Many strains of avian influenza virus can cause varying degrees of disease in domestic poultry. Fao h7n9 situation update avian influenza ah7n9 virus. Avian influenza is a viral disease that can affect bird species throughout the world. Feb 19, 2020 emergence of avian influenza ah7n9 virus causing severe human illness may 10, 20 testing recommendations for possible h7n9 infection in us jan 24, 2014 h7n9 images. General provisions 1 for the purposes of the terrestrial code, avian influenza is defined as an infection of poultry caused by any influenza a virus of the h5 or h7 subtypes or by any influenza a virus with an intravenous pathogenicity index.
Molecular identification of avian influenza virus subtypes h5n1 and. In poultry, avian influenza viruses aivs are classified according to the. January 17, 2006 updated november 1, 2006 steven weisbart, ph. Disease outbreak news also available in arabic, chinese, french, russian, and spanish. Hpai is a fatal form of avian influenza that can spread rapidly in flocks, causing high mortalities. Summary of status of development and availability of avian influenza ah7n9 candidate vaccine. Who candidate vaccine viruses for avian influenza ah7n9. Candidate vaccine viruses for avian influenza ah7n9 who provisional recommendation on influenza ah7n9 vaccine virus as of 31 may 20. Update of the development and availability of candidate vaccine viruses for avian influenza ah7n9 pdf, 81kb 20 may 20. More than a dozen types of bird flu have been identified, including the two strains that have most recently infected humans h5n1 and h7n9. Occasionally, transmission of a highly pathogenic avian influenza virus hpaiv from infected poultry to humans results in a severe public health crisis.
Influenza type a subtype h5n1 can cause an illness known as avian influenza or bird flu in birds, humans and many other animal species. Highly pathogenic asian avian influenza ah5n1 virus. Its rapid spread to central asia, europe, the middle east, and africa in 2005 and 2006 caused legitimate concern throughout the entire world. Surveillance and analysis of avian influenza viruses, australia. Pdf influenza is an infectious respiratory disease that, in humans, is caused by influenza a and influenza b viruses. This scientific report provides an overview of highly pathogenic avian influenza hpai virus outbreaks. Timely identification of pandemic influenza threats depends on monitoring for highly pathogenic avian influenza viruses. Pandemic influenza virus has its origins in avian influenza viruses. Because these newly identified avian influenza a h5 viruses are related to avian influenza a viruses associated with severe disease in humans e. The highly pathogenic avian influenza virus subtype h5n1 caused 22. Avian influenza bird flu what is avian influenza and what causes it. Avian influenza weekly update number 735 human infection with.
A highly pathogenic avian h7n9 influenza virus isolated from a human is. Mar 21, 2019 avian influenza refers to the disease caused by infection with avian bird influenza flu type a viruses. In 2003 in the netherlands, avian influenza virus h7n7. Avian influenza report avian influenza report is a weekly report produced by the surveillance division of the communicable disease branch of the centre for health protection. Information for specific groups avian influenza flu. Highly pathogenic avian influenza virus h5n8 clade 2. Effectiveness of live poultry market interventions on. Mar 04, 2008 for those looking for a single, exhaustive reference to help educate or train individuals in dealing with avian influenza, this will be money well spent. Pdf avian influenza viruses in humans researchgate.
The type with the greatest risk is highly pathogenic avian influenza hpai. Bird flu avian influenza is a disease caused by strains of influenza virus that primarily affects birds. Hpai ah5n1 highly pathogenic avian influenza virus of type a of subtype h5n1 is the causative agent and is enzootic in many bird populations, especially in southeast asia. Avian flu healthcare workers avian flu is a viral disease and it can be very contagious and even deadly in poultry e. Selfobservation instructions for demobilizing bird flu. Pathology, molecular biology, and pathogenesis of avian. Update of who biosafety risk assessment and guidelines for the production and quality control of human influenza vaccines against avian influenza ah7n9 virus pdf, 609kb 10 may 20 updated on 23 may 20 development and distribution of. The current episode originated in southeast asia at least as far back as 1997. Avian influenza overview februaryaugust 2019 ecdc europa eu. Suppression of avian influenza transmission in genetically. It is often referred to simply as bird flu or avian influenza, even though it is only one of many subtypes. Therefore, effective vaccines against h5n1 viruses are.
Avian influenza viruses are highly contagious, extremely variable viruses that are widespread in birds, particularly wild waterfowl and shorebirds. May 21, 2016 on the other hand, in a few studies, the plant antiviral ingredients showed to be effective against the intracellular steps of enveloped viruses such as hsv1, bovine herpesvirus type 2, human immunodeficiency virus type 1, influenza a virus, influenza b virus, and human respiratory syncytial virus 11, 12, 16, 19. A virus is defined as hpai or lpai by its ability to cause severe disease in intravenously inoculated young chickens in the laboratory, or by its. Avian influenza ai, commonly called bird flu, is a disease found in some populations of wild water fowl that can infect chickens, turkeys, pheasants, quail, ducks, geese and guinea fowl, as well as a wide variety of other domesticated and wild birds. H7n9 virus isolates from 32 human cases were found to be hpai virus.
Standardization of the influenza ah7n9 virus terminology. Antiviral activity of the oseltamivir and melissa officinalis. Moderate influenza pandemic similar to 1957 and 1968 outbreaks could cost u. Low pathogenicity nonh5 and nonh7 influenza a viruses i. Influenza a viruses with high pathogenicity in birds other than poultry, including wild birds, are also notifiable.
Epidemiology of human infections with avian influenza ah7n9. The area to be disinfected must be clear of organic material, which greatly increases the resistance of avian influenza virus resistance to disinfection. Avian influenza 3 and that will spread readily from person to person is unknown. Genetic characterization of avian influenza ah5n6 virus. Avian influenza, known informally as avian flu or bird flu, is a variety of influenza caused by viruses adapted to birds. Avian influenza viruses can survive indefinitely when frozen. Moreover, h9n2 influenza viruses are considered to be one of the most important candidates for the next influenza pandemic. Collecting, preserving and shipping specimens for the. Avian influenza is a highly contagious disease of poultry that continues to spread across the globe in bird populations.
The secure food supply plans for poultry, milk, pork and beef were developed to aid producers, transporters and food processors in the event of a foreign animal disease outbreak, like high pathogenicity avian influenza hpai. Avian influenza virus can survive for 100 days in distilled water at room temperature, and 200 days at 17 c 63 f. Avian pathology the onset of virus shedding and clinical signs in. Influenza a virus causes influenza in birds and some mammals, and is the only species of the genus alphainfluenzavirus of the virus family orthomyxoviridae. The q26 and q39 viruses were both double reassortant avian influenza viruses h7 and h9 subtype, as was the early h7n9 virus figure. Interagency strategic plan for avian influenza surveillance. A novel alternative strategy is to develop chickens that are genetically resistant to infection.
Avian influenza usually does not make wild birds sick, but can cause serious illness and death in poultry footnote 10. The virus was first detected in 1996 in geese in china. How infected backyard poultry could spread bird flu to people human infections with bird flu viruses rare but possible 1direct contact most common bird flu virus touching virus and then touching the eyes, nose or mouth infection can occur without touching poultry. Of great concern are the highly pathogenic avian influenza hpai viruses e. However, this possibility combined with the increasing resistance of the h5n1 ai virus to currently available antiviral treatment and lack of complete vaccination effectiveness make this a critical human health risk. The present study described the spatiotemporal dynamics of hpai h5n1 in five nile delta. Influenza a virus highly pathogenic avian influenzah5n1 aabb. The highly pathogenic avian influenza virus subtype h5n1 is already panzootic in poultry, with attendant economic consequences. It was caused by an h1n1 virus with genes of avian origin. Ecology of avian influenza viruses in a changing world. The latter are composed of key genes from the 1918 virus, updated by subsequentlyincorporated avian influenza genes that code for novel surface proteins, making the 1918 virus indeed the mother of all pandemics. Although there is not universal consensus regarding where the virus originated, it spread worldwide during 19181919. Collecting, preserving and shipping specimens for the diagnosis of avian influenza ah5n1 virus infection guide for field operations october 2006 4 1. Pdf pandemic influenza virus has its origins in avian influenza viruses.
Interagency strategic plan for avian influenza surveillance in migratory birds the united states government is acutely aware of the threat the highly pathogenic h5n1 avian influenza viruses poses to our nations public health, agriculture industries, and economy. Interim guidance on testing, specimen collection, and. Generation of a reassortant avian influenza virus h5n2 vaccine strain capable of protecting chickens against infection with egyptian h5n1 and h9n2 viruses. Avian influenza viruses are the original source of all human influenza a virus genes. Among the avian influenza viruses, the eurasianafrican h5n1 hpai viruses are unique. Novel reassortants of h7n9, h10n8, and h5n6 avian influenza viruses aivs are currently circulating in chinas. Wild birds are recognized as the ancestral host of influenza a viruses, and avian viruses have contributed genetic material to most human viruses, including subtypes h5n1 and h1n1. Since 10 january 2017, highly pathogenic avian influenza hpai type h7n9 virus was detected in a total of 66 poultry or environmental samples 46 chickens, 8 peacocks, 2 duck and 10 environmental samples. Avian influenza virus surveillance in western alaska. We investigated carriage of avian influenza viruses by wild birds in australia. Department of agriculture usda is working with its partners on the international and domestic fronts to help control the spread of highpathogenicity h5n1 avian influenza. We detected a novel reassortant highly pathogenic avian influenza ah5n2 virus in 3 poultry farms in egypt. Avian influenza ah7n9 virus also available in chinese, french, russian, and spanish.
Protocol for laboratory testing of symptomatic responders who participated in an avian influenza outbreak response pdf, 759 kb. Nov 04, 2011 avian influenza ai is an infectious disease of birds caused by type a strain of the influenza virus. Avian influenza ah7n9 virus infection in 2 travelers. How infected backyard poultry could spread bird flu to people. Avian influenza viruses normally spread between birds. Rivm rapport 703719012 quantitative risk analysis of avian.
The disease can vary from mild to severe, depending on the virus strain involved. Phenotypic characterisation of avian influenza viruses circulating in. However, some viruses have been found to infect humans. Influenza a virus infections result in 500,000 human deaths per year and many more sublethal infections. Avian influenza viruses are inactivated by heat and drying and also these viruses are very sensitive to most disinfectants and detergents. Human and avian viruses bind to different receptors. Cambodja, indonesia and thailand few human cases of bird flu by h5n1 were confirmed. Avian influenza refers to the disease caused by infection with avian bird influenza flu type a viruses. Successful strategies in controlling avian influenza. Avian influenza viruses can persist for extended periods of time in water, although quantitative information on the subtype h5n1 is lacking. The yukonkuskokwim delta in western alaska is an important breeding ground for thousands of birds and is located in an area where multiple migratory flyways converge, providing opportunities for infectious agents, like avian influenza virus, to spread. In january 2015, british columbia, canada, reported avian influenza ah7n9 virus infection in 2 travelers returning from china who sought outpatient care for typical influenza like illness. Strains of all subtypes of influenza a virus have been isolated from wild birds, although disease is uncommon.
In collaboration with domestic and global partners, cdcs influenza division pdf icon 1. Cdc works to improve global control and prevention of seasonal and novel influenza, including avian influenza viruses, and works to improve influenza pandemic preparedness and response. Novel reassortant highly pathogenic avian influenza ah5n2. Therefore, h5n1 virus has rightly received attention as a potential pandemic threat. The 1918 influenza pandemic was the most severe pandemic in recent history. These viruses are enveloped with a segmented, negativesense singlestranded rna genome. Summary of status of development and availability of avian influenza ah7n9 candidate vaccine viruses pdf, 128kb 23 may 20. We generated transgenic chickens expressing a shorthairpin rna designed to function as a decoy that. Journal of the american veterinary medical association, march 2009 david swaynes book avian influenza is both timely and important. Highly pathogenic avian influenza h7n3 in poultry in the usa. There was no further spread, but serosurvey findings showed. Avian influenza viruses are most frequently detected from ducks anseriformes, particularly from dabbling ducks, such as mallards anas platyrhynchos. Avian influenza ai, caused by the influenza virus typea, can affect several species of food producing birds.
Jan 14, 2011 infection of chickens with avian influenza virus poses a global threat to both poultry production and human health that is not adequately controlled by vaccination or by biosecurity measures. Highly pathogenic avian influenza hpai ah5n1 viruses have been circulating since 2003 in indonesia, with major impacts on poultry health, severe economic losses, and 168 fatal laboratoryconfirmed human cases. Avian influenza viruses are classified as either low pathogenic also called low pathogenicity avian influenza viruses or highly pathogenic high pathogenicity avian influenza viruses. Update on avian influenza a h5n1 virus infection in humans. This virus has a close genetic relationship with subtype h5n8 viruses circulating in europe. Public health monitoring plan for usdaaphis responders to detections of avian influenza virus in poultry cdc pdf external. Summary pandemic influenza virus has its origins in avian influenza viruses.
This document is a supplement to fad prepnahems guidelines. We isolated highly pathogenic avian influenza virus h5n8 of clade 2. Highly pathogenic avian influenza hpai h5n1 virus is widely circulated between poultry flocks in egypt. Hong kong centre for health protection chp avian influenza page.
This document provides guidance to local, state, and federal public health authorities on monitoring of persons potentially exposed to avian influenza viruses during official united states department of agriculture animal and plant health inspection service aphis. The highly pathogenic avian influenza virus subtype h5n1 is already. Public health monitoring plan for usdaaphis responders to detections of avian influenza virus in poultry cdc pdf 325 kb, 17 pages external. Biology of avian influenza and recent outbreaks may 2015. One study 2 showed the avian influenza subtype h3n6 resuspended in mississippi. Bird flu is caused by a type of influenza virus that rarely infects humans. Department of health and human services hhs h7n9 page.
Potential transmission of avian influenza a h5n1 virus. Asian h5n1 was first detected in humans in 1997 during a poultry outbreak in hong kong and has since been detected in poultry and wild birds in more than 50 countries in. Above all else, bird flu, better named avian influenza, is an animal health problem. Enhanced surveillance to detect newly emerging viruses is warranted. Influenza a virus h5n1 an overview sciencedirect topics.
Avian influenza ai is caused by members of the genus influenzavirus a orthomyxoviridae family and is further divided into two categories. Avian influenza ai is a viral infection of domestic poultry, and pet, zoo, and wild birds. The most severe strain, called highly pathogenic avian influenza hpai, is caused by viruses with h5. Avian influenza aithe bird fluis a virus that infects wild birds such as ducks, gulls and. Avian influenza aithe bird fluis a virus that infects wild birds such as ducks, gulls, and shorebirds and domestic poultry such as. Avian influenza a h5n1 viruses are entrenched among poultry in parts of asia and africa and continue to cause disease with high mortality in humans. Avian influenza virus an overview sciencedirect topics. Avian influenza viruses and influenza in humans library. Information on avian influenza avian influenza flu. Continuing progress towards a unified nomenclature system for the highly pathogenic h5n1 avian influenza viruses march 2009.
Who provisional recommendation on influenza ah7n9 vaccine virus as of 31 may 20 pdf, 87kb 31 may 20. When avian influenza infects humans, symptoms may range from mild upper respiratory infection fever and cough to severe pneumonia, acute respiratory distress syndrome difficulty breathing, shock and even death. Avian influenza ai is an infectious disease of birds caused by type a strains of the influenza virus. Bird flu is similar to swine flu, dog flu, horse flu and human flu as an illness caused by strains of influenza viruses that have adapted to a specific host. In the late 1990s, a new strain of bird flu arose that was remarkable for its ability to cause severe disease and death, especially in domesticated birds such as ducks, chickens, or turkeys. We performed phylogenetic analysis on 39 fullgenome h5n1 virus samples collected during outbreaks among poultry in 20152016 in west java and compared them with recently published. Influenza a is caused by specified viruses that are. Pdf epidemiological study on highly pathogenic avian. It continues to cross species barriers to infect humans and other mammals, often with fatal outcomes. Pandemic influenza preparedness and mitigation in refugee and displaced populations pdf. Jan 08, 2020 avian influenza initial case investigation form pdf, 175 kb the form should be completed for any person under monitoring pum for avian influenza who develops symptoms. Pdf avian flu isolation of drugresistant h5n1 virus. The ha protein of avian influenza viruses preferentially binds to sialic acids linked to galactose by.
Data and findings from studies on other avian influenza subtypes are presented below and summarized in annex 1. Introduction highly pathogenic avian influenza hpai caused by the ah5n1 influenza subtype in animal. Although h9n2 subtype influenza a virus has been classified as low pathogenic virus, frequent outbreak of the virus with high mortality has been reported in the broiler farms 22, 23. Bird flu avian influenza symptoms and causes mayo clinic. Type b and c influenza viruses are not known to infect poultry or do not cause disease in poultry. Communication immunization with the h5n1 recombinant. In domestic poultry, ai viruses are typically of low pathogenicity lp, causing subclinical infections, respiratory disease, or drops in egg production, but a few ai viruses are highly pathogenic hp, causing severe systemic disease with multiple organ failure and high mortality. Cdc interim guidance for landfill workers in the united states disposing of poultry carcasses during outbreaks of highly pathogenic avian influenza cdc pdf 408 kb, 4 pages external. The avian influenza virus outbreak in 1997 highlighted the potential of the highly pathogenic h5n1 virus to cause severe disease in humans. Ai is a highly contagious disease and some strains can cause high mortality in poultry. Update of who biosafety risk assessment and guidelines for the production and quality control of human influenza vaccines against avian influenza ah7n9 virus. The virus carried genome segments of a pigeon h9n2 influenza virus detected in 2014, a nucleoprotein segment of contemporary chicken h9n2 viruses from egypt, and hemagglutinin derived from the 2. The highly pathogenic influenza a virus subtype h5n1 is an emerging avian influenza virus that is causing global concern as a potential pandemic threat.
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