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1. What is avian influenza? |
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Avian influenza is a disease caused by a virus which has multiple strains or types, some of which are more dangerous than others. Influenza is divided into three types: A, B and C. Type A influenza includes most human and all avian influenza viruses. Avian influenza viruses can be divided into highly pathogenic (HPAI) and low pathogenic (LPAI) strains based on its ability to cause disease in poultry. Low pathogenic avian influenza is a natural infection of waterfowl that may cause minimal to no signs of disease in domestic poultry and wild birds and is not a serious threat. Highly pathogenic avian influenza is rarely found in waterfowl, but causes severe disease in domestic poultry with a high death rate. Influenza viruses are divided into subtypes based on the two proteins, haemaglutinin (H) and neuraminidase (N), that they have on their surfaces. There are 16 recognized H types, and 9 N types, and these are known to occur in a number of different combinations - the combination that is the cause for current concern is H5N1. Only two types of avian influenza viruses, H5 and H7, are known to include highly pathogenic viruses. Not all H5 and H7 influenza viruses are highly pathogenic, but H5N1 is. This form may cause disease in chickens and some other species of birds that affects multiple internal organs and has a mortality rate that can reach 90-100 percent, often within 48 hours. The H5N1 virus is the strain of avian influenza that has infected numerous species of birds in Asia, Europe and Africa since the end of 2003. It has not been found in birds in North or South America, including the Caribbean. ![]() |
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2. Is avian influenza the same as ordinary influenza? |
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No. Influenza, commonly called 'the flu', is a contagious respiratory disease in humans which causes fever, headaches, sore throat, body aches and congestion of the nose; it occurs every year, usually in winter. It causes illness in 5 out of 100 adults and 20 out of 100 children each year; it kills between 250,000 and 500,000 people around the world every year, mostly among the elderly and the very young. Avian influenza, commonly called 'bird flu', is the general name for a form of viral disease that affects birds, particularly poultry, and can take two forms: highly pathogenic avian influenza (HPAI) and low pathogenic avian influenza (LPAI). ![]() |
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3. What is the difference between HPAI, LPAI and H5N1? |
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Avian influenza is the general term for a form of viral disease that affects birds. Highly pathogenic avian influenza (HPAI) causes severe disease in chickens and up to 100 percent mortality; low pathogenic avian influenza (LPAI) causes mild disease and little or no mortality. H5N1 is the technical term for a particularly lethal sub-type of avian influenza, and just one of tens of sub-types of the disease. H5N1 can be transmitted to humans, although this is very difficult unless they come into close contact with infected birds. Unlike seasonal influenza, in which infection usually causes only mild respiratory symptoms in most people, H5N1 infection may follow an unusually aggressive clinical course, with rapid deterioration and high fatality. Primary viral pneumonia and multi-organ failure have been common among people who have become ill with H5N1 influenza. Of the few avian influenza viruses that have crossed the species barrier to infect humans, H5N1 virus has caused the largest number of reported cases of severe disease and death in humans. In the current situation in Asia, Europe, and Africa, more than half of the people known to have been infected with the virus have died. Most cases have occurred in previously healthy children and young adults. However, it is possible that the only cases currently being reported are those in the most severely ill people and that the full range of illness caused by the H5N1 virus has not yet been defined. That said, H5N1 has proved to be much less dangerous for humans than ordinary influenza (between the end of 2004 and the end of November 2006, less than 160 people have died as a result of the disease, compared to the 250,000-500,000 people who die each year from ordinary influenza). ![]() |
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4. Why does avian influenza subtype H5N1 cause so much concern? |
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The magnitude of the most recent series of outbreaks of highly pathogenic avian influenza, which began in Southeast Asia in late 2003, is the largest and most severe on record. Never before in the history of this disease have so many countries been affected. The disease and attempts to halt its spread have resulted in the death or destruction of an estimated 250 million birds. The H5N1 virus is now considered endemic (regularly found) in many parts of Indonesia and in some parts of China, Egypt and Nigeria. Establishing control of this disease in poultry is expected to take several years. H5N1 is predominantly a disease in certain species of birds. However, the widespread persistence of H5N1 in poultry populations poses two main risks for human health. The first is the small risk of direct infection when the virus passes from poultry to humans and causes severe disease. Of the very few avian influenza viruses that have infected humans, the current H5N1 virus has caused the largest number of cases of severe disease and death, although the disease has been self-limiting. Unlike normal seasonal influenza, where infection causes only mild respiratory symptoms in most people, the disease caused by H5N1 follows an unusually aggressive clinical course, with rapid deterioration and high fatality. Primary viral pneumonia and multi-organ failure are common. Unusually, most cases of H5N1 infection in humans have occurred in previously healthy children and young adults rather than the elderly or immunologically challenged. It is not known how many unreported mild or sub-clinical infections of humans with the H5N1 virus have occurred. At the moment the virus does not appear to be able to spread readily between humans. However, a second risk, of even greater concern, is that the virus - if given enough opportunities - may change, by reassortment with human influenza viruses or by some other mechanism, into a form that is highly infectious for humans and spreads easily from person to person. Such a change could mark the start of a pandemic (a global outbreak in humans). ![]() |
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5. What is the origin of the avian influenza crisis? |
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Much of the scientific evidence suggests that domestic poultry provide a favourable environment for the entry, spread and shift to high virulence of influenza viruses, which were mostly mild and confined to waterfowl in the past. The dramatic growth in domestic poultry production is part of the explanation. The origin of the current outbreak of avian influenza can be traced to East/Southeast Asia, home to an estimated six billion domestic birds. More than half of the domestic bird population is in medium- to large-scale intensive poultry holdings where fairly strict hygiene, prevention and containment (biosecurity) measures are in place; however, a sizeable part of the poultry population remains with the smallholder sector run by an estimated 200 million farmers, each keeping 5-15 birds, mainly ducks, chicken, geese, turkeys and quail. Backyard or village poultry is characterised by scavenging birds and open coops, and is exposed to viruses carried by wild birds. Seasonal seeding of influenza viruses into backyard poultry systems by migrating waterfowl allows regular addition of new viruses to the diverse domestic poultry virus pool and may explain some of the geospatial features of regional virus distribution. However, the rapid spread of certain virus types suggests dissemination mechanisms within the poultry sub-sector itself, such as live poultry movements or transports involving infected materials such as unclean cages or dirty egg crates. The risks from live bird or 'wet' markets appear the most obvious and have in the past been incriminated as a critical risk. ![]() |
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6. Why do animal/human health problems seem to recur so quickly? |
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Densely populated livestock areas are vulnerable to the introduction and spread of infectious diseases, and this is compounded by the presence of forest reserves and open water bodies in the production area, movement of animals, contamination of lorries, feed and other supplies, and hygiene on farms, the processing chain and markets. The widespread infections of commercial poultry flocks in many countries of Asia is not a total surprise. The region is known to form an influenza epicentre where birds, other animals and humans live closely together in conditions where viruses have the greatest opportunity to pass from one species to another. A number of conditions make transmission to humans of a variety of disease agents more likely, including poor sanitation of chicken stalls in retail outlets, the proximity of markets to living areas, the absence of central slaughtering facilities, and, the practice of slaughtering chickens at the retail outlets without veterinary inspection. More in general, avian influenza outbreaks can be considered as part of the process of global change. Traffic and trade dynamics create conditions for viruses, bacteria and parasites to hitch-hike around the world, affecting people, animals and ecosystems. Climate change alters the distribution and abundance of insect vectors, and influences bird migration and livestock concentrations. Urbanization, income rise and dietary changes create an increase in the demand for animal production. Outbreaks of avian influenza, SARS, foot-and-mouth disease, classical swine fever and Rift Valley Fever are all believed to reflect instabilities in the production environment and perhaps in agro-ecology in general. FAO is studying the linkages between disease occurrence in animals and diseases of animal origin in humans and environmental change, in order to better advice on the health implications of production changes in the future. ![]() |
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7. How is avian influenza transmitted? |
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Avian influenza is most often spread by contact between infected birds and healthy birds. It may also be spread indirectly through contact with contaminated equipment and materials. The avian influenza virus is found in secretions from the nares (nostrils), mouth, and eyes of infected birds and is also excreted in their droppings. Contact with contaminated droppings is the most common means of bird-to-bird transmission, although airborne secretions are another important means of transmission, especially within poultry houses. Wild duck droppings can introduce low pathogenic (LPAI) into domestic flocks raised on range or in open flight pens. How highly pathogenic avian influenza (HPAI) is initially introduced into poultry flocks remains unclear. However, the spread of avian influenza between poultry facilities almost always results from the movement of infected birds or contaminated people and equipment (including clothing, boots, and vehicles). Avian influenza virus can also be found on the outer surfaces of egg shells (but rarely inside); therefore, egg transfer is a potential means of avian influenza transmission. Airborne transmission of avian influenza virus from farm to farm is not likely. H5N1 HPAI can be spread from birds to people as a result of direct contact with infected birds, such as during home slaughter and plucking of infected poultry. Public health concerns centre around the potential for the virus to mutate or combine with other influenza viruses to a form that could easily spread from person to person. If that happens, there is a risk that the virus could rapidly spread worldwide and cause large numbers of humans to become ill or die (a pandemic). ![]() |
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8. Is there a difference between transmission and spread of avian influenza? |
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Yes. The transmission of avian influenza refers to the passing of the disease from one animal to another (and in very limited cases from an animal to a human). The spread of avian influenza refers to the wide diffusion (geographically or throughout production and market systems) of the disease among a large number of animals. Transmission From what we know today, the avian influenza virus can be transmitted through contact among and with poultry and their droppings, feathers, intestines and blood. The greatest risk of infection for humans appears to be through the handling and slaughtering of live infected poultry. Spread Unlike some diseases, avian influenza is not an air-borne disease. Most current evidence suggests that the virus spreads mainly through the movements of poultry, poultry products, people and the vehicles they use for transport. ![]() |
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9. What role does the movement of poultry play? |
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Most outbreaks of avian influenza can be linked to movements of poultry, poultry manure, poultry by-products and accidental transfer of infected material such as bird droppings, bedding straw or soil on vehicles, equipment, cages or egg flats, clothes and shoes. Worldwide, unregulated movement of poultry is the most important way that the disease is spread. Live animal or 'wet' markets may have played a major part in sustaining the virus in Southeast Asia, They were identified as the source of the H5N1 infection in chicken farms in Hong Kong in 1997 when approximately 20 percent of the chickens in live poultry markets were found to be infected. The same situation occurred in Viet Nam, where the circulation of H5N1 in geese in live bird markets in Hanoi had been documented three years before the 2004 outbreaks on chicken farms. There is also a huge international trade in poultry - both legal and illegal. The legal trade involves millions of hatching eggs and poultry being shipped to destinations worldwide; information on the extent of the unregulated and illegal poultry trade is scarce but interceptions in recent years indicate lapses in border controls despite the risk. The widespread illegal trade in ornamental, sporting and caged birds has also transported H5N1-infected birds over large distances. One of the most likely sources of infection in captive birds in Asia is again in 'wet' markets, where domestic and wild-caught birds are kept in close proximity, posing a risk of cross-contamination. ![]() |
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10. Are poultry droppings dangerous? |
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Poultry droppings could be dangerous for other animals and for people because infected poultry excrete the H5N1 virus (and other potentially dangerous pathogens) in their droppings. It is impossible to avoid other chickens coming into contact with droppings from infected chickens in the same flock, but you can protect different species by keeping them in separate enclosures. Wild ducks often introduce low pathogenic avian influenza into domestic flocks raised on range or in open flight pens through faecal contamination. Low pathogenic avian influenza naturally occurs in wild birds and can spread to domestic birds. In most cases it causes no signs of infection or only minor sickness in birds. You can protect your birds by using screens or nets to keep them separated from wild birds and their droppings. If your birds come into contact with wild birds, be sure to watch for signs of highly pathogenic avian influenza in them such as breathing problems, watery diarrhoea, swelling around the head, neck and eyes, and a drop in egg production or malformed eggs. A loss of appetite might also occur in birds. Poultry droppings are also widely used in agriculture and aquaculture as fertiliser and food for other animals such as pigs and fish. However, untreated droppings can be a significant way of passing on the disease. Even the collection and transport of untreated or non-composted poultry manure could be a highly effective way of spreading the virus. People can come into contact with poultry droppings in two ways: directly through their skin and indirectly through clothing or equipment. Always try to wear gloves, boots and other protective clothing if you are going to be in places where poultry are kept (or have been kept recently) such as enclosures, coops, sheds or other buildings. When you leave, take your gloves, boots and protective clothes off and wash your hands thoroughly with soap (or scour them vigorously with ash if no soap is available), disinfecting them afterwards if possible. It is even more important to wash and disinfect thoroughly if you have not been wearing gloves or other forms of protection. ![]() |
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11. How long does the virus live in bird/animal droppings? |
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It depends on the amount of virus contained in the droppings, temperature and moisture content. Generally speaking however, the virus dies more quickly in higher temperatures and the drier the droppings are.
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12. Could highly pathogenic H5N1 avian influenza cause a problem in countries which are currently unaffected? |
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Yes, the possibility of HPAI H5N1 breaking out always exists but the likelihood of it happening varies from country to country. This largely depends on the level of biosecurity in place on farms and in commercial poultry production facilities, on the safeguards in place to monitor disease in poultry flocks, and on the level of compliance with import and export controls. Everyone, including pet owners, should be aware of the potential of the H5N1 avian influenza virus to cause disease and death, as well as how it can be transmitted. If H5N1 HPAI is identified in your country, the competent authorities will issue instructions on the precautions to take, but there is no reason to abandon cats, dogs, or other pets because of concerns about contracting or spreading the virus. ![]() |
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13. Does avian influenza pose a threat for people? |
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Although H5N1 can cause serious disease in people, the virus is "hard to catch". Transmission from birds to human remains difficult, usually involving prolonged and close contact, and so far the virus has not been shown to spread from person to person. In the last 100 years there have been at least three major pandemics of human influenza A, which killed many people around the world. The origins of these deadly virus strains remain uncertain, but at least two are thought to have arisen when avian influenza and human influenza viruses came together, possibly in pigs, and reassorted their genetic material. Continued outbreaks of H5N1 increase the chances of this happening again, especially as the current strain of H5N1 is exceptional in that it can (though rarely does) pass directly from poultry to humans. Almost always, human infections have occurred in people who have been closely associated with poultry. Given the substantial number and distribution of outbreaks in domestic poultry and waterfowl, there have been relatively few cases in people (WHO statistics up to 29 November 2006 indicate 258 confirmed infections, with 154 fatalities), indicating that the transmission of the virus from poultry to people remains inefficient. For the latest WHO statistics on people affected, see http://www.who.int/csr/disease/avian_influenza/country/en ![]() |
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14. How do people become infected with avian influenza? |
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We do not know for certain, but direct contact with infected poultry, or surfaces and objects contaminated by their droppings is presently considered the main route for infection of humans by the avian H5N1 virus. To date, most human cases have occurred in rural or urban fringe areas where many households keep small poultry flocks, which often roam freely, sometimes entering homes or sharing outdoor areas where children play. As infected birds shed large quantities of virus in their droppings, opportunities for exposure to infected droppings or to environments contaminated by the virus are abundant under such conditions. Moreover, because many households depend on poultry for income and food, families sometimes sell or slaughter and consume birds when signs of illness appear in a flock, rather than disposing of the birds safely, and this practice has proved difficult to change. Exposure is considered most likely during slaughter, plucking and butchering. There is no evidence that properly cooked poultry or eggs can be a source of infection.
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15. Could avian influenza become an influenza pandemic? |
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Yes, but even though the H5N1 virus may have the potential to change into a virus that can easily pass from person to person, there is no evidence that this has happened. An influenza pandemic is a rare event and has occurred only three times over the last 100 years (in 1918 with around 50 million deaths, in 1957 with almost two million deaths, and in 1968 with about one million deaths). It is impossible to calculate the risk of a human pandemic. The H5N1 avian influenza virus meets two out of three conditions necessary to cause a human pandemic. It can infect humans and it causes serious illness, but critically it does not spread easily and sustainably between humans. If this virus subtype changes to spread easily and sustainably between humans it may have the capacity to cause a pandemic, but we cannot predict if, when or where this will happen. Nor can we predict whether the virus would retain its ability to cause serious disease. But we can take precautions to protect humans and we can take action where avian influenza is identified in poultry. ![]() |
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16. What should be done when an outbreak occurs? |
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The specific actions to be taken with regard to controlling marketing, imposing movement restrictions or quarantine measures, culling and vaccinating vary according to local circumstances and from country to country. There is no one solution for all situations, and a balance must be established among effective, feasible and socially acceptable control measures that safeguard the short- and long-term livelihoods of farmers and the health of the population. In general however, a number of basic measures are common to all situations: infected birds and those in contact with them must be humanely and safely culled to halt spread of the disease, levels of prevention and containment (biosecurity) must immediately be raised appropriate to the level of risk, and surveillance must be increased and widened to permit earlier detection and reporting of disease. ![]() |
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17. What precautions should be taken in a country affected by avian influenza? |
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Report sick or dead birds to the local veterinary (or public health) authorities. If this is not possible, tell your neighbours or community leaders. It is important that all signs of illness or sudden and unexplained deaths in poultry and wild birds are reported to the authorities so that they can deal with them safely and help stop the virus spreading. Keep all birds separate from people and living areas. Close contact with infected birds can put you and your family at risk. Keep wild birds away from poultry and keep different types of bird apart. Screens, fencing or nets cvan be used to separate species and help prevent transmission. Wash your hands often to kill and remove the virus. You should always do so after handling birds, cooking or preparing poultry products, and before eating. Eat well-cooked poultry products. Do not eat sick or dead chickens and do not give or sell them to others. Keep chicken from infected flocks out of the food chain and do not feed them to other animals. Seek immediate treatment from your doctor if you have fever after being in contact with sick or dead poultry. ![]() |
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1. Why is there so much concern about the current outbreaks? |
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There is concern that the virus may change (reassort or mutate) to emerge as a new virus that is easily transmissible between people and capable of causing disease in people, birds and other animals. Influenza A viruses occur worldwide in a wide range of animals, including humans. The high pathogenic H5N1 avian influenza strain involved in most of the outbreaks during the last 18 months has shown the ability to jump the species barrier occasionally and cause severe disease, with high fatality, in humans. It has not shown the capacity to transmit between humans. Avian and human influenza viruses can exchange genetic material when a person or other animal susceptible to infection is simultaneously infected with these viruses. This could create a completely new subtype of the influenza virus to which few, if any, humans would have immunity and which might be able to spread between humans. ![]() |
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2. I have heard avian influenza will kill millions of people - is this true? |
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No. Avian influenza is primarily a disease of birds. It is caused by influenza viruses closely related to human influenza viruses. Transmission to humans in close contact with poultry or other birds occurs rarely and only with some strains of avian influenza. There is potential for mutation of avian influenza viruses to new forms of virus that could cause severe disease in humans. It is also possible that a previously unknown deadly virus with the capacity to spread easily from person to person could appear. However, there has been a limited number of cases in which there has been evidence to suggest person-to-person transmission and to date there is no evidence that the highly pathogenic avian influenza virus has adapted to spread easily in humans. ![]() |
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3. Can we vaccinate people against H5N1 |
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Currently, no. There is no vaccine to protect people against H5N1 influenza infection or disease, although research is under way to find a safe and effective vaccine for human use. There is however evidence that most, but not all, H5N1 viruses respond to antiviral drugs if taken immediately or soon after infection has started.![]() |
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4. Is it safe to eat poultry and poultry products? |
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Yes, but certain precautions should always be followed to ensure that the meat and animal products we eat come from healthy animals. Poultry and other birds that have been ill and died should not be eaten nor given as feed to other animals. Only consume meat or products from healthy birds. In areas free of the disease, poultry and poultry products can be prepared and consumed as usual (following good hygienic practices and proper cooking), with no fear of being infected by the H5N1 virus. In areas experiencing outbreaks of HPAI, poultry and poultry products can also be safely consumed provided they are properly cooked and properly handled during food preparation. Consumers need to be sure that all parts of the poultry are fully cooked (no "pink" parts) and that eggs are properly cooked (no "runny" yolks); this kills not only the virus but also other important disease-causing microbes. In areas affected by the H5N1 virus, certain customary practices such as drinking raw blood or raw embryonating eggs should be discouraged if not prohibited. It is always a good idea to wash the outer surface of eggs with water and some soap to remove any dirt or faecal matter before storing or using. Also, remember that raw eggs used as an ingredient in sauces, cakes or other foodstuffs are always a potential source of disease-carrying microbes. Consumers should also be aware of the risk of cross-contamination. When preparing food, juices from raw poultry and poultry products should never be allowed to touch or mix with items eaten raw. When handling raw poultry or raw poultry products, persons involved in food preparation should wash their hands thoroughly and clean and disinfect surfaces in contact with the poultry products. It is sufficient to use soap and hot water. Avian influenza is not transmitted through cooked food. To date, no evidence indicates that anyone has become infected following the consumption of properly cooked poultry or poultry products. ![]() |
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5. Is it safe to pick up or handle feathers? |
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Yes. The probability of humans being infected with avian influenza directly from birds is extremely low (even though there have been cases of villagers in Azerbaijan who reportedly contracted the disease after plucking feathers from dead infected swans). To be on the safe side, children should not pick up or handle feathers or dead birds. If they come into contact with birds in an area not affected by HPAI, it is always wise for them to wash their hands properly.
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6. Is it safe to hunt? |
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All hunters should avoid indiscriminate killing or poaching of wild birds, not just because of the risks associated with avian influenza but as a matter of common sense and respect for legislation governing hunting. When hunting, they need to be careful about good hygiene, particularly if hunting in areas currently infected by HPAI. In addition, however, there are a number of good practices to follow which can help limit any potential increase in the risk of helping spread the virus:
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7. Can I get avian influenza from handling wild birds? |
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The risk of transmission of either LPAI or HPAI from wild birds to the general public is small. However, to minimise any risk it is advisable to carry out general hygiene precautions when handling wild birds, such as wearing disposable protective gloves when picking up and handling carcases and washing hands, nails and forearms thoroughly with soap and water after handling the carcass.
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8. What should be done if a dead bird is found? |
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Do not touch any dead animals. Report the finding to the local veterinary or public health authorities who will take the appropriate step to remove the bird and arrange for an autopsy to determine the cause of death.
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9. Is it safe to feed garden birds? |
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Feeding garden birds is completely safe provided simple common sense rules are followed. These include avoiding touching carcasses of wild birds and washing hands after filling or cleaning bird feeders. Both measures are advisable not just in the case of H5N1 but because birds can carry other potentially dangerous pathogens. If in doubt, consult your nearest vet.
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10. Is birdwatching safe? |
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Yes. The risk of being infected by wild birds is extremely low. However, it is advisable to avoid sites where there have been known cases of HPAI and - as always - it is important to use common sense and proper hygiene. Avoid touching wild birds, their droppings or water near them, and wash your hands before eating or smoking and after any contact with animals. Never pick up sick or dead animals.
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11. Should people avoid travelling to countries affected by HPAI? |
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There is no reason not to travel affected countries but, once there, it is unwise to visit poultry farms, bird markets and other places where live poultry are kept. If in doubt, consult your embassy or consulate of the country to be visited to find out if the local authorities have placed any restrictions on travel.
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12. What can travellers do to avoid bringing the disease back to their country? |
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While out of the country: Avoid visiting areas where you may come into contact with live birds, such as poultry farms, live bird markets or any other area where birds congregate. This is most important in countries experiencing an outbreak of high pathogenic avian influenza (an updated official list of countries affected by HPAI can be found at the World Organisation for Animal Health (OIE) web site at http://www.oie.int/eng/en_index.htm. If you are in contact with live birds infected with the avian influenza virus, the virus may persist on clothing, footwear and in hair. Take appropriate personal hygiene measures including thorough hand washing and showering, wash clothing, and clean and disinfect footwear to ensure they are free of soil and manure. Before returning: Find out from your country's veterinary authorities if any birds or poultry products you intend bringing back are eligible for import. On arrival, declare all such birds or poultry products. On returning home: Avoid visiting poultry farms upon return from a country affected by HPAI until you have bathed and changed clothes and footwear. ![]() |
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1. What part do wild birds play in the spread of avian influenza? |
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We do not know the whole story. Wild waterfowl, e.g. ducks and geese, are considered to be a natural reservoir for all type A influenza viruses and have probably carried them without apparent harm for centuries. There is evidence that suggests that wild migratory birds can transmit avian influenza to domestic poultry, however there is no direct evidence as to their role in H5N1 yet and active monitoring of the wild bird population will soon give us more evidence on these uncertainties. It is unlikely that wild birds play a major role in spreading avian influenza. The spreading, or wider distribution of the disease, takes place within flocks or sizeable numbers of poultry and is influenced more by production and marketing practices. ![]() |
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2. Can wild birds transmit avian influenza to humans? |
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The risks to human health from wild birds carrying avian influenza is extremely low. Apart from a few cases of villagers in Azerbaijan who reportedly contracted the disease after plucking feathers from dead infected swans, there have been no confirmed cases of transmission from wild birds to humans.
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3. If wild birds are at least partly responsible for transmitting H5N1 avian influenza, is culling part of the solution? |
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No. Attempts to control the spread of H5N1 by culling large numbers of wild birds are not recommended because:
No existing culling technique can kill sufficient numbers of wild birds as quickly as possible to avoid repopulation by birds from elsewhere, and these newcomers either come into contact with existing pockets of infection or bring it in themselves. Most killing techniques involve severe disturbance (e.g. shooting, trapping or explosives) and allow varying numbers of surviving birds enough time to move elsewhere. It is difficult to monitor and control these survivors. Without clear information on where they go, any form of violent culling may well worsen the problem. Less violent methods, such as chemical (poison) culling, may not displace significant numbers of birds but they often have serious side effects such as environmental contamination or the killing of non-targeted wildlife because of the unselective nature of the killing. There is also the question of the benefits wild birds bring to many economies and societies in terms of pest control, hunting, tourism and bird watching, as well as cultural and spiritual value. Loss of these benefits would have to be added to the high costs of attempting to control avian influenza by culling wild birds. ![]() |
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4. Should wetlands be drained to deter wild birds that congregate near or on water? |
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No. In the first place the absence of water would only force the wild birds to seek alternative points on migratory routes and could thus help carry any virus to new locations. Second, wetlands have a very high value for ecosystems, providing vital services such as flood control, water purification and recycling of nutrients. Third, many communities depend on wetlands for their livelihoods.
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5. What kinds of wild birds carry avian influenza viruses? |
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Most avian influenza viruses have been isolated from wild waterfowl (ducks, geese, and swans) and shorebirds (wading birds), gulls, and terns. With rare exceptions, the thousands of influenza isolates found in wild birds have been low pathogenic avian influenza and have rarely caused signs of illness in wild birds.
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6. Do migratory birds carry the virus from one country to another? |
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The role of migratory birds in the transfer of the Asian H5N1 strain is not clear. H5N1 has been identified in an increasing number of wild birds. The pattern and timing of several outbreaks have not coincided with periods of major migratory movements or migratory routes. However, there are also reports of wild bird mortality that are associated with outbreaks of highly pathogenic avian influenza (HPAI) H5N1 in poultry. It is not known if wild birds were the source of the virus or acquired the virus from poultry; however, once infected, they could be a potential source of infection for domestic poultry that are not properly prevented from coming into contact with wild birds.
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7. Can other wild animals be infected with avian influenza? |
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Avian influenza typically affects species of food producing birds (chickens, turkeys, quail, guinea fowl, etc.), as well as pet birds and wild birds. Studies have shown that a small number of mammalian species, including pigs, seals, whales, mink and ferrets, are susceptible to infection with avian influenza viruses. Some carnivore species such as tigers, leopards and stone martens have also been infected after eating infected chicken carcasses.
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8. What should I do if I find sick or dead wild birds? |
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It is natural to find dead birds on occasion, and the cause is most usually cold weather, starvation or fatal injury. However, if you come across incidents that appear abnormal (such as more than one dead bird within a very limited range) report the incident as soon as possible to the appropriate authorities (such as the veterinary service or the local police).
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1. Can cats, dogs and other domestic pets be infected with avian influenza? |
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Cats can be susceptible to avian influenza viruses, and research in cats has shown that H5N1 can be transmitted from cat to cat. Do not feed infected, sick or dead chickens to cats or other animals. Dogs have also been infected, but the probability of H5N1 infection in pet animals is low.
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2. People keep birds for a variety of reasons (hobby, sport, religious practices, cultural tradition, etc.) - what, if anything, should they do? |
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People who keep birds need to increase their vigilance to match the global risk. All keepers of birds should be vigilant about the health of their birds. They should also start to plan how they intend to isolate their birds in the event of an emergency. Local veterinary authorities (or their local equivalent) should be approached for advice on appropriate measures.
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3. I have a small number of chickens in my garden - do I have to be able to house them? |
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Yes - if there is an outbreak of HPAI in the area, all keepers must be ready to house their birds. All possible efforts must be taken to house or isolate your poultry from wild birds and ensure that proper hygiene/biosecurity is practised when entering or leaving the housing in which chickens are kept. It is the responsibility of bird keepers to ensure the welfare of their birds. If this proves too difficult and your birds are still healthy, you may consider butchering the birds before the disease comes to your garden.
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1. What should I do if I find a dead bird? |
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Generally speaking the finding of a single dead bird is no cause for concern - birds die all the time from natural or routine causes. However, if you come across significant numbers of dead birds at unusual times of the year or in unusual spots, you should report the finding to the veterinary or health authorities (or local equivalent) who will take the appropriate step to remove the birds and arrange for autopsies to determine the cause of death. In the meantime, avoid touching the carcasses. ![]() |
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2. Do I run a risk if I touch dead birds? |
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Wild birds can carry several diseases that are infectious to people. If dead birds are handled, it is important to wash your hands with soap and water as soon as possible. Avoid touching your face and certainly do not eat or smoke until you have washed your hands. Clean any soiling on clothing with soap and water.
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3. What am I at risk from in birds? |
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Although the risk of catching influenza from a bird that has avian influenza may be low, birds can carry other infections which can cause gastrointestinal upsets in humans such as Salmonella and Campylobacter. It is always advisable therefore to observe common standards of personal hygiene. This is particularly important when handling birds in the preparation of food.
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4. What should I do if I find several dead wild birds near or among my poultry? |
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Report without delay to your local veterinary authorities (or local equivalent). They will take the necessary action and advise on what to do next.
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5. Is it necessary to report deaths in birds kept in outside aviaries or in game birds? |
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You should only report cases where a number of birds have died within a short time and there could have been contact with migratory waterbirds.
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6. Do I have to worry about pets eating or bringing dead birds into the house? |
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It is always sensible to prevent pets eating wild bird or other animal carcasses or carrying them around because the deaths could have been caused by poisoning or a severe bacterial infection.
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7. My cat/dog found some dead birds but did not eat them - does this mean it will get avian influenza? |
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In the unlikely event that the dead birds had died from avian influenza, the risk to other animals would be extremely low.
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1. What are the signs of HPAI in poultry? |
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The severity of signs depends upon the strain of virus and the type of bird infected. Birds infected with highly pathogenic avian influenza may die suddenly or show a range of clinical signs including respiratory difficulty, diarrhoea, swollen heads, dullness, a drop in egg production, and a loss of appetite. Some birds, especially waterfowl, can be infected with low pathogenic avian influenza without showing any signs of disease. Any the following signs (either alone or together) could indicate that your poultry is affected by avian influenza:
Many of these signs could also indicate Newcastle disease, so you should seek veterinary advice to establish the exact nature of the disease affecting your poultry. The veterinarian should take samples or even a few birds for further analysis to a laboratory. You should not sell or move the birds from their houses or coops. If you do so, you may face a severe fine or, even worse, spread the disease to other areas. ![]() |
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2. Can animals "shed" the virus before clinical signs are observed? |
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The incubation period is the time between infection and the appearance of signs of disease. "Shedding," as it applies to viruses, means that the animal's secretions and/or droppings contain viral particles that may infect other animals or people. Some animals (e.g., growing poultry) rapidly show clinical signs of disease and simultaneously shed virus. Other infected animals, including some species of waterfowl, may appear clinically healthy, but be shedding the virus. The incubation and shedding periods for avian influenza virus in many species are not known.
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3. What can farmers and other poultry handlers do to protect birds? |
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One of the most common breaks in biosecurity for many transboundary animal diseases, including HPAI, is people bringing contaminated materials and equipment (clothes, shoes, transport, crates, trays, feeders, cages, etc.) or animals into areas where healthy animals are kept, or taking such materials or sick animals out of areas that are infected. Avian influenza viruses can enter or leave places where poultry are housed in three major ways: through people, through materials and through animals themselves. Prevent contamination via people
Prevent contamination via materials
Prevent contamination via animals
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4. How can farmers prevent wild birds from bringing infection to their farm? |
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Wild bird populations, a natural reservoir for the influenza viruses, are beyond the control of farmers. Therefore, it is essential for poultry farmers and producers to maintain strict biosecurity practices to prevent introduction of the virus in their flock:
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5. Is avian influenza connected to Newcastle disease? |
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No. Avian influenza is different from Newcastle disease and is caused by a totally different virus, although affected chickens may show similar signs and lesions.
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6. What is the most effective way of containing the avian influenza virus? |
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The most effective means of containing the avian influenza virus is to ensure adequate biosecurity at all stages of the poultry production and distribution cycle. One key element of biosecurity is to eliminate contact between poultry and wild birds in order to reduce the risk of wild birds passing on the virus to poultry, but also of the virus escaping from infected poultry into the wild. This is particularly important to prevent the genesis of highly pathogenic strains of avian influenza virus because scientific research has shown that some low pathogenic strains of avian influenza virus carried by wild birds have mutated into a highly pathogenic strain in poultry operations.
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7. What can be done to limit spread of the disease? |
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Avian influenza usually spreads when live birds carrying infection are bought and sold, and through bird droppings on dirty equipment, cages, feed, vehicles or shoes/clothing. Practising good hygiene (biosecurity) is therefore an extremely important safety measure to prevent infection entering domesticated poultry. Once HPAI has been recognised in a trading environment or country, all persons working with poultry should greatly increase the level of safe hygienic practices to avoid bringing the virus in (bio-exclusion) or allowing the virus to leave (bio-containment) if it has already entered a flock, village or region. The main ways in which virus can enter an area are:
The main ways in which virus can leave an area are:
The basic principle of bio-exclusion is to be aware of the various routes by which virus can enter and maintain a high level of vigilance on these routes until the period of risk is over. The basic principle of bio-containment is to keep infection within poultry units, thereby reducing risk to neighbouring flocks, villages, zones and regions, and cooperate with the authorities in disease response measures. ![]() |
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8. What are the best methods of decontamination? |
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Soapy water and detergents are the first choice because the avian influenza virus is more simple to destroy than many viruses: it is very sensitive to detergents which destroy the fatty outer layer of the virus, and this layer is needed to enter cells of animals. Water alone may be insufficient because the virus survives well in water and simple washing may only help it enter areas where it can be picked up by other birds. For extra protection it is advisable to use disinfectants, particularly in areas known to be affected by avian influenza. Disinfection helps prevent the mechanical spread of disease agents from one location to another by people, equipment and or supplies. Before leaving a site, adequately dispose of non-reusable materials, and disinfect clothes and boots and all equipment to the extent possible. Care should be taken to decontaminate all objects that have come in contact with potentially infectious materials, e.g., surgical instruments, clothing, cages, restraint or capture equipment, vehicles, boots, etc. One of the more difficult organic materials to disinfect and dispose of is bird droppings: the virus is maintained in moist, dirty conditions so it is essential to thoroughly disinfect items (such as cages, shoes and clothes) that have been in contact with these droppings before working with poultry or entering a place where poultry are kept. Click here for a table with guidance for veterinary officers and others coming into direct with poultry on the selection and application of decontamination procedures - remember that adaptation to specific country circumstances will always be necessary. ![]() |
9. What measures should be taken to protect poultry workers if avian influenza is suspected or confirmed on a poultry premises? |
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Employers must provide their employees who have had, or are likely to have contact with infected birds with information as to how to protect themselves and their families from infection. A hierarchy of control measures is likely to be required that include:
For more information, consult FAO's Protect Poultry - Protect People on this site, or the following sites: Protect Yourself - Poultry Employees, US Department of Labor, Occupational Safety & Health Administration (refers to the United States but applicable to all locations) http://www.osha.gov/OshDoc/data_AvianFlu/poultry_employees.pdf Protecting Poultry Workers at Risk (Safety and Health Information Bulletin, 13 December 2004), US Department of Labor, Occupational Safety & Health Administration (contains useful information for poultry workers everywhere) http://www.osha.gov/dts/shib/shib121304.html ![]() |
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10. How can I avoid spreading avian influenza? |
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You can help limit spread of disease by adopting safe practices in how you look after your poultry, how you look after where they live, and how you look after the equipment you use.
Looking after your poultry
Looking after where your poultry live
Looking after the equipment you use
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11. What should I do with sick poultry? |
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Isolate the sick bird(s) from the rest of the flock, then report immediately to the nearest veterinary authorities (or local equivalent). Do not move sick poultry and follow the instructions of veterinary officials. Remember to use gloves when handling sick poultry.
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12. What should I do with dead poultry? |
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Do not leave dead animals lying around. If you have a plastic bag, place the carcass in the bag; if you do not, take the carcass away from the rest of the flock and out of reach of children and other animals. Remember to use gloves when handling dead poultry. Do not throw carcasses into rivers, lakes or other bodies of water, and do not feed them to dogs, cats or other animals. After taking care of your dead birds, report immediately to the nearest veterinary authorities (or local equivalent). Leave disposal of the carcasses to these authorities and help only if they ask. If there are no local veterinary authorities, inform the town/village administration office (mayor, prefecture, etc.). Remember that you should never eat dead birds that were sick nor sell them to others. ![]() |
13. What should I do if I have to dispose of dead poultry by myself? |
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Get rid of carcasses safely by burning them or burying them away from your farmyard and deeply enough so that dogs, cats and other scavengers cannot reach them. You should also make sure that you burn or bury feathers and other waste (droppings).
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14. Can I use droppings from sick or dead birds as manure? |
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It is better not to use these droppings unless they have been composted for several weeks before applying on fields.
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15. What should I do during an outbreak of HPAI? |
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The most important precaution is to avoid continuous close contact with poultry. Above all, poultry should never be kept under the same roof as people. Otherwise, take all personal hygiene precautions such as wearing protective clothing (gloves, aprons, boots, etc.) when handling poultry and washing thoroughly after handling poultry. In an outbreak situation, children and pregnant women may be at higher risk than others, so it is wise to stop children from playing with or near poultry and not allow them to touch/pick up feathers, and to keep both children and pregnant women away from poultry and not allow them to collect eggs. The avian influenza virus survives well in water, so it is good practice to boil or otherwise treat water collected from ponds, wells or other places where poultry (or wild birds) may have drunk or left droppings. Similarly, swimming in water visited by poultry (or wild birds), such as lakes or rivers, should be avoided. Clean all farm equipment every day and, when working or sweeping the yard, cover nose and mouth with a face mask. After work, remove shoes outside the house and clean them thoroughly after removing any mud or dust. If you have to slaughter infected poultry:
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16. Given the uncertainty surrounding avian influenza, can I continue selling/buying poultry? |
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Providing you have not received instructions to not sell poultry, you can continue selling provided you respect the following recommendations:
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17. What is all in-all out poultry management? |
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In brief, selling all your poultry at the same time and buying all new birds in one batch. All in-all out refers to the practice of introducing new animals and equipment or feed only once production has started in order to lessen health risks to growing broilers, then removing all animals and sending them to the market or slaughter-house once the age for marketing is reached. This allows workers to clean, aerate, remove old feed and disinfect premises prior to the entry of new and highly susceptible chicks. This cycle is continuous and provides regular points in time for the necessary veterinary care, feed delivery, transportation entry, employee inputs, etc. If a disease enters a flock, the all in-all out process offers an already established cycle of introduction, removal, cleaning and disinfection that can be quickly implemented with little down time for farmers or producers. ![]() |
The UN system | ||
1 | How is the UN system organised to combat HPAI? | |
2 | Where can I find more information about animal and human-related aspects of avian influenza? |
1. How is the UN system organised to combat HPAI? |
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The principal international agencies concerned with animal and human health - FAO, OIE and WHO - all have individual programmes to combat avian/human influenza. UN agencies also work together under the umbrella of a mechanism known as the UN System Influenza Coordination (UNSIC), under a UN System Influenza Coordinator. The mechanism is guided by a Steering Committee, chaired by the Deputy Secretary-General of the United Nations, which sets policy and guidance for a coordinated response by the UN system, and provides advice to the UN Secretary-General. The members are the Chair of the UN Development Group (UNDG) and Administrator of UNDP, WHO, FAO, DPKO, OCHA, UNICEF the UN Department of Safety and Security, the UN Department of Management and the UN Medical Service. A Technical Working Group supports the Steering Committee and manages the coordinated efforts of the United Nations. The Technical Working Group is led by the UN System Senior Coordinator who reports to the Steering Committee through the Chair of UNDG. The Senior Coordinator is also a member of the Steering Committee ![]() |
2. Where can I find more information about animal and human-related aspects of avian influenza? |
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There are three lead agencies in the fight against avian influenza - the Food and Agriculture Organization of the United Nations (FAO), the World Organisation for Animal Health (OIE) and the World Health Organization (WHO). All three have specialised websites offering the latest information and statistics on avian influenza: Food and Agriculture Organization of the United Nations (FAO) - coordinates the global response to outbreaks of highly pathogenic avian influenza in animals http://www.fao.org/avianflu World Organisation for Animal Health (OIE) - monitors the world animal health situation and sets standards for the control of animal diseases, diagnostic tests and veterinary vaccines http://www.oie.int/eng/avian_influenza/home.htm World Health Organization (WHO) - coordinates the global response to human influenza cases related to avian influenza and monitors the corresponding threat of a human influenza pandemic http://www.who.int/csr/disease/avian_influenza/en/index.html ![]() |