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While avian influenza has been confirmed in 20 states, Alabama remains free of the disease and Alabama poultry producers are doing all that they can to keep the disease at bay.
A poultry scientist with the Alabama Cooperative Extension System said poultry producers are more vigilant than ever when it comes to sanitation and other biosecurity measures.
“All our Alabama poultry growers have biosecurity measures in place,” said Ken Macklin. “Biosecurity measures are the first line of defense against avian influenza and other poultry diseases.”
Macklin said that more than 43 million chickens and turkeys have either died from the disease or had to be euthanized because the flock tested positive for a highly contagious form of avian influenza in the first five months of 2015. The most severely impacted states are in the upper Midwest, including Iowa, Minnesota, South Dakota and Wisconsin.
“These cases in commercial poultry operations in the upper Midwest have mostly been linked to a failure of biosecurity,” said Macklin. “Growers may have thought they were following biosecurity guidelines fully, but it seems that there were lapses.”
Macklin, who is also an associate professor of poultry science at Auburn University, said strong biosecurity measures take many forms, including:
- Isolating the birds from other animals
- Minimizing access to people and unsanitized equipment
- Keeping the area around the poultry buildings clean and uninviting to wild birds
- Sanitizing the facility between flocks
- Cleaning equipment entering and leaving the farm
- Having an all in, all out policy regarding the placement and removal of the birds
- Disposing properly of bedding material and any mortalities
Joseph Giambrone, an Auburn University professor of poultry science, called the losses to the national poultry industry staggering.
“The losses are in the hundreds of millions of dollars,” said Giambrone. “We can expect a reduction of at least 10 percent in egg laying production and a similar drop in turkey production nationally.”
Macklin said the potential production loss is why Alabama producers are working hard to keep their flocks free of the disease. According to Auburn University research done in 2012, poultry and egg production and processing contributed more than $15 billion to the state’s economy and employed more than 86,000 people.
Giambrone, whose research focuses on viral diseases of poultry, said the disease is spread by migrating water fowl such as ducks and geese.
“This outbreak began in Canada, and water fowl spread it south along the migratory bird flyways,” he said. “It was brought into the Midwest by birds using the Mississippi flyway. It has persisted so long there because of the heavy concentration of poultry producers in that region of the country.”
Giambrone said ducks and geese shed the virus in fecal material.
“Infected water fowl shed the virus into ponds and lakes as well as onto the land they are grazing.”
Macklin said that warmer weather may slow the disease’s spread.
“The virus can survive for days, especially if it is in water. In water, the virus can survive up to 100 days with a water temperature of 63 degrees Fahrenheit. But when water temperatures reach the 80s, the virus can survive for less than a month.”
He said the virus has a reduced ability to survive on land.
“On land, the virus can survive for 30 days at 40 degrees Fahrenheit and 7 days at 68 degrees Fahrenheit,” said Macklin. “Once the outside temperature hits the 80s the virus breaks down in hours.”
While warmer weather may halt the disease’s progress in the United States, Giambrone emphasized that the disease can return next year.
“Even if we get control of the disease this year, wild water fowl in Alaska and Canada remain carriers of the disease and are a threat to bring it back to the United States when they migrate again next year.
By Maggie Lawrence
Avian Influenza Outbreak in the U. S.: Auburn University Professor Answers Frequently Asked Questions
Avian Influenza has gained the public attention again as the U.S. deals with a widespread outbreak in the upper Midwest of the “Highly Pathogenic (HPAI) H5” form of the disease. Avian Influenza is a viral disease of birds, more specifically one caused by a Type A Orthomyxovirus, which has also infected other species, including birds, pigs, horses, seals, whales, and humans. The size of the current outbreak is quite large and unfortunately spreading into areas where commercial poultry (chickens and turkeys) are grown. The first case was identified in a backyard flock in Oregon on December 19, 2014. The disease then rapidly spread to Washington, eventually moving into turkey flocks in Minnesota and chickens in Iowa. As of 23 April, almost 7.5 million birds have been destroyed in an attempt to get ahead of the outbreak, with the hope of preventing it from spreading into the southeast U.S., where very large numbers of commercial poultry are produced.
Up-to-date details on the ongoing outbreak are available from USDA-APHIS.
Where did the disease come from? The general scientific consensus is that the virus originated in free ranging waterfowl, where the virus easily circulates without causing overt disease or large scale mortality. Waterfowl carrying the H5N8 form of the virus are thought to most likely have picked up the virus during migration out of Asia, carrying it into the Pacific flyway and eventually eastwardly into the upper Midwest. Other forms of the virus may also have been present, some mutating so that they became very pathogenic (i.e. deadly) to poultry. The U.S. Department of Agriculture (USDA) has subsequently identified other forms of the virus, including H5N2 and H5N1. Some strains of H5N1 Avian Influenza Viruses have caused human sickness and mortality in Asia. It is important to note that the strains of the virus found in North American waterfowl are not the same as those causing human illness and mortality in Asia. In fact, the Centers for Disease Control (CDC) has concluded that the human risk from the North American waterfowl viruses is very low. To date, the outbreak has been associated with the Pacific, Mississippi, and Central flyways, where weather conditions were cool and wet, so the disease was able to migrate out of ducks and geese and into hobbyist and eventually commercial poultry flocks. Many scientists feel that the spread of the disease will slow as weather conditions change to warmer, dryer air. This change, however, will not eliminate the virus in waterfowl populations, where it will continue to circulate and potentially cross once again into commercial poultry when fall and winter conditions return. If this scenario plays out as many scientists expect it will, the disease will become endemic (if it is not already) to the North American continent, likely resulting in an eventual adoption of a federal preventative vaccination approach.
What is the government doing to prevent the spread of the disease? The USDA is aggressively moving to contain the disease. Commercial poultry flocks are being monitored by both state and federal scientists and if identified as infected, these flocks are quickly euthanized and buried in approved sites. To date, the USDA has chosen not to vaccinate nearby flocks (a process called “ring vaccination”) because of the potential effect this might have on international trade and the unavailability of the vaccine in quantities necessary for the scope of the current outbreak. The USDA is, however, currently working on the development of a vaccine, and many expect that they will eventually allow its use if the disease continues to spread.
The USDA’s current approach to dealing with the problem occurs in five stages (see this link: www.aphis.gov/wps):
- Quarantine – restricting movement of poultry and poultry-moving equipment into and out of the control area
- Eradicate – humanely euthanizing the affected flock(s)
- Monitor region – testing wild and domestic birds in a broad area around the quarantine area
- Disinfect – killing the virus in the affected flock locations
- Test – confirming that the poultry farm is Avian Influenza virus-free.
Can I, or my family, be infected by Avian Influenza? Infection can occur with the virus, but it is highly unlikely because of the current genetic makeup of the virus. There does not appear at this time to be any significant risk in the U.S. of a widespread or epidemic outbreak of Avian Influenza in humans. This opinion is based on current epidemiological data, medical and veterinary diagnostic availability in the U.S., and societal norms and practices, which limit virus spread. The American public is widely separated from commercial food production and unlike Asia, where human disease has occurred, generally does not buy poultry from live markets (in such markets, inspection may not be as stringent as in commercial agriculture). Avian Influenza deaths have occurred in Asia and other places around the world, but these instances were unique and often the result of long-term exposure or consumption of sick or dead birds. The viruses found in the current U.S. poultry outbreak are not the same viruses that caused human sickness and death in Asia. The U.S. food supply is the safest in the world. Sick birds infected with Avian Influenza do not enter the food chain in the U.S. because of the very vigorous monitoring and inspection process, cooperatively led by the commercial poultry production companies as well as state and federal authorities. Full monetary compensation for infected flocks by the federal government, which is often not available in other countries, also encourages reporting, lessening the risk even further.
Is the USDA working with other agencies to ensure the disease does not cross into humans? Yes. The USDA-led efforts to contain and eradicate HPAI is part of a larger program that includes cooperative efforts with the CDC. The concept behind this and other joint animal health efforts is called “One Health.” The One Health program recognizes that the health of animals, people, and the environments in which they live are intricately linked. The USDA is working to contain and eradicate the disease in poultry. The agency also works with the CDC to ensure the disease has not jumped from the avian species to humans.
A detailed description of the One Health program is available from USDA-Veterinary Services and the CDC.
Additional information on Avian Influenza is available from the CDC.
Does USDA work with state agencies to monitor animal diseases like Avian Influenza? Yes. Animal health surveillance is a cooperative effort of federal, state, and agribusiness animal health professionals. The USDA has established the National Animal Health Surveillance System (NAHSS) to integrate animal health monitoring and surveillance at the state and federal level, creating a comprehensive and coordinated system.
Details of the NAHSS program are available from USDA.
The USDA also coordinates another program called the National Animal Health Monitoring System (NAHMS), which conducts national studies on the health and health management of U.S. domestic livestock and poultry populations.
Details of the NAHMS program are available from USDA.
The USDA has also created the National Animal Health Laboratory Network (NAHLN), which includes state animal health laboratories. When a large-scale animal outbreak occurs, like the current HPAI outbreak, tracking and diagnosis can severely overtax federal laboratory capacity. The collaborative state-level NAHLN then becomes an important partner in response. At the Federal level, the USDA’s National Veterinary Services Laboratory (NVSL) coordinates diagnostic efforts and serves as the reference and confirmatory laboratory. State and University veterinary diagnostic laboratories that are members of the NAHLN network perform routine diagnostic tests and targeted surveillance testing, including that which is occurring in this outbreak.
Details of the NAHLN are available from USDA-APHIS.
Are poultry products (meat and eggs) safe to consume? Yes! It bears repeating. The U.S. food supply is the safest and most abundant in the world. Poultry meat and eggs are inspected and never put into the food chain if originating from flocks infected with HPAI. Even so, like all raw meat products, due diligence in the kitchen should always be practiced to ensure safe handling and storage. Poultry meat and eggs are perishable products that can be cross-contaminated with bacteria or viruses, causing food safety problems. Poultry products should always be thoroughly cooked and never consumed raw—not because of the potential presence of the Avian Influenza virus but instead because other potential food-borne pathogens may be present.
Additional information on food safety practices is available at: http://www.fsis.usda.gov/wps/portal/fsis/topics/food-safety-education/get-answers/food-safety-fact-sheets
Is there anything I should do if I am a poultry hobbyist to protect my flock against Avian Influenza? Yes. Practicing effective biosecurity is essential when dealing with hobby poultry flocks. Hobby flocks should not be allowed to comingle with wild birds or waterfowl or range in areas where these may be present. Water supplies should also not come from lakes or ponds where waterfowl are present. Wild birds should also be excluded from pens or feeding areas. When handling birds, the USDA recommends the following:
Do not pick up deceased or obviously sick birds. Contact your state, tribal, or federal natural resources agency if you find sick or dead birds. Other safe practices include: (Link: http://www.aphis.usda.gov/animal_health/birdbiosecurity/biosecurity/wildbirds.htm)
- Wear rubber gloves when cleaning your bird feeders
- Wash hands with soap and water immediately after cleaning feeders
- Do not eat, drink, or smoke while cleaning bird feeders
What does a sick bird with Avian Influenza look like? The signs for sick birds can be very subtle or quite distinct depending on the type of Avian Influenza virus involved and the stage of the disease. The USDA lists the following signs, which may be singly present or in combination: (Link:http://www.aphis.usda.gov/animal_health/birdbiosecurity/AI/)
- Sudden death without other clinical signs
- Lack of energy and appetite
- Decreased egg production; soft-shelled or misshapen eggs
- Swelling of the head, eyelids, comb, wattles, and hocks
- Purple discoloration of the wattles, combs, and legs
- Nasal discharge
- Coughing and/or sneezing
- Lack of coordination
Domestic turkeys infected by HPAI may show similar signs to chickens, shown here, including swollen head and eyelids.
Training materials for recognizing Avian Influenza Symptoms is available from USDA-FSIS Link: http://www.fsis..gov/wps/portal/fsis/topics/inspection/workforce-training/regional-on-site-training/avian-influenza-training
Additional downloadable biosecurity resources for the poultry hobbyist are available from the following USDA Websites.
Instructions for obtaining hard copies of the materials are available at: http://www.aphis.usda.gov/publications/how_to_order_publications.pdf
Do pet bird owners need to practice similar biosecurity measures? Yes. Avian influenza has on occasion infected other avian species beyond ducks, geese, and turkeys. Birds are very popular pets and sometimes originate in other parts of the world that may be experiencing HPAI outbreaks. Unfortunately, many of the most exotic birds are highly prized, often endangered, and therefore very expensive and frequently smuggled. The USDA quarantines and tests live birds legally imported into the U.S. Exotic bird owners should not patronize bird smuggling operations—not only because it is a federal offense but also because it endangers the very birds they may already possess. USDA recommends the following standards of practice: (Link: http://www.aphis.usda.gov/animal_health/birdbiosecurity/biosecurity/petbirds.htm)
- When buying a pet bird, request certification from the seller that the birds was legally imported or came from U.S. stock and was healthy prior to shipment.
- It is a good idea to have your new bird examined by a veterinarian.
- Isolate new birds from your other birds for at least 30 days.
- Restrict access to your birds, especially from people who own birds that are housed outside.
- Keep your birds away from other birds.
- Clean and disinfect your clothing and shoes if you have been near other birds, such as at a bird club meeting or bird fair or at a venue with live poultry.
- Wash your hands thoroughly with soap, water, and disinfectant before and after handling your birds.
- Keep cages, food, and water clean on a daily basis.
- Remove feed from bags; place it in clean, sealed containers; and throw bags away.
- Do not borrow or share bird supplies. If you must, clean and disinfect the items before bringing them home.
Is there anything that hunters should do to protect themselves and their families? Again, yes. Diligent biosecurity is essential. If practiced effectively, it costs very little. Commercial poultry farmers should refrain from waterfowl or turkey hunting since the risk of carrying back the virus is too great. Many commercial poultry companies actually contractually prohibit their growers from conducting practices outside a set of very strict guidelines, including hunting waterfowl. It obviously is in the best interest of the growers to adhere to the guidelines since compensation for infected flocks comes to the owner of the flocks (In the U.S., these owners are generally the poultry production companies) and not the grower. The USDA recommends the following:
Follow routine precautions when handling wild birds.
- Do not handle or consume game animals that are obviously sick or found dead.
- Do not eat, drink, or smoke while cleaning game.
- Wear rubber gloves when cleaning game.
- Wash hands with soap and water, or alcohol wipes, immediately after handling game.
- Wash tools and working surfaces with soap and water and then disinfect.
- Keep uncooked game in a separate container, away from cooked or ready-to-eat foods.
- Cook game meat thoroughly. Poultry should reach an internal temperature of 165 degrees Fahrenheit to kill disease organisms and parasites .
- To report unusual signs in birds you have seen in the wild, call 1-866-4-USDA-WS. To learn more about how you can help, visit usda.gov/birdflu.
A downloadable safe biosecurity practices wallet card for hunters is available at: http://www.aphis.usda.gov/animal_health/birdbiosecurity/downloads/USDA_HntrCd_Hi.pdf
Will the disease continue to spread and if so, what will be the effect on consumers? Prediction of how or where the disease might spread is difficult, if not impossible, at this time. Many scientists feel the problem will persist, but again that is an opinion, the accuracy of which has not yet been proven. Every step of containment and eradication, short of vaccination, is being conducted by poultry experts, including corporate, state, and federal officials. Exports of poultry meat, eggs, and egg products from the areas associated with the current outbreaks have been negatively affected. A substantial number of poultry have also been eradicated, causing regional decreases in supplies. Combined, these two, in some ways competing, elements have yet to cause any substantial increase in overall U.S. poultry prices. This trending or neutral effect on U.S. poultry prices is likely not to be maintained, should the outbreak continue to spread in the upper Midwest and euthanized bird numbers increase dramatically. If the disease spreads to the Southeast, the consumer economic effect is likely to remain unavoidable, and prices of poultry meat and eggs will probably increase, perhaps dramatically. However, the situation will remain complex and largely dependent on the consumer response. Some consumers will likely turn from poultry consumption either from unwarranted fear or from price increases that may occur. Such responses ease pressures on prices and with time can cause price increases to moderate.It is important to note, however, that the medium to long-term economic effect predictions are made more difficult to predict because Avian Influenza is occurring in other countries around the world, in some places even becoming endemic (meaning persistent in the local bird population). These countries might export to the U.S. as substitute suppliers. If this worldwide trend continues, the overall availability of poultry meat, eggs, and egg products will likely decrease, thereby causing an overall increase in poultry prices.
If HPAI crosses the continent and enters into the Southeast commercial poultry flock, as some speculate it will in the fall of this year when cool moist weather returns, the economic effect could be severe and prolonged, particularly if breeder flocks (the birds that provide the eggs that become the broilers we consume and the layers, which give us the eggs we eat) become sick from the virus. Should the breeder flock be affected on anything approaching a large scale, we are looking at a potentially unprecedented negative economic effect to the U.S. economy. American citizens expect a readily available and economical food supply. If HPAI continues to spread at the current rate or is proven endemic on the North American continent, implementation of additional strategies, including vaccination, are highly likely. The alternative, at least for poultry and poultry products, is to surrender the assurance that ready availability at reasonable prices is be possible.