Initially revealed April 2022. Up to date by January 2025 to mirror additional developments within the outbreak.
Many individuals are involved concerning the outbreak of avian influenza, or chicken flu, that started in 2022 and has affected home poultry, waterfowl, raptors, shorebirds, different species of birds, and a few mammals in lots of elements of the world. As a result of the present pressure (H5N1) causes heavy losses to poultry, it’s known as extremely pathogenic avian influenza, or HPAI.
Transmission of avian influenza from birds to people is uncommon, based on Facilities for Illness Management. To this point, 14 individuals within the U.S. have examined optimistic for avian influenza. All had had contact with dairy cows or poultry farms, and all recovered. In June 2024, the World Well being Group reported a hospitalized man in Mexico had died from a unique pressure of avian influenza (H5N2), although the group deemed the chance to the overall inhabitants as low.
Experiences of Avian Flu in Birds
This explicit pressure of avian influenza virus impacts all kinds of untamed birds, together with hawks, eagles, falcons, owls, crows, vultures, shorebirds, recreation birds, seabirds, and particularly waterfowl akin to Canada Geese and Mallards (see checklist of species with HPAI detections, under). The virus is shed within the saliva, mucus, and feces of contaminated birds and is transmitted to different birds by way of ingestion or inhalation.
Due to the period of this outbreak, its latest unfold to mammal species, and widespread mortalities in some sorts of wild birds, there was concern about whether or not it’s protected for individuals to feed wild birds. In April 2022 and March 2023, we checked in with Dr. Julianna Lenoch, who directs the USDA APHIS Nationwide Wildlife Illness Program, and we’ve compiled the next summaries of key factors concerning HPAI, particularly amongst songbirds and different feeder guests. As of January 2025, there isn’t a official suggestion for individuals to take down chicken feeders due to the chance of avian influenza (see subsequent part). The Facilities for Illness Management has updates and proposals about H5N1 in people.
Low Danger of Avian Flu to Songbirds
There was widespread transmission of avian flu to wild chicken species together with waterfowl and raptors. The virus has additionally been present in mammals that prey on useless birds. Nevertheless, transmission to songbirds and different typical feeder guests has been low (about 3% of all circumstances reported in wild birds), though this may increasingly change with elevated testing or adjustments to the virus. Meaning there may be at present a low danger of an outbreak amongst wild songbirds, and no official suggestion to take down feeders until you additionally preserve home poultry, based on the Nationwide Wildlife Illness Program. We do at all times suggest that you simply clear chicken feeders and birdbaths frequently as a option to preserve many sorts of ailments at bay.
We additionally at all times suggest that you simply observe any suggestions put out by your state authorities, even in circumstances the place that recommendation conflicts with ours. The CDC’s web page on avian influenza in birds compiles further useful data and assets.
How do we all know songbirds are at low danger?
- USDA APHIS has a powerful, multiyear surveillance program that routinely samples wild birds, together with flocks of songbirds (and different species akin to Rock Pigeons and Mourning Doves which are typically round people), for the presence of avian influenza. Since January 2022 they’ve detected the HPAI pressure in 9,877 wild birds (plus 1,040 captive birds), with 304 detections in wild songbirds (see under for a listing of species). Newest data concerning the outbreak.
- Avian influenza doesn’t have an effect on all sorts of birds equally. The “extremely pathogenic” a part of the time period HPAI refers particularly to the severity of the illness in poultry, not essentially in different chicken species. For instance, waterfowl typically carry and transmit chicken flu, and with the present pressure they generally get sick or die. Raptors are far more delicate to the illness. Home poultry are extraordinarily vulnerable to HPAI and unfold the illness simply, resulting in as much as 100% mortality of affected flocks.
- Songbirds are a lot much less possible than waterfowl to contract avian influenza and fewer prone to shed giant quantities of virus, that means they don’t transmit the illness simply. (See Shriner and Root 2020 for an in depth evaluation within the journal Viruses.)
- In response to a separate research within the Journal of Wildlife Illnesses, “…though passerines and terrestrial wild birds could have a restricted function within the epidemiology of IAV [avian influenza A viruses] when related to contaminated home poultry or different aberrant hosts, there isn’t a proof supporting their involvement as pure reservoirs for IAV.” (Slusher et al. 2014)
- For these causes, it’s unlikely that chicken feeders will contribute to an outbreak amongst songbirds.
If songbirds are at low danger, why are individuals who preserve poultry suggested to take down their chicken feeders?
- The principle concern with songbirds is the prospect {that a} uncommon particular person may transmit an an infection to poultry. It is a concern as a result of poultry are a lot extra susceptible than songbirds to HPAI.
- The important thing intervention is to maintain songbirds away from poultry; it’s much less essential to maintain songbirds away from one another.
- If in case you have a yard poultry flock, these are crucial steps to take:
(click on for full data on these biosecurity measures from USDA APHIS) - As a secondary measure, USDA APHIS recommends for poultry house owners to take down wild chicken feeders or preserve them properly away from their captive flock
- For those who preserve chickens or geese, please see additionally newest data from the USDA Animal Plant and Well being Inspection Service.
For those who preserve nest bins:
Avian influenza is barely hardly ever transmitted to people, based on the USDA. The Facilities for Illness Management and Prevention considers most people well being danger from avian flu to be low. Nonetheless, our NestWatch undertaking at all times advises good hygiene and extremely recommends that folks put on disposable gloves and/or wash their fingers completely after checking nest bins. Most birds that use nest bins are songbirds, that are at low danger for contracting or transmitting avian influenza. For those who monitor waterfowl or raptor nests (e.g., Wooden Duck, Frequent Merganser, Canada Goose, American Kestrel, Barred Owl), we advise you put on gloves, change or wash gloves and disinfect gear between nest bins, put on a masks when cleansing out nest bins, and alter garments and footwear earlier than visiting any home poultry.
If you’re a wildlife rehabilitator:
Wildlife rehabilitators ought to take precautions when accepting sick birds in order that they don’t inadvertently introduce HPAI to the remainder of their sufferers. Right here’s additional steerage for rehabbers, from USDA APHIS. Rehabbers in New York State are additionally inspired to contact the Cornell Wildlife Well being Lab for extra data.
What to do for those who discover a sick or useless chicken:
Keep away from dealing with sick or useless birds. As an alternative, name your state wildlife well being company; they’ll decide reason behind loss of life and ship the chicken to the suitable lab for testing. Moreover, preserve pets (together with pet birds) away from sick or useless wild birds.
- Keep away from contact with birds that seem sick or have died
- Keep away from contact with surfaces which have chicken feces
- For those who should contact sick or useless birds:
- Put on gloves and a face masks
- Place useless birds in a double-bagged rubbish bag
- Throw away your gloves and facemask after use
- Wash your fingers properly with cleaning soap and heat water
Fowl flu will not be a danger to meals security. Poultry and eggs which are safely dealt with and cooked to an inside temperature of 165°F are suitable for eating.
For those who really feel sick after having contact with sick or useless birds, contact your well being care supplier.
Has Avian Flu Been Reported in Mammals?
There have additionally been reviews of mammals akin to pink foxes, skunks, bobcats, fishers, and bears contaminated with avian influenza, possible from consuming contaminated birds. Exterior the U.S. avian flu has contaminated farmed mink and has triggered losses at marine mammal colonies in South America. In March 2024 the USDA reported that avian flu has been present in cattle in a number of U.S. states. The CDC has further data on avian flu in cattle and related dangers to people.
Extra Assets:
Wild chicken species with HPAI detections in 2022–2024
Up to date January 3, 2025. Complete variety of detections in wild birds: 9,877 (plus 1,040 captive birds). Detections in passerines: 304. See Detections of Extremely Pathogenic Avian Influenza in Wild Birds for up to date detections.
Passerines (23 species)
American Crow (83 people, plus 13 unidentified crow spp.)
American Robin (2)
Barn Swallow (1)
Black-billed Magpie (15)
Boat-tailed Grackle (1)
Brewer’s Blackbird (2)
Frequent Grackle (4, plus 2 unidentified grackle spp.)
Frequent Raven (47)
Darkish-eyed Junco (1)
European Starling (16)
Fish Crow (7)
Grackle spp. (unidentified; 2)
Nice-tailed Grackle (6)
Home Sparrow (87)
Lark Bunting (1)
Lark Sparrow (1)
Purple-winged Blackbird (2, plus 2 unidentified blackbird spp.)
Savannah Sparrow (2)
Say’s Phoebe (1)
Tune Sparrow (4)
Summer season Tanager (1)
Tree Swallow (1)
Western Kingbird (1)
White-crowned Sparrow (1)
Non-Songbirds (145 species)
American Black Duck
American Coot
American Kestrel
American White Pelican
American Wigeon
Arctic Tern
Bald Eagle
Barn Owl
Barred Owl
Black Scoter
Black Skimmer
Black Turnstone
Black Vulture
Black-bellied Plover
Black-crowned Evening Heron
Black-legged Kittiwake
Blue-winged Teal
Bonaparte’s Gull
Brandt’s Cormorant
Brant
Broad-winged Hawk
Brown Pelican
Bufflehead
Cackling Goose
California Condor
California Gull
California Quail
Canada Goose
Canvasback
Caspian Tern
Cattle Egret
Cinnamon Teal
Frequent Eider
Frequent Goldeneye
Frequent Loon
Frequent Merganser
Frequent Murre
Frequent Tern
Cooper’s Hawk
Crested Caracara
Double-crested Cormorant
Dunlin
Eared Grebe
Japanese Screech-Owl
Eurasian Collared-Dove
Ferruginous Hawk
Forster’s Tern
Fulvous Whistling-Duck
Gadwall
Glaucous Gull
Glaucous-winged Gull
Shiny Ibis
Golden Eagle
Nice Black-backed Gull
Nice Blue Heron
Nice Egret
Nice Horned Owl
Higher Sage-Grouse
Higher Scaup
Higher White-fronted Goose
Inexperienced Heron
Inexperienced-winged Teal
Harris’s Hawk
Herring Gull
Hooded Merganser
Horned Grebe
Iceland Gull (Thayer’s)
Laughing Gull
Lesser Scaup
Lengthy-eared Owl
Lengthy-tailed Duck
Mallard
Merlin
Mottled Duck
Mourning Dove
Muscovy Duck
Mute Swan
Neotropic Cormorant
Northern Fulmar
Northern Gannet
Northern Harrier
Northern Pintail
Northern Shoveler
Osprey
Pacific Loon
Parasitic Jaeger
Peregrine Falcon
Pied-billed Grebe
Prairie Falcon
Razorbill
Purple-necked Grebe
Purple-necked Phalarope
Purple-shouldered Hawk
Purple-tailed Hawk
Redhead
Ring-billed Gull
Ring-necked Duck
Ring-necked Pheasant
Rock Pigeon
Roseate Spoonbill
Ross’s Goose
Tough-legged Hawk
Royal Tern
Ruddy Duck
Ruddy Turnstone
Ruffed Grouse
Sabine’s Gull
Sanderling
Sandhill Crane
Sandwich Tern
Sharp-shinned Hawk
Brief-billed Gull
Brief-eared Owl
Brief-tailed Shearwater
Snow Goose
Snowy Egret
Snowy Owl
Snowy Plover
Swainson’s Hawk
Trumpeter Swan
Tundra Swan
Turkey Vulture
Western Grebe
Western Gull
Western Sandpiper
Western Screech-Owl
White-faced Ibis
White-winged Dove
White-winged Scoter
Wild Turkey
Willet
Wooden Duck
Wooden Stork
