POULTRY MED L2 - Avian Influenza

answer with TERM, FLASHCARD type, SHUFFLE

Avian Influenza

is a broad term used to describe any infection or disease in birds caused by Type A influenza viruses

Type A influenza viruses

Avian Influenza is a respiratory disease in poultry caused by ____

Orthomyxoviridae

Type A influenza viruses is from the family __________

Influenzavirus A

Type A influenza viruses is from the genus __________

Wild waterfowl and other aquatic birds

are the primordial reservoir of all influenza A viral gene

“Bird Flu”

is used as a simplified alternative to Avian Influenza by the media to describe infections in poultry, humans, and other mammals with Type A influenza viruses derived from birds

19th century

It has been recognized since the late ___ causing mainly sporadic, but serious disease outbreaks

Aquatic birds

are the natural hosts of type A influenza viruses, which are often migratory

Spillover

_____ of viruses from wild aquatic birds to poultry and other species occur frequently

1. 16 hemagglutinin (H1-H16)

2. 9 neuraminidase (N1-N9)

Type A influenza is classified into 2 subtypes

Hemagglutinins

Binds to the host cell receptors which initiates infections

Neuraminidase

Cleaves the bonds made by hemagglutinins and receptors

1. High Pathogenicity Influenza Virus (HPAI)

2. Low Pathogen Influenza Virus (LPAI)

2 strain types

1. H5

2. H7

2 HPAI strains

H1-H16

range of LPAI strains

HPAI Strains and LPAI Strains H5/H7

are of interest of the World Organization of Animal Health

LPAI Strains H5/H7

can mutate from LP to HP strains unpredictably

H5N1

High Pathogenicity Influenza Virus strain ___ is currently the most pathogenic strain of the Avian Influenza Virus

goose; Guangdong, China

H5N1 was first isolated from a ____ in ___, ___ in 1996, and in 1997, the first human cases were detected leading to 18 infections and 6 deaths

pandemic potential

The H5N1 strain poses a persistent threat with ____ due to their genetic recombination capacity, interspecies adaptability and high lethality

Pampanga and Nueva Ecija

The first reported cases of HPAI H5N1 in the Philippines occurred in 2021 in ___ and ___

Nueva Ecija

The first outbreak in the Philippines was confirmed in 2022, where the possible sources of infection were wild birds especially egrets, feed delivery trucks, and fresh duck eggs from ___

culling

The Poultry industry is at high risk of HPAI outbreaks, great economic loss is mainly due to ____

backyard

Greatest Impact of HPAI is on ___ poultry growers who raise only a few hundred layers for extra income

nares, mouth, conjunctiva, and cloaca

Avian influenza is shed from the ___, ___, ___, and ___ of infected birds into the environment

preen gland

HPAI viruses can also be detected in epidermis including feathers, feather follicles, and glands such as ____ resulting in environmental contamination

direct contact

The virus is transmitted by ____ between infected and susceptible birds

aerosol, droplets, fomites

The virus is transmitted by indirect contact through ___, ___, exposure to virus contaminated ____

oropharyngeal replication

Transmission through virus from the _____, because of the high virus concentrations, are likely through water contamination and direct contact

fomites

Large volume of lower concentration AI virus in infected feces makes ____ a major mode of transport

1. Other domestic and confined poultry

2. Migratory waterfowl and other wild birds

3. Domestic Pigs

4. Pet Birds

Potential sources of infection or initial introduction of the AI in commercial poultry include:

incubation periods

The ____ for the various diseases caused by these viruses range from as short as a few hours in intravenously inoculated birds to 3 days in naturally infected individual birds and up to 14 days in a flock

1. dose of virus,

2. the route of exposure,

3. the species exposed, and

4. the ability to detect clinical signs

The incubation period is dependent on the ___, the ___, the ___, and the ability to ___

host species, age, sex, concurrent infections, acquired immunity, and environmental factors

Clinical signs of disease are extremely variable and depend on other factors including ___, ___, ___, ___, ___, and ___

LPAI

which strain type has Respiratory Signs in domestic poultry (chickens and turkeys) that are coughing, sneezing, rales, rattles, excessive lacrimation

LPAI

which strain type has increased broodiness, decreased egg production in layers and breeders

LPAI

which strain type has Generali Clinical Signs: Huddling, Ruffled feathers, listlessness, decreased activity, lethargy, decreased feed and water consumption, occasionally diarrhea

Green diarrhea or green “urine”

LPAI 2 rare signs

no clinical signs

Most infections of LPAI in wild birds produce ___ ___ ___

H5Nx Gs/GD

lineage HPAI viruses which can infect and cause clinical disease including neurological signs, depression, anorexia, and sudden death

clinical signs

HPAI in domestic chickens, turkeys, and related galliformes, ____ reflect virus replication and damage to multiple visceral organs, and cardiovascular and nervous systems.

HPAI

which strain type has Clinical manifestations that vary depending on the extent of damage to specific organs and tissues (Not all clinical signs are present in every bird)

HPAI

in this strain type, in most cases in chickens and turkeys, the disease is fulminating with some birds being found dead prior to observation of any clinical signs

1. Tremors of the head and neck

2. Inability to stand

3. Torticollis

4. Opisthotonus

In HPAI, If the disease is less fulminating and birds survive for 3-7 days individual birds may exhibit nervous disorders such as:

HPAI

In this strain type, Poultry houses may be unusually quiet due to the decreased activity and reduction in normal vocalizations of the birds

Listlessness

is common as are significant declines in feed and water consumption in HPAI

Precipitous drops

___ in egg production occur in breeders and layers with typical declines including total cessation of egg production within 6 days in HPAI

HPAI

Respiratory signs of this strain type are less prominent than LPAI strains but can include: Rales, Sneezing, and Coughing

LPAI

which strain type have High morbidity and low mortality with Mortality is usually less than 5% unless accompanied by secondary pathogens or if the disease is in young birds

HPAI

which strain type have Morbidity and mortality rates that are both high wherein Mortality is around 50-89% and can reach up to 100% in some flocks. Typically, the virus spreads rapidly among poultry housed on the floor with peak mortality (70-100%) occurring withing 3-5 days. Spread of virus is slower in poultry housed in cages…

LPAI

In which strain type are these gross lesions: In gallinaceous poultry, the most frequent lesions are in the respiratory tract, especially sinuses, and are characterized as catarrhal, fibrinous, serofibrinous, mucopurulent, or fibrinopurulent inflammation

LPAI

In which strain type are these gross lesions: The tracheal mucosa can be edematous with congestion and occasionally hemorrhages. Tracheal exudates may vary from serous to caseous, with occasional occlusion of airways and resulting asphyxiation.

LPAI

In which strain type are these gross lesions: Fibrinous to fibrinopurulent air sacculitis may be present. The fibrinopurulent inflammation usually is accompanied by secondary bacterial infections.

LPAI

In which strain type are these gross lesions: The infraorbital sinuses may be swollen with muco‐to‐mucopurulent nasal discharge.

• Pasteurella multocida

• Escherichia coli

Fibrinopurulent bronchopneumonia in LPAI can result when accompanied by secondary pathogens such as ___ or ___

LPAI

In which strain type are these gross lesions: Catarrhal to fibrinous inflammation may be noted in the air sacs and coelomic cavity (“peritoneal cavity”), and “egg yolk peritonitis” may be observed

LPAI

In which strain type are these gross lesions: Catarrhal‐to fibrinous enteritis may be observed in the ceca and/or intestine, especially in turkeys.

HPAI

In which strain type are these gross lesions: In gallinaceous poultry, produce a variety of edematous, hemorrhagic, and necrotic lesions in visceral organs and the skin. Although, when death is peracute, no gross lesions may be observed.

HPAI

In which strain type are these gross lesions: In chickens, swelling of the head, face, upper neck, and feet may be observed which results from subcutaneous edema and may be accompanied by petechial‐to‐ecchymotic hemorrhages. Necrotic foci, hemorrhage, and cyanosis of the non‐feathered skin have been reported, especially wattles and combs.

HPAI

In which strain type are these gross lesions: Lesions in visceral organs vary with virus strain but most consistently are represented by hemorrhages on serosal or mucosal surfaces and foci of necrosis within parenchyma of visceral organs

HPAI

In which strain type are these gross lesions: Hemorrhages on the epicardium, pectoral muscles, and in mucosa of the proventriculus and ventriculus are very prominent

H5N1 Gs/GD

With the ___ lineage HPAI viruses, necrosis and hemorrhage in Peyer’s patches of the small intestine were common as was reported with outbreaks of fowl plague in the early 1900s

H5N1

___ strains tend to produce more severe hemorrhage and edema in the lung than other HPAI strains

HPAI

In which strain type are these gross lesions: With most of this viruses, necrotic foci are common in pancreas, spleen, and heart, and occasionally in liver and kidney.

urate deposits

In HPAI lessions, the kidney lesions may be accompanied by ___

HPAI

In which strain type are these gross lesions: Lungs have focal ventral-to-diffuse interstitial pneumonia with edema. The lungs can be congested or hemorrhagic. The cloacal bursa and thymus are usually atrophic.

tracheal, oropharyngeal, or cloacal

Sample Selection: Avian influenza viruses are commonly recovered from the ___, ___, or ___ swabs of either live or dead birds

1. Reverse transcriptase polymerase chain reaction (RT PCR)

2. Real‐time RT‐PCR (rRT-PCR)

3. Serology

3 diagnostics for AI

Real‐time RT‐PCR (rRT-PCR)

diagnostic used for field case diagnosis

Serology

used to demonstrate presence of AI specific antibodies which may be detected as early as 5 days after infection

1. Double immunodiffusion test

2. ELISA

2 serology diagnostics

HPAI

Differential diagnosics of what strain type:

1. Velogenic NCD

2. Septicemic fowl cholera

3. Heat Exhaustion

4. Water Deprivation

5. Toxins

LPAI

Differential diagnosics of what strain type:

1. Lentogenic NCD

2. Infectious Laryngotracheitis

3. Infectious Bronchitis

4. Chlamydia

5. Mycoplasma

1. Biosecurity

2. Active and Passive Surveillance

3. Elimination of infection in poultry

4. Decreasing host susceptibility

5. Education including risk communication

These goals can be met using a combination of five interrelated components

Active Surveillance

Involves regular sampling of domestic poultry and wild birds or the environment when no disease or symptoms is present

Passive Surveillance

Is a reactive case-based sampling where authorities investigate suspected cases based on reports from farmers, veterinarians, or the public, rather than actively searching for infections

HPAI

Elimination of Infection in Poultry on which strain type: this is accomplished by disposal of depopulation/stamping out and disposal of carcasses, eggs, and manure

LPAI

Elimination of Infection in Poultry on which strain type: Controlled slaughter or sell-down of birds after recovery from infection is an acceptable means of elimination. Eggs can be marketed if properly cleaned.

chickens and turkeys

Various Vaccine technologies have been developed and has been effective in experimental studies in __ and __ to provide protection from LPAI and HPAI viruses

Live recombinant

___ fowl poxvirus, herpesvirus of turkeys, and Newcastle disease vaccines with AI H5 gene inserts (rFPV‐AIV‐H5, rHVTAIV‐H5, and rNDV‐AIV‐H5, respectively) have been licensed and are used in a few countries

Volvac B.E.S.T AI plus ND

First AI vaccine in the Philippines. Approved by the FDA late August 2025.

commercial broilers

The vaccination is permitted for specific poultry types, including commercial layer chickens, breeders, ducks, and game fowls, but is generally restricted for ___.

Amantadine

has been shown experimentally to be effective in reducing mortality, but the drug is not approved for food animals, and its use rapidly gives rise to amantadine‐resistant viruses which compromises public health

broad-spectrum antibiotics

For LPAI infections, suppurative care and provision of __ __ for secondary infections may reduce mortality

True

T or F: No treatment currently viable for commercial poultry use