Swine Influenza: Symptoms, Diagnosis, and Control

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What are the clinical signs of swine influenza in pigs?

Depression, mucous nasal discharge, and sneezing (correct)

Sneezing, fever, and coughing

Anorexia, fever, and coughing

Lethargy, fever, and anorexia

How is influenza primarily diagnosed in pigs?

By PCR or virus isolation (correct)

By serological testing

By antibody testing

By viral culture

What role do pigs play in the overall epidemiology of influenza?

They are reservoirs for human seasonal influenza viruses

They contribute to the emergence of zoonotic strains with pandemic potential (correct)

They are not significant in the epidemiology of influenza

They act as carriers of avian influenza virus

What is the relationship between swine strains of IAV and human infections?

Human seasonal influenza viruses can establish in pigs Signup and view all the answers

What is the main antigenic protein responsible for viral attachment to cells and release of virions from infected cells?

Hemagglutinin Signup and view all the answers

Which family does the swine IAV belong to?

Orthomyxoviridae Signup and view all the answers

What is the primary factor that predisposes pigs to IAV infections?

Mixing of carrier or subclinically infected animals and susceptible pigs Signup and view all the answers

During which seasons are outbreaks of IAV in swine most common in North America?

"Fall or winter Signup and view all the answers

What is an important factor contributing to the endemic and widespread nature of IAV in pigs worldwide?

"Ongoing recruitment of susceptible hosts Signup and view all the answers

What is the primary mechanism for the spread of IAV within a herd?

"Movement of pigs between crates or pens Signup and view all the answers

What is the primary reservoir of influenza infection capable of spreading IAV to other farms after weaning?

"Herd's piglets prior to weaning Signup and view all the answers

What is the common factor associated with the introduction of IAV into previously uninfected herds and countries?

Carrier pigs Signup and view all the answers

What leads to recurrence of outbreaks of infection in antibody-positive herds?

As immunity wanes Signup and view all the answers

How does the spectrum of IAV infection typically range?

From subclinical to acute Signup and view all the answers

What causes bronchial epithelium necrosis and focal atelectasis in the classic acute form of IAV infection?

Hemagglutinin and neuraminidase proteins Signup and view all the answers

What is the main method for diagnosing influenza A virus (IAV) in nonvaccinated animals?

Virus isolation from nasal and oral secretions Signup and view all the answers

What is the main economic loss in many pig herds during an IAV outbreak?

Stunting and delay in reaching market weight Signup and view all the answers

What are the main signs of a classic acute outbreak of IAV in pigs?

Nasal and ocular mucous discharge Signup and view all the answers

What is the primary method for diagnosing IAV?

Direct viral isolation Signup and view all the answers

What are the characteristics of the lung lesions seen in uncomplicated IAV infections?

Clearly demarcated, collapsed, and purplish red areas with mucopurulent exudate Signup and view all the answers

What is the primary cause of losses in reproduction associated with IAV outbreaks?

High fever response Signup and view all the answers

What method may be needed to select epidemiologically relevant strains of IAV for evaluating virus-specific antibodies or custom vaccine production?

Sequencing and characterization of viral isolates Signup and view all the answers

What is the most common vaccination protocol used for prevention of IAV in pig herds?

"Sow vaccination" prefarrowing Signup and view all the answers

What is a characteristic feature of the thoracic cavity in uncomplicated IAV infections?

"Purplish red" affected areas Signup and view all the answers