Respiratory & CNS Diseases in Swine

Question 1

What viral family causes swine influenza?

Answer 1

Orthomyxoviridae

Question 2

Is Orthomyxoviridae RNA or DNA? Naked or Enveloped?

Answer 2

RNA segmented and enveloped

*Reassortment occurs frequently!

Question 3

Is swine influenza zoonotic?

Answer 3

Some strains are
(H1N1)
Swine can be infected with H3N2 from humans or birds (Inapparent infections)

Question 4

What ‘segments’ did swine flu have?

Answer 4

People, poultry and pig

H1N1

Question 5

Why are pigs such a concern with swine flu?

Answer 5

They can get a avian or human version, and genetic re-assortment can occur creating new strains
Pig –> human transmitted easily

Question 6

In what swine disease are antigenic shifts a huge concern?

Answer 6

Swine flu

Can be a huge outbreak or a small population could be infected

Question 7

Do people die from swine flu alone??

Answer 7

Typically people die from secondary infections, like pneumonia

Question 8

What was scary about the 2009 H1N1?

Answer 8

It was not very young/old dying. It was young healthy adults, especially pregnant women
(Triple reassortment)

Question 9

What disease in swine is known for having many animals infected at the same time (explosive outbreak)?

Answer 9

Swine flu

Question 10

What are the clinical signs of swine flu?

Answer 10

Fever, apathy, anorexia, respiratory disease, coughing, rhinitis, labored breathing and bronchial rales at auscultation

Question 11

How fatal is swine flu in pigs?

Answer 11

Less than 1% mortality, in uncomplicated cases

Animals could die from severe bronchopneumonia

Question 12

What are the economic consequences of swine flu?

Answer 12

Pigs do not grow, they lose weight

Question 13

You necropsy a pig and see sharply demarcated lesions in lung, hyperemia, consolidation and exudate in the airways. What disease should you be concerned with?

Answer 13

Swine flu

Question 14

What is seen histologically in the lungs in swine flu?

Answer 14

**Alveolar atelectasis, interstitial pneumonia and emphesyma

Question 15

How do you diagnose swine flu?

Answer 15

Chick embryo and cell culture for viral isolation in reference labs
Isolate can be identified by IF or enzyme-immunoassays using Mabs specific for the type/subtype

Question 16

Are there vaccines for swine flu?

Answer 16

Yes, they are not widely used

Not very effective due to different strains

Question 17

What viral family causes Porcine Reproductive Respiratory Syndrome (PRRS)?

Answer 17

Arteriviridae

Question 18

Is Arteriviridae RNA or DNA? Enveloped or naked?

Answer 18

RNA, enveloped

Question 19

Does Porcine Repro Resp Syndrome virus persist in the environment?

Answer 19

Yes, at low temperatures

even though it is enveloped

Question 20

Can Porcine Repro Resp Syndrome virus cause abortion?

Answer 20

Yes

Question 21

How is Porcine Repro Resp Syndrome transmitted?

Answer 21

Contact, airborne and sexual transmission via semen

Question 22

Who is Porcine Repro Resp Syndrome maintained in?

Answer 22

Persistently infected healthy swine (isolated from oropharynx 5 months after recovery)

Question 23

In what swine virus does quick spread occur in a naive population with 95% of animals serocoverting within a couple months?

Answer 23

Porcine Repro Resp Syndrome

Question 24

What are the clinical signs of Porcine Repro Resp Syndrome, besides anorexia and fever?

Answer 24

Blue discoloration of the ears, snout and vulva, agalactia and abortion in late gestation (day 110)

Question 25

You arrive at a pig farm and notice that several of the pigs have discoloration of the ears, snout and vulva. Some of the females are not producing milk while others have aborted late in gestation. What disease do you suspect?

Answer 25

Porcine Repro Resp Syndrome (Arteriviridae)

Question 26

How does Porcine Repro and Resp Syndrome affect reproduction?

Answer 26

Premature, still births and mummified fetuses are possible

Born alive piglets are weak and will die within a week due to respiratory distress

Question 27

What sample must be sent to the lab to determine if a group of pigs is infected with Porcine Repro Resp Syndrome?

Answer 27

Moribund live pigs (used for virus isolation, virus is quickly inactivated in aborted fetuses)

Question 28

What cells commonly used in labs does Porcine Repro Resp Syndrome replicate in?

Answer 28

Swine lung macrophages and monkey cell kidney line

Question 29

What control is used for Porcine Repro Resp Syndrome?

Answer 29

Attenuated vaccines are available, but rarely used