Final Exam - Picornaviridae Flashcards Preview

Virology > Final Exam - Picornaviridae > Flashcards

Flashcards in Final Exam - Picornaviridae Deck (19):
1

Two important genera of Picornaviridae

Aphtovirus and Enterovirus

2

Picornaviridae Replication

Poliovirus does not enter cells through endocytosis.

3

Enterovirus

Cause of Swine Vesicular Disease and Polioencephalomyelitis.

4

Swine Vesicular Disease Virus (SVDV)

Enzootic in Italy. Resistant to ambient temperature and to sodium carbonate. Transmitted in pork products. Not found in NA/USA and is an FAD.

5

SVDV Transmission

Virus infects swine via skin abrasions and mucosa by ingestion and inhalation. Direct contact among infected swine or with their excretions.

6

SVDV Clinical Features

Sudden appearance of lameness. Vesicles appear at the junction between the heel and coronary band. Lesions on snout, lips and tongue. Some develop encephalomyelitis.

7

SVDV Pathogenesis

Infection through fecal-oral route. Replication is in the GIT. Skin abrasion may act as portals of entry. Particularly feet. Viremic within 24 h.

8

SVDV Diagnosis

Case should be treated as FMD. RT-PCR multiplexed assays which can detect multiple agents at once. ELISA if vesicular fluid is collected. Virus isolation in swine kidney cells.

9

SVDV Vaccine

THERE IS NO VACCINE!

10

Foot and Mouth Disease Virus (FMDV)

Picornaviridae, Aphthovirus. Not cross protective. A disease of cloven hoofed animals.

11

FMDV Clinical Signs

Fever, excess salivation, nasal discharge (cattle). Initially vesicles on buccal areas, coronary bands and interdigital space. Recover in two weeks unless secondary infections arise.

12

FMDV Clinical Signs in Sheep and Goats

Mild, if any, signs.

13

Why care about FMD?

Highly contagious. Loss of livestock production cause economic loss. Limitation of international trade in livestock and animal products.

14

FMDV Transmission

Respiratory aerosols, direct contact and indirect contact via fomites.

Sheep = maintenance host and carrier for 4-6 mo.
Pigs = amplifier host and is not a carrier
Cattle = indicator host and is a carrier for 6-24 mo.

15

FMDV Diagnosis

Virus isolation and identification (vesicular fluid). Antigen or nucleic acid detection. Complement fixation, ELISA and virus neutralization.

16

FMDV Sample Collecting for Testing

Authorities should be contacted before collecting. Notify authorities and wait for instructions before collecting samples. Sample-s are sent under secure conditions and to authorized laboratories.

17

FMDV Treatment

There is no treatment available. Outbreak results in quarantine, euthanization, and disposal. Vaccines are available.

18

FMDV Disinfection

Effective solutions include: 2% sodium hydroxide (lye). 4% sodium carbonate (soda ash), 5.25% sodium hypochlorite (household bleach), 0.2 citric acid. Areas must be free of organic matter.

19

FMDV - Vaccination

Killed vaccine, serotype specific. Used to control outbreak. Will have to have annual revaccination. Does not protect against infection with other serotypes.