EPI MT 2 DECK 1 Flashcards
(46 cards)
African Swine Fever virus family?
Asfarviridae, Asfivirus
Vectors of ASF?
Biological vectors, can replicate in all stages of life. Present in Ornithodorus
ASF resistance?
HIGH. Can survive in the environment for 100-200 days. Years long in freezer. 3-7 months in the soil.
Pathogenesis of African Swine Fever?
- Infection Per os or tick bite.
- Shedding in saliva , nasal discharge 48hrs before clinical symptoms.
- Primary replication in tonsils, lymph nodes.
- Viraemia for months
- Replication in monocytes, macrophages, hepatocytes, tubular epithelial, granulocytes.
- NOT lymphocytes
- Virus releases proteins causing immunosuppression.
Clinical Signs of African Swine Fever?
- Fever, transient anorexia, abortion on ALL variants.
- Haemorrhages on the skin with necrotic areas and nasal discharges.
Pathology of African Swine Fever?
- Acute: Petechial Haemorrhages, Pulmonary Oedema
- Chronic: Spleen, Lymphoid Hyperplasia, Fibrin fluid rich. Chronic in wild boar.
- LOW virulence: Multifocal skin necrosis, swelling of carpal and tarsal joints.
- Blood and Haemorrhages everywhere. Black, bloody lymph nodes.
Teschovirus Encephalomyelitis Virus genera?
Picornaviridae
Properties of Teschovirus Encephalomyelitis?
- Non-enveloped, +ssRNA
- PH 3-9
- 13 different serotypes
African Swine Fever properties?
- Linear dsDNA
- 1 Serotype, Many Genotypes
- Virulence variants High.
Teschovirus Epidemiology?
- Only Pigs are susceptible
- Teschen: all group ages
- Talfan: Below 4 months of age
- Spreading with faeces for 7-8 weeks
- Resistant in for 3 weeks
Teschovirus Pathogenesis?
- Infection PO, nose, olfactory nerves–> CNS
1. ) Enteral Phase: GI epithelium –> Primary replication in lymphoid tissue. Asymptomatic infection frequent.
2. )Viraemia: Depression, anorexia
3. ) Neural Phase: Secondary replication. Encephalomyelitis.
Teschen clincal signs?
- Incubation 1-3weeks.
- Mild fever, anorexia
- Piglet, grower phase–> Vomiting, ataxia, convulsions, flaccid paralysis, respiratory, paralysis, Hyperaesthesia.
- Flaccid Paralysis of HL.
Talfan clinical signs?
- Piglets below 4 months of age.
- Ataxia, paralysis of HL
- Recover, ataxia can remain
Swine Vesicular Disease Properties?
- Enterovirus
- One Serotype
- Good resistance ( faeces, meat)
Swine Vesicular Disease Epidemiolgy?
- Spreading: direct contact( discharges, faeces)
- Shedding the virus: lasts for 4 months.
- Asymptomatic carriers also shed.
- Indirect infection- Human can transmit.
Swine Vesicular Disease Pathogenesis?
- Infection PO–> Throat, gut. Epitheliotrop.
- Viraemia : Epithelial cells of mouth, snouts, teats, legs: vesicles.
- CNS: Rare or Asymptomatic.
SVD Clinical signs?
o Incubation time: 2-7 days o Fever: 1-2 days (41oC) o Vesicles: nose (snout), oral MM, legs (damaged horn production), vesicles will be ruptured w/in 1-2 days o Lack of appetite, limping o Fast recovery o Frequently asymptomatic
SVD caused by Senecavirus?
- Clinical signs: Suckling piglets general Fever, depression, Diarrhea. Growers, fatteners: Vesicles on the legs.
- PATHO: Piglet Inflammation of the oral mucosa, interstitial pneumonia, encephalitis. Adults do not die.
Vesicular Exanthema of Swine cause?
Caliciviridae, Vesivirus
Vesicular Exanthema Patho n Clinical signs?
- EPI: primary infection–> raw meat of sea mammals.
- Shedding: with saliva and excretions
- Survives for at least 2 weeks in the environment. Good resistance.
- Less contagious than FMD, doesn’t replicate as fast.
- CLINICAL SIGNS: 1-4 days of incubation. Skin lesions, anorexia, fever, depression, vesicles, lameness due to vesicles on the feet
Avian Encephalomyelitis Virus? Properties?
- Tremovirus
- High Resistance
- One Serotype
- Good Antigen, Widespread seropositivity–> Clinical signs rare.
Avian Encephalomyelitis Epidemiology?
- Chicken and Pheasant are susceptible.
- All age groups are susceptible.
- Maternal protection 3-6weeks.
- Clinical signs: 1-2weeks up to 4-5weeks old.
- Spread: germinative–>infected eggs for 3weeks, faeces.
- Morbidity: 50-60%, Lethality high.
Avian Encephalomyelitis Pathogenesis?
- Per os, mucous membrane of the gut.
- Viraemia–> Pancreas, Liver, kidney, ovarium( does not kill embryo).
- CNS: inflammation, necrosis.
- Good immunity, maternal protection
Avian Encephalomyelitis Clinical Signs?
- Incubation 1-11 days
- Nervous signs: ataxia, tremor, paralysis
- Older animals: subclinical
- Egg production drops