Lecture 18 Flashcards
What are the only diploid virus
Retroviruses
What is the problem with retroviruses
Mutate
How to retroviruses mutate
DNA copy of the genome is inserted into the DNA of the host cell that in invades, thus changing the genome of the cell
How do retroviruses cause persistent infections
The vision binds to the receptors on the cell surface via its envelope glycoproteins ‘spikes’. The viral reverse transcriptase uses the viral RNA genome as a template to make a DNA copy of the virus, a provirus. This provirus can become integrated into the DNA of the infected host cell
How are exogenous retrovirus transmitted
Horizontally
How are endogenous retrovirus transmitted
Are inherited vertically in the genomes of their host
How to retroviruses replicate
Must integrate a copy of it’s genome into the host’s genome as a provirus. If this occurs in a host germ cell, the provirus may be inherited by the host’s progeny and down the generations as an ERV
How did HIV first get into human blood
Practice of hunting and slaughtering bush meat
What is HIV-I closely related to
Simian immunodeficiency virus from chimps
What is HIV-2 closely related to
SIV from sooty mangabeys
What does feline immunodeficiency virus decrease
The function of the immune system of domestic and wild cats
What do cats with feline immunodeficiency virus has a higher chance of getting
Blood cancer
How is feline immunodeficiency virus spread
From cat to cat through saliva, primarily biting
How many clades of feline immunodeficiency virus are recognised
A-F and U (New Zealand)
Can you treat feline immunodeficiency virus
No
Preventing the spread of feline immunodeficiency virus
Spay or neuter
Keep indoors
How do diagnose feline immunodeficiency virus (3)
- Detection of provirus DNA by PCR
- Detection of viral RNA by RT-PCR
- Detection of antibody by ELSIA or immunochromatography
What is the single biggest cause of clinical signs of feline leukaemia virus
Immunosupression
Once the cat is infected with feline leukaemia virus A what can happen
Virus mutates
What does FeLV-B increase
Frequency of neoplastic diseases
What is FeLV-C strongly associated with
Development of erythroid hypoplasia and consequent severe anaemia
What does FeLV-T have propensity to infect and destroy
T lymphocytes, leading to lymphoid depletion and immunodeficiency
How is feline leukaemia virus transmitted
Oronasal contact with infectious saliva or urine
Where does feline leukaemia virus replicate
Oropharyngeal lymphoid tissue
Does feline leukaemia virus have treatment
No
How to prevent feline leukaemia virus
Unstable in environment and is susceptible to all common detergents and disinfectants
Is feline foamy virus pathogenic
No
How is equine infectious anaemia virus transmitted
Blood by blood-feeding tabanid flies between horses in close proximity
What are the clinical signs of infectious anaemia virus
- Fever, depression and thrombocytopenia
2. Anemia, petechiation of mucous membranes, dependent oedema, muscle weakness and loss of condition
What is the pathology of infectious anaemia virus
Gross lesions frequently seen in acute cases.
Enlargement of the spleen, liver and abdominal lymphnodes; dependent oedema and mucosal haemorrhages
How to clinically diagnose infectious anaemia virus
Demonstration of antibodies to the virus in blood
What does small ruminant lentivirus infect
Sheep of goats with these viruses cause slow, progressive, inflammatory pathology in many tissues
Where are the most common clinical signs in pathology of small ruminant lentivirus
Lung, mammary gland, CNS and joints
How is small ruminant lentivirus transmitted
To young through milk or colostrum
What does Maedi-Visna cause
Dyspnea and wasting
Causes ill-thrift, chronic respiratory disease and indurative mastitis
What is the pathology of Maedi-Visna
Sheep with maedi
- Lungs enlarged, abnormally firm and heavy and fail to collapse when thoracic cavity is opened
- Typically emphysematous and mottled or uniformly discoloured
In sheep with Visna
- May be focal, asymmetric, brownish point areas in the white matter of the brain and spinal cord
Describe caprine arthritis-encephalitis virus polyarthritis
Chronic, painful poly arthritis, accompanied by synovitis and bursitis is the main syndrome in adult goats infected
Describe caprine arthritis-encephalitis virus encephalomyelitis
Seen in kids (2-4 months), exhibits weakness, ataxia and hindlimb placing deficits. Over time causes paralysis
What are the clinical signs of Jaagsiekte sheep retrovirus
Tumors become sufficiently large or numerous enough to interfere with respiration
Where does Jaagsiekte sheep retrovirus replicate
Lung tumor cells, released into airways and is found in respiratory secretions
What is persistent lymphocytosis of bovine leukaemia virus considered
Benign condition associated with BVL infection
What are the clinical sings of lymphosarcoma in bovine leukaemia virus
Juvenile: sudden onset of diffuse lymphoid hyperplasia with to without visceral organ involvement
What type of disease does Jembrana disease virus cause
Acute disease
