Lecture 6 - Part. 2 RPV, CBPP & LSDV Flashcards
Rinderpest is also known as
cattle plague
rinderpest is caused by
a virus called Rinderpest virus (RPV).
this is a morbillivirus (family paramyxoviridae).
RINDERPEST (RP) is
an acute, highly contagious disease of cloven-hooved animals, caused by Morbillivirus, characterized by fever, necrotic stomatitis, gastroenteritis, lymphoid necrosis, and high mortality.
RINDERPEST (RP) is an acute, highly contagious disease of cloven-hovfed animals, caused by
Morbillivirus.
RINDERPEST (RP) is an acute, highly contagious disease of cloven-hooved animals, caused by Morbillivirus, characterized by (5)
fever, necrotic stomatitis, gastroenteritis, lymphoid necrosis, and high mortality.
Rinderpest virus (RPV) belongs to what viral family and what viral genus?
Family Paramyxoviridae, genus Morbillivirus
What type of Virus is Rinderpest virus (RPV)
RNA-virus
How many serotypes does RPV have?
rinderpest virus
One serotype, three genetically distinct lineages.
1&2 are African
3 is Asian
Full cross-protection so antibodies due to one strain are good against all strains.
Rinderpest virus (RPV) inactive at what pH?
Inactivation at pH < 4.0 and > 10.0
Rinderpest virus (RPV) inactivation by
Most common disinfectants can inactivate.
Quickly inactivated in environment:
sensitive to light, dessication and UV-light
In what temp situation can Rinderpest virus (RPV) remain viable?
Can remain viable for long periods in chilled or frozen tissues.
Host range of RPV?
most cloven-hooved animals (Artiodactyla)
define Artiodactyla
an order of mammals that comprises the even-toed ungulates (cloven-hooved mammal)
species particularly susceptible to RPV?
& species mildly susceptible to RPV?
Particularly susceptible: cattle, water buffalo, yaks, African buffalo, giraffes, warthogs and Tragelaphinae (= Spiral-horned antelope pictured).
Mildly susceptible: sheep, goats
Morbidity of RPV
Morbidity is high at 100%.
Factors affecting mortality?
and what is the mortality rate of RPV?
Mortality depends on virus strain, animal (e.g. breed) and environment.
E.g. mortality rate is 100% in European cattle breeds and with peracute strains,
20-30% mortaliry in zebu cattle and acute strains,
and 0% in zebu cattle with mild strains.
Initial mortality 10-20%.
Transmission RPV?
Direct contact
(Close) indirect contact – fomites possible.
Route: via epithelium of the upper or lower respiratory tract
Infected animals do not become carriers!
Excretion of RPV?
Tears, nasal discharge, saliva, urine and faeces.
Blood and all tissues are infectious before clinical signs appear!
Most infectious period 1-2 days before clinical signs and 8-9 days after onset of clinical signs.
Incubation period of RPV?
3-15 days (usually 4-5 days)
Forms of RPV?
classic, peracute, subacute, atypical
The 4 D’s of Rinderpest:
- Depression
- Diarrhea
- Dehydration
- Death
Classic clinical signs of RPV in cattle (4-5)
Pyrexia,
“crying cow”/excessive lacrimation
erosive stomatitis,
gastroenteritis,
dehydration and death
RPV disease is Divided into stages: (4)
Prodromal period (ca 3 days)
Erosive phase
GI-signs phase
Death in 6-12 days
Describe PERACUTE RPV disease?
Young and newborn animals
High fever ( > 40⁰C),
congested mucous membranes.
Death in 2-3 days.
Describe subacute RPV disease? (2)
mild clinical signs, low mortality
(poss. “crying cow”/excessive lacrimation
erosive stomatitis etc.)
Describe atypical RPV disease? (2)
irregular pyrexia, mild or no diarrhea
Clinical signs of RPV in sheep & goat (4-5)
Variable signs: pyrexia, anorexia and minor ocular discharge
Sometimes diarrhea
Clinical signs of RPV in pigs (3)
Pyrexia, anorexia and prostration (laying down exhausted)
Erosions of buccal mucosa
Diarrhea
Post mortem signs of RPV
Oesophagus: brown and necrotic foci
LN: swollen and edematous
Gall bladder: hemorrhagic mucosa
Lungs: emphysema, congestion and areas of pneumonia
Post mortem GI lesions of RPV
Omasum: rare erosions and hemorrhages
Small intestine, abomasum, cecum and colon: necrosis, edema and congestion, “tiger/zebra striping”.
DDx in case of RPV
BVD (bovine viral diarrhea)
Malignant catarrhal fever
IBR (infectious bovine rhinotracheitis)
VS (vesicular stomatitis)
FMD
Salmonellosis
Johne’s disease
Bluetongue
Peste des petits ruminants
Material for diagnosis of RPV (3)
Blood
Spleen, lymph nodes
Ocular/nasal discharge
How to differentiate FMD vesicles from RPV vesicles?
In FMD, the vesicles/lesions are round and can be found on the feet and mammary glands too.
In RPV, the lesions are not neatly round but more spread/diffuse and can be necrotic.
(also excessive lacrimation is not seen in FMD but is in RPV)
Laboratory analysis for diagnosis of RPV (3)
Virus isolation
Antigens
RNA
Treatment for RPV
no treatment
vaccine exists: is live attenuated
control strategy for RPV (4-5)
Strategy: “stamping out”
Quarantines and movement control.
Decontamination of infected premises.
Intensive focal vaccination
Ring-vaccination during outbreak possible.
CBPP
Contagious bovine pleuropneumonia
Contagious bovine pleuropneumonia is caused by what pathogen?
the bacteria Mycoplasma mycoides subsp. mycoides
Contagious bovine pleuropneumonia (CBPP) is a
highly contagious mycoplasmosis, caused by Mycoplasma mycoides subsp. mycoides, characterized by pneumonia and other respiratory signs.
Contagious bovine pleuropneumonia (CBPP) is a highly contagious mycoplasmosis, caused by Mycoplasma mycoides subsp. mycoides, characterized by
pneumonia and other respiratory signs.
MmmSC
an abbreviation that refers to the agent causing CBPP (contagious bovine pleuropneumonia)
“Mycoplasma mycoides subsp. Mycoides Small Colony type” = MmmSC
MmmSC lineages
“Mycoplasma mycoides subsp. Mycoides Small Colony type” = MmmSC
Three main lineages: African and European lineages
Describe MmmSC phenotype and resistance profile.
“Mycoplasma mycoides subsp. Mycoides Small Colony type” = MmmSC
No cell walls
Pleomorphic
Resistant to AB-s of the beta-lactam group (e.g. penicillin).
Mycoplasma mycoides subsp. Mycoides is Inactivated by (3)
acid and alkaline pH.
Quickly inactivated in environment.
Most common disinfectants can inactivate it too.
Mycoplasma mycoides subsp. Mycoides does not survive in what?
And does survive in what?
typical meat or meat products (fresh/refridgerated).
But can survive in frozen meat: >10 years
Does not survive outside the animal for more than a few days in nature.
Host range of CBPP (contagious bovine pleuropneumonia): (4 points)
Cattle: both Bos taurus and Bos indicus (e.g. Zebu) are main hosts.
Asian buffalo, captive bison and yak.
What animals are naturally resistant to CBPP?
And what animals don’t show illness despite infection?
Wild bovids and camels are naturally resistant.
Sheep and goats can be naturally infected but no clear associated pathology in them.
Morbidity of CBPP (contagious bovine pleuropneumonia):
Varies by breed, general health and management systems.
Morbidity in susceptible populations <100%.
25% of recovered animals may become carriers.
Mortality of CBPP (contagious bovine pleuropneumonia):
Mortality varies 30-80%.
Secondary factors in overall health infuence (nutrition and parasitism).
25% of recovered animals may become carriers
CBPP (contagious bovine pleuropneumonia) excretion: (4-5)
Via respiratory tract,
Saliva,
urine,
fetal membranes,
uterine discharges.
CBPP (contagious bovine pleuropneumonia) transmission: (3-4)
Aerosols/ droplets (close contact).
Direct contact
Transplacental
Route: inhalation of infected droplets
Nonclinical bovine carriers of CBPP may shed the virus for how long?
Nonclinical bovine carriers with chronic infection are a major source of infection, and
may retain viable organisms in encapsulated lung lesions (sequestra) for up to 2 years.
Incubation period of CBPP?
The incubation period is highly variable, between 21 to 180 days (so up to 6 months) depending primarily on the susceptibility of the animal.
Forms of CBPP?
acute and chronic (also subclinical)
Clinical signs of acute CBPP? (3ish)
Lethargy, anorexia, fever, cough and extended head/neck.
Salivation, nasal and eye discharge.
Thoracic pain, reluctance to move; elbow abduction, moaning during expiration.
Increased respiratory rate.
Clinical signs of chronic CBPP? (2-3)
Less obvious signs of pneumonia – may cough with exercise.
Emaciation, recurrent mild fever.
Calves: polyarthritis +/- pneumonia
Subclinical carriers’ signs of CBPP?
Ha gotcha. No signs if subclinical, but act as carriers and can transmit.
Post mortem signs of CBPP in thoracic cavity? (5)
Large amounts of straw-colored serous fluid (up to 10L).
Enlarged LNs.
Gross pathologic lesions of the lung – unilateral.
Marbled appearance of the lungs.
Acute and chronic lesion in the interlobular septa.
Fibrosis
Encapsulated sequestra
Post mortem signs of CBPP in joints?
Joints enlarged – proliferation of connective tissue.
Tendosynovitis; arthritis
DDx for CBPP? (4)
Rinderpest (because of the lacrimation in both)
Pasteurellosis
Tuberculosis
FMD (because salivation in first stage of disease is similar, otheriwse not similar)
Material for diagnosis of CBPP? (3)
Fluid from thoracic cavity
Lung tissue
Lymph nodes
Laboratory analyses for diagnosis of CBPP? (4)
Culture
Immunological tests
PCR
Serology (ELISA)
Treatment of CBPP?
Tx only in endemic areas (africa) for reduction of severity of clinical signs and reduction in transmission.
ABs not affective
Vaccination – attenuated vaccine (T1/44 strain) to eradicate the dz.
Strategies for control of CBPP? (5)
Strategy during outbreak: “stamping out”
Quarantine and restriction of movements
Test & slaughter
Disinfection: 3% Sodium hypochlorite
Vaccination – attenuated vaccine (T1/44 strain) to eradicate the dz
In what countries in CBPP a problem?
sub-saharan africa
“The disease is endemic in most of the pastoral cattle herds of Western, Central, and Eastern Africa, Angola, and Northern Namibia.”
LSD =
Lumpy skin disease
Lumpy skin disease virus (LSDV)
4 alt. names for Lumpy skin disease
Pseudourticaria
Neethiling Virus Disease
Exanthema Nodularis Bovis
Knopvelsiekte
LUMPY SKIN DISEASE (LSD) is a
highly contagious viral disease of cattle, caused by Capripoxvirus, characterized by fever, skin nodules, and enlargement of lymph nodes.
LUMPY SKIN DISEASE (LSD) is highly contagious viral disease of cattle, caused by
Capripoxvirus.
LUMPY SKIN DISEASE (LSD) is highly contagious viral disease of cattle, caused by Capripoxvirus, characterized by
fever, skin nodules, and enlargement of lymph nodes.
Lumpy skin disease virus (LSDV) belongs to what family and genus?
Family Poxviridae, genus Capripoxvirus
LSDV is what type of virus?
Serotypes?
Related to what pathogen?
DNA-virus
One serotype.
Closely related to sheep pox virus and goat pox virus.
Cannot be differentiated with serology
LSDV survival in the environment. (3)
Very resistant in the environment
Seasonal variability: late summer-early fall
Cyclic: occurs every 5-6 years
Host range of LSDV?
cattle
Bos taurus > Bos indicus (Zebu)
Morbidity of LSDV?
Morbidity 3-85%
Dependent on the presence of insect vectors and host susceptibility.
Calves and lactating cows most susceptible.
Mortality of LSDV?
Mortality 1-3%
In outbreaks, still <20%.
Excretion of LSDV? (6)
Excretion: cutaneous lesions, saliva, respiratory secretions, milk, semen.
Shedding in semen can last long: >5 months post infection resolution.
Transmission of LSDV? (2-4)
Vectors: biting insects (Direct contact)
Fomites (low risk)
Route: cutaneous
One report of placental transmission.
Incubation period of LSDV?
2-5 weeks
Clinical signs of LSDV?
Fever
Nodules on the skin and mucous membranes (within 2 days).
- 1-7 cm in size; full thickness of the skin
- Head, neck, udder, genitalia, perineum and legs
Characteristically inverted conical zone of necrosis that become separated from the adjacent skin (“sit-fasts”).
Can occur also in GI tract, trachea and lungs
LN enlarged, oedematous
Additional ambiguous signs of LSDV? (ca 5)
Additional signs:
Feed intake and milk yield drop; emaciattion.
Rhinitis, conjuntivitis, keratitis.
Ocular, nasal discharges (serous or mucopurulent).
Infection and necrosis of tendons resulting in lameness
Abortions, temporary/permanent sterility
Recovery from LSDV?
Recovery: slow (months)
Deep holes or scars on the skin
Post mortem signs of LSDV? (5)
Skin nodules; flat or ulcerative lesions.
Lungs: focal areas of atelectasis and edema
Synovitis, tendosynovitis – some animals
Enlarged lymph nodes
Aborted fetuses may be covered in lesions.
Describe the skin nodules found post mortem in LSDV? (3)
Grayish-pink, deep, with necrotic centers
Extend to subcutis and underlying skeletal muscle.
Congestion, hemorrhages and edema of the adjacent tissue.
Describe the ulcerative skin lesions found post mortem in LSDV? (+++)
Found on the mucous membranes of the oral and nasal cavities, pharynx, epiglottis, trachea and GI tract (espesh abomasum!).
Udder, urinary bladder, lungs, kidneys, uterus and testes too.
DDx for LSDV? (10)
Pseudo-lumpy skin disease/bovine herpes Mammillitis (teat & udder ulcers)
Dermatophilosis (“rain rot”)
Ringworm
Insect or tick bites
Hypoderma bovis infestation (larvae subepidermally)
Photosensitization
Bovine papular stomatits
Urticaria
Cutaneous tuberculosis (mycobacterium)
Suspect LSDV when…
Characteristic skin nodules, fever and enlarged superficial lymp nodes.
Mortality in usually low.
Material for diagnosis of LSDV? (3)
Blood
Skin biopsy; scabs, nodular fluid, skin scrapings
Skin lesions and lesions in the respiratory and GI tract
Laboratory analyses for diagnosis of LSDV? (4)
Virus isolation – cell cultures
Antigen detection – e.g. ELISA
PCR
Serology
Treatment for LSDV?
no treatment, only symptomatic care
Eradication strategies for LSDV? (6)
Quarantine, movement control
Depopulation of the infected and exposed animals
Proper disposal of carcasses
Disinfection
Insect control
Vaccination
Control strategies for LSDV?
Vaccination in endemic areas to control the disease.
Homologous live attenuated vaccine gives immunity for max 3 years.
