Poxvirus Flashcards
Cowpox
Species Affected
Cattle
Hu- most freq. by cat/rodent
rodents are reservior,
Cowpox
Spread
via contact through skin lesion
Zoonotic!
Cowpox
Clinical signs
*Hu- Milker’s nodules, udder, replicates in skin black crusts, long lasting immunity, face& hands
*Ru: mild fever, nodules on teats, scrotum and mouth
*Fe: mainly in head& limbs
Zoonotic!
Cowpox
Target Organs
Skin
3-7d incubation
Zoonotic!
Cowpox
Histopathology
Histopathology: Guarnieri bodies
Zoonotic!
Cowpox
Treatment
Symptomatic treatments
Antibiotic treatment
Zoonotic!
Cowpox
Immunisation
Vaccine for cats
Zoonotic!
Camelpox
Clinical signs
- Generalised infection, Severe skin lesions, pneumonia, blindness
- In young animals: up to 25% mortality
Buffalopox
Clinical signs
Skin lesions on the cheeks, udder, scrotum
Mousepox / Ectromelia
Clinical signs
- Generalised disease with high mortality
- Skin erosions, loss of extremities
- Subclinical infections in enzootic populations
Smallpox / Variola vera
- Humans, No animal reservoirs
- Especially children
- skin lesions, pneumonia, generalized no SC
- vaccine: mutant cowpox - stopped since eradication
Horsepox
Mild lesions, nodules on the muzzles and on the head
Pseudocowpox
Species Affected
Cattle & Humans
Pseudocowpox
Spread
infected animal, quick spread, indirect transmission via milking machine
Pseudocowpox
Clinical signs
mild
- Cow :Teat: red skin papules but no vesicles, painful (impossible to milk), horse shoe remained scar
- Hu: Milker’s nodules
Pseudocowpox
Immunisation
No vaccine
No long immunity —> recurrent signs, outbreaks
1w incubation
Bovine papular stomatitis
Species affected
- Cattle and Humans
* ZOONOTIC
Bovine papular stomatitis
Most susceptible
*Cattle <1 year of age
Bovine papular stomatitis
Occurrence
Worldwide
Bovine papular stomatitis
Spread
*Introduction to the herd via an infected animal
Direct or indirect contact
*Most frequently in spring and early summer
*Severity of incidence is affected by host weakening factors (eg mycotoxicosis)
Bovine papular stomatitis
Pathogenesis
*No long immunity —> recurrent
signs, outbreaks
*Lesions may persist for 3-4 months
Bovine papular stomatitis
Clinical signs
- Usually mild —> lesions on the oral cavity, increased salivation, mild fever
- May be some difficulty eating —> may cause condition loss
- Lesions around external nares and oral cavity: gums, lips, nose —> red skin, tough, merging nodules, erosions —> round areas of congestion, later becoming necrotic in the centre and slightly depressed
- Rarely nodule formation on the udder of cows
- Usually heals spontaneously
Bovine papular stomatitis
Diagnosis
Clinical signs and Histopathology: Guarnieri bodies
Virus isolation
PCR
Serology (ELISA)
Bovine papular stomatitis
Treatment
*Symptomatic treatment
Bovine papular stomatitis
Prevention and immunity
- General management —>exclude weakening environmental factors
- No vaccine!
Contagious Pustular Dermatitis of sheep and goat
Species affected
- Sheep and Goat
* Humans–>Zoonotic!
Contagious Pustular Dermatitis of sheep and goat
Most susceptible
*All age groups, especially Suckling lambs and kids (100% morbidity)
Contagious Pustular Dermatitis of sheep and goat
Occurrence
worldwide
Contagious Pustular Dermatitis of sheep and goat
Spread
Introduction to the herd with sub clinically infected animals and fomites
Contagious Pustular Dermatitis of sheep and goat
Pathogenesis
- Infection through skin, oral mucosa —> oral lesions
* No long immunity —> recurrent signs, outbreaks
Contagious Pustular Dermatitis of sheep and goat
Primary replication
Incubation time of 3-9 days
Contagious Pustular Dermatitis of sheep and goat
Clinical signs
- Lips, muzzle, tongue, gums: papules, scbs —> painful to eat!
- Teat lesions on ewe: painful —> the ewe does not let the lamb suckle
- Lesions on the reproductive mucosa: reproductive problems, no mating
- Lesions on limbs: lameness, complications with contagious with low (secondary infections)
- Economic losses of the herd
- Recovery within 4-6 weeks, without scars
Contagious Pustular Dermatitis of sheep and goat
Diagnosis
Clinical signs and Histopathology: Guarnieri bodies Virus isolation PCR Serology (ELISA)
Contagious Pustular Dermatitis of sheep and goat
Treatment
*Rinsing the mucosal surfaces with disinfectants, used of epithetizes
Remove scabs
*Local and systemic antibiotic therapy
*Virulent vaccine (live vaccine)
• Used in emergence, outbreak of infected close farms
• Vaccine causes skin scarification (no shedding) —> inject it in the inner thigh or ventral to the tail
• Giving nothing po will not hinder feeding —> no economic losses
• Recovery within 3 weeks, protection for 6 months
• Careful when vaccinating as the vaccine is zoonotic to humans!
Contagious Pustular Dermatitis of sheep and goat
Prevention and immunity
*Closed farming, testing of new entries and quarantine
*No selling from infected flocks—> relapsing signs due to travelling stress!
*In enzootic herds some maternal immunity to the newborns
*Virulent vaccine (live vaccine)
• Vaccinate ewes 6-8 weeks before parturition
• Vaccinate lambs at 2-3 days old and at 3 months old
*Mildly attenuated vaccine
• Skin scarification
• Vaccinate lamb/kid at 2 days old, repeat at 2 weeks old, at 3 months old and in every 6 months after that
Sheeppox and Goatpox
Species affected
*Sheep and Goat
ZOONOTIC and NOTIFIABLE
Sheeppox and Goatpox
Most susceptible
Lambs/kids
Immunosuppressed adults
Sheeppox and Goatpox
Occurrence
- Enzootic in Africa, Middle East, Asia
- Occasionally in Southern Europe
- Australia, America free
Sheeppox and Goatpox
Spread
- Typically airborne infection from wool, skin and fomites
* Quicker spread in stables than in pastures
Sheeppox and Goatpox
Pathogenesis
*Airborne infection —> Viraemia —> Visceral organs:
• Lungs, airways, stomach, kidney: proliferative foci
• Skin: pox nodules, no vesicles
• Pregnant ewes: abortion, delivery of ill foetus
*After recovery: long term immunity, maternal immunity in offspring
*Virus is shed by discharges, milk, crusts in acute stage
Sheeppox and Goatpox
Primary replication
- Respiratory mucosa
* Incubation time of 1 week
Sheeppox and Goatpox
Clinical signs
- Fever, general signs, conjunctivitis, serous nasal discharge
- Lambs/kids and weak adults may die during acute stage
- Nodules on skin within 1-2 days —> all around the body
- Respiratory signs, pneumonia with bacterial complications
- Condition loss, wool damages, milk production decrease
- Mortality: lamb/kid 70-80%; adults 5-10%
Sheeppox and Goatpox
Pathology and histology
- Skin, lung, kidney: lymphoma-like proliferative foci
- Airways, enteric mucosa: nodules, erosions
- Cytoplasmic inclusion bodies —> Guarnieri bodies
Sheeppox and Goatpox
Diagnosis
Clinical signs, lesions are diagnostic and characteristic but since disease is notifiable further tests are needed! Histopathology Virus isolation PCR Serology (ELISA
Sheeppox and Goatpox
Prevention and immunity
*Enzootic areas: attenuated vaccination given sc, 1-2 years protection
*Free areas:
• Avoid introductions (restrictions on imports)
• Emergence —> sanitary prophylaxis: destruction of all infected and exposed animals
Lumpy skin disease
Species affected
- Ruminants (cattle, sheep, goat, buffalo, giraffe, impala etc)
- ZOONOTIC and NOTIFIABLE
Lumpy skin disease
Occurrence
- Enzootic in Africa
* Outbreaks in Middle East and Asia
Lumpy skin disease
Spread
- Mechanically vectored by arthropods (mosquitos, flies)
* Direct contact, saliva contaminated feed
Lumpy skin disease
Pathogenesis
- Bite Infection
- Generalised in some animals
- After recovery, long term immunity; maternal protection for 6 months
Lumpy skin disease
Primary replication
- Entry site —> Insect bite
* Incubation time of 1-5 weeks
Lumpy skin disease
Clinical signs
*Local infection: Nodules in the skin
• Fever (even >41℃), general signs, rhinitis, conjunctivitis, salivation
• Decreasing milk production
• Painful, deep, 2-5cm well demarcated nodules on the skin:
• In the head, neck, udder, inguinal areas
• Present in all layers of the skin
• After 2 weeks: necrotic nodules —> fall out —> deep ulceration —> scars or secondary bacterial infections
• Enlarged lymph nodes, limb oedema
*Generalised infections:
• Nodules on the mucosal surfaces: mouth, enteric tract, trachea, lungs
• Ocular lesions: nodules, mucopurulent discharge, keratitis
• Abortion, skin lesions in new-borns
• Body condition loss, milk loss, skin useless for leather production
• High morbidity, low mortality
Lumpy skin disease
Diagnosis
Clinical signs, lesions are diagnostic and characteristic but since disease is notifiable further tests are needed! Histopathology Virus isolation PCR Serology (ELISA, not reliable!)
Lumpy skin disease
Prevention and immunity
*Enzootic areas: • Attenuated vaccine • Recombinant vaccine • Scarification, long-lasting immunity • Arthropod control, use of repellants *Free areas: • Avoid introduction (restriction on imports) • Emergence —> sanitary prophylaxis: destruction of all infected and exposed animals, arthropod control, emergency vaccination in 50km radius
Swinepox
Species affected
Pigs
Stonexen!
Swinepox
Most susceptible
All age groups, especially 2-8 week old piglets
Swinepox
Occurrence
*Worldwide
*In not well managed stocks, usually among traditional conditions (were the pigs are left out in the pasture)
Rare in industrial flock
Swinepox
Spread
*Mechanical vectors: lice, fleas —> pigs with long hair are prone to disease since lice will prefer long haired animals —> Hungarian Mangalica!
By direct contact to skin lesions in poor keeping conditions
Swinepox
Pathogenesis
- Bite infection
* After convalescence, long term immunity; maternal protection
Swinepox
Primary replication
- Entry site —> Insect bite
* Incubation time of 1-3 weeks
Swinepox
Clinical signs
*2-8 week old piglets:
• Usually benign, but may cause mortality
• In the beginning —> fever, inappetence, dullness —> followed by general signs (lesions around the body)
• Skin suffusions, red dots —> pox nodules (ears, belly, legs etc)
• Wet nodules —> pustules —> scabs (within 1 week of disease)
• Inner ear lesions —> meningitis
• Long lasting illness, lesions in different stages, bacterial complications
*In adult piglets:
• Mild or subclinical infection
Swinepox
Diagnosis
Clinical signs and
Histopathology: Guarnieri bodies
Virus isolation is difficult!
PCR
Swinepox
Treatment
Symptomatic treatments
Antibiotic treatment
Swinepox
Prevention and immunity
*General epidemiological rules:
• Management, hygiene, ectoparasite treatment
*No vaccine!
Myxomatosis
Species affected
Rabbits Natural hosts: Sylvilagus minensis, S.brasilensis, S.bachman
Myxomatosis
Most susceptible
*All age groups
*Domestic rabbits
European rabbit
*Cotton tailed rabbits—> subclinical infection
*European hare —> not usually susceptible
Myxomatosis
Occurrence
Worldwide
European and Asian virus has a different antigenic structure and can be transmitted orally
Myxomatosis
Spread
- Mechanical vectors: lice, fleas, flies —> can carry the disease for months
- Seasonality: autumn —> epizootic in few-year intervals
- Direct and iatrogenic transmission may occur
Myxomatosis
Pathogenesis
*Bite Infection:
• Day 1: Oedema at the site of entry (most likely ear skin)
• Day 2: Virus in lymph nodes
• Day 3 : Viraemia —> blood vessel damages —> virus in liver and spleen
• Day 4:Virus in other organs and tissues
• Day 5: Blepharoconjunctivitis
• Day 6: Onset of clinical signs (generalised skin, mucosa)
• Day 8-9: Typical signs with tumour-like regions
• Day 10: Death because of the capillary endothelial proliferation
Recovery by lysis of myxoma cells
Myxomatosis
Primary replication
- Entry site —> Insect bite and surrounding lymph nodes
* Incubation time of 6-7 day
Myxomatosis
Clinical signs
*Typical form:
• Gelatinous swellings especially in the head—> Lion head: eyelids, nose, lips and ears become oedematous to give a swollen head
• Cold-like signs —> Purulent nasal discharge, laboured breathing —>pneumonia
*Nodular form:
• Firm nodules, benign
• Develop on nose, ears and forefeet
*Conjunctival/respiratory/atypical form:
• Cold-like signs with no or mild swellings
Mortalities are seen after 1 week of illness
Myxomatosis
Pathology and Histopathology
*Typical form:
• Tumour-like tissue with subcutaneous tissue proliferations, wet surface
• Hydropic degeneration and vacuolisation in the cell with cytoplasmic inclusions
• Epithelial necrosis, corium oedema, proliferation of mesenchymal cells
• Lymph nodes, spleen: reticulum cell hyperplasia, lymphocytes damages
Myxomatosis
Diagnosis
Typical form: • Clinical signs and Pathology Atypical form: • Histopathology: Guarnieri bodies • Virus isolation • PCR
Myxomatosis
Prevention and immunity
*Sanitary prophylaxis:
• Closed farming
• Mosquito nets and arthropod control
*Outbreaks control:
• Movement restrictions
• Slaughter of affected animals
• Vaccinations in protection zone
*Vaccinations:
• Shope (hare) fibroma virus heterologous vaccine —> from 3 weeks of age, protects for 3-6 months
• Attenuated myxoma virus vaccine —> from 5 weeks of age, protects fro 1 year; vaccinate in early summer s.c.
• Recombinant vaccine —> RHDV surface antigens in myxoma virus vector
Fowlpox
Species affected
*A lot of bird species—> relative species
adaptation of the viruses
*Serological cross reactions —> partial cross protection!
Fowlpox
Most susceptible
*All age groups
*Diphtheric/Wet form: Mainly in chicken, in turkey less severe, in pigeons rare and in pheasants respiratory
signs only
*Canary and Parrots are likely to have the Acute Septicaemic form
*A-hypovitaminoses and other weakening factors may predispose
*Most industrial flocks are immunised at the first weeks of age —> mostly seen in private/ backyard chickens
Fowlpox
Occurrence
Worldwide
Fowlpox
Spread
- Introduction of virus via a carrier bird
- Wild birds play an important role
- Direct contact with faeces, food, drinking water, fomites
- Mechanical vectors: mosquitos, soft ticks —> can carry the disease for weeks
Fowlpox
Pathogenesis
*PO/Airborne/Through skin lesions
*Infection:
• (1) Homologous strains:
• Primary viraemia —> generalisation —> multiplication in visceral organs (can be fatal) —> secondary viraemia —> replication in skin and mucosal surface epithelia, flourishing (papules —> vesicles —> crusts —> scars)
•(2) Heterologous strains:
• Primary replication —> Local skin lesions
• (3)Intermediate/transient strains:
• Primary replication and viraemia but no secondary replication in visceral organs!
Fowlpox
Primary replication
Entry site
*Incubation period of 4-10 days; in canary it is shorter
Fowlpox
Clinical signs
*Cutaneous form
• Less severe and benign, mortality is low
• Usually on featherless skin (combs, eyelids, around the back, cloaca, legs); broiler —> all around the skin
• Firm nodules —> soften within 5-6 days and merge —> pastures —> scabs within 1-2 weeks —> scars (transient lesions)
• Condition losses, decreased egg production, mycoplasmosis activation
*Diphtheric or Wet form:
• Malignant and severe, high mortality
• Nose, mouth, pharynx, larynx, trachea mucosal lesions
• Alterations on the lungs and mucous membranes –> pustules, nodules, sometimes fibrin plaques
• General signs with fever, respiratory signs
• Shady mucosal surfaces, greyish-yellowish diphteric membranes
• secondary infections may occur
• Conjunctivitis, uveitis, sinusitis
*Mixed form:
• Cutaneous and Diphtheric
• Diverse severity
*Acute septicaemic form:
• Mortality without pox lesions —> mainly in canary
• Parrots —> rarely conjunctivitis, blepharitis, diarrhoea, respiratory signs, head skin ulcers
Fowlpox
Pathology and histopathology
Diphtheric form:
• Proliferative nodules at the larynx —> May be obstructive
• Tracheitis, diphtheric membranes
• Body condition loss, degeneration of visceral organs, pulmonary oedema, enteritis
• Epithel-proliferation, oedema, cytoplasmic inclusion bodies
Fowlpox
Diagnosis
Clinical signs and
Histopathology: Guarnieri bodies
Virus isolation
PCR
Fowlpox
Treatment
Antibiotic treatment against coinfections, especially mycoplasma
Fowlpox
Prevention and immunity
*Avoid introduction:
• Closed farming, quarantine, exclude wild birds
• Arthropod control
*Vaccinations:
• (1)Live attenuated fowlpox virus vaccines —-> chicken, turkey and pheasant
• Inject in skin of wing for chicken and pheasants, inject in skin of neck for turkeys; check after 1 week
• Usually at 3 months of age, sometimes younger (6-8 weeks old) —> repeat 2 months before laying period
•(2) Attenuated pigeonpox vaccine —> pigeon
• Inject in skin of the wing or rub into feather follicles
