Rinderpest Cattle Plague

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Rinderpest (Cattle Plague)

• Rinderpest (RP) is a contagious viral disease of
  cattle, domestic buffalo, and wildlife that is
  characterized by fever, oral erosions, diarrhea,
  lymphoid necrosis, and high mortality.

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Rinderpest

• Potential to harm?
• Agro-bioterrorism Is it really a new threat!
• Not really

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Where is the disease found naturally?

• Africa
• Middle east some pockets
• Asia some pockets

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How travel and animal movement introduces disease?

• Anecdotal references
• African pandemic in 17th and 18th century
• Turkey had an outbreak due to Iraqi invasion in
  20th century

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Etiology

• RP virus (RPV) is a single-stranded RNA virus
• Family Paramyxoviridae, genus Morbillivirus.
• There is only one serotype of RPV, but field
  strains vary widely in virulence, ease of
  transmission, and host affinity.

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RPV viral properties

• Relatively fragile virus
• The virus is very sensitive to heat and light.
• RPV is rapidly inactivated at pH 2 and 12 (10
  minutes)
• RPV is inactivated by glycerol and lipid
  solvents.

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Effective Disinfectants

• Strong acid and alkaline disinfectants and many
  common disinfectants, particularly the iodophores
  and bleach are effective

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Incubation Period

• The incubation period varies with strain of RPV,
  dosage, and route of exposure.
• Following natural exposure, the incubation period
  ranges from 3 to 15 days but is usually 4 to 5
  days.

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Transmission

• Secretions and excretions contain large
  quantities of virus.
• Direct contact or indirect contact.
• Aerosol transmission of RP is not significant.
• Properly vaccinated animals are immune for life.
• No vertical transmission, arthropod vector, or
  carrier state.

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Rinderpest Forms of disease

• Peracute
• No signs of disease, death in 2-5 days, fever and
  congestion of oral mucosa
• Acute or classical form
• Depression, Diarrhea, Dehydration, Death (12-15
  days)
• Mild or transient form
• Can be missed

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Clinical signs

• Salivation excessive frothy
• Fever of 40 to 41 .1 C
• Serous oculonasal discharge
• Leukopenia

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Gross lesions Oral cavity
Necrosis and erosion of the gum above the dental
pad and inside the upper lip
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Erosions in the inside of the upper lip
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Gross lesions Intestine
Two necrotic Peyer's patches.
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An eroded Peyer's patch. The white foci in the
eroded Peyer's patch are necrotic material
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Hemorrhage in Colon
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Rectum - Hyperemia of the longitudinal folds
(zebra striping)
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Microscopically
L.N. Lymphoid Necrosis
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Mesenteric L.N. Lymphoid Necrosis and Syncytia
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L.N. Lymphoid Necrosis and Syncytia
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Intestine Changes in Peyers patches and mucosa
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Morbidity and Mortality

• In the classic form of RP, morbidity and
  mortality in a naive population of cattle can be
  very high.

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Differential Diagnosis

• BVD most important
• Others to be considered
• FMD
• IBR
• Peste Des Petits Ruminants

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Specimens for Laboratory
- Collect samples from animals showing fever
- Blood in EDTA or heparin - Blood for
serum - Swabs containing lacrimal fluid -
Necrotic tissue from the oral cavity -
Aspiration biopsies of superficial lymph nodes
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Contd

• Slaughter of febrile animal (FADD)
• Necropsy dead animal (FADD)
• Spleen
• Lymph nodes
• Tonsil
• All tissues in 10-percent formalin
• Transport of specimens to the laboratory on wet
  ice, not frozen.
• Dry ice shipment for VI/serology to Plum Island
  NY.

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Tests for diagnosis

• Virus Isolation-using primary BKCC or Vero cells
• VN, FA, IPeroxidase.
• Serology ELISA, AGID
• AGID or CIE from spleen, lymph node, necrotic gum
  epithelium, and even lacrimal swabs for Antigen

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Control and Eradication

• Biosecurity
• Control on movement
• Vaccination
• Slaughter

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Vaccination

• Lapinized (China and Korea)
• Avianized /Lapinized (Korea)
• Caprinized (India)
• Cell-culture-adapted
• (Africa, Middle East, India)

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Vaccine stability

• Cell culture vaccines are less stable
• Immunization each year of calves up to three
  years
• Once immuneLifelong immunity

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Can RP be used as BT agent?

• Less likely!