By: Office International des Epizooties, Paris
Classification of the Causative Agent –
Virus family Paramyxoviridae, genus Rubulavirus
Temperature:
Inactivated by 56°C/3
hours,60°C/30
min
pH:
Inactivated by acid pH
Chemicals:
Ether sensitive
Disinfectants: Inactivated
by formalin & phenol
Survival:
Survives for long periods in feces
Epidemiology –
Hosts
· Many species of birds, domestic & wild
· Morality /morbidity rates vary among species & strains
· Chickens most susceptible poultry, ducks/geese least
· Carrier state may exist in psittacine & some wild birds
Transmission
· Direct contact with secretions, feces, from infected birds
· Contaminated feed, water, implements, premises, clothes
Sources of Virus
·
Respiratory discharges, feces
· All parts of the carcass
· Virus shed during incubation & convalescence
· Psittacines can shed virus intermittently for over 1 year
Diagnosis –
Incubation is four to six days
Clinical Diagnosis
·
Respiratory and/or nervous signs:
* gasping & coughing
* drooping wings, dragging legs, twisting of the head
& neck, circling,
depression, loss of appetite, paralysis
·
Partial or complete cessation of egg production
·
Abnormal eggs, watery albumen
·
Greenish watery diarrhea
·
Swelling around eyes & neck
·
Morbidity/mortality depend on strain, vaccine immunity, environmental
conditions & flock health
Prevention & Control –
No treatment
Medical Prophylaxis
·
Vaccination with live and/or oil emulsion vaccine
· Live B1 & La Sota strains administered in drinking water
· Other infections may aggravate vaccine reaction
Sanitary Prophylaxis
·
Strict isolation of outbreaks
·
Destruction of all infected & exposed birds
·
Thorough cleaning and disinfection of premises
·
Proper carcass disposal (bury or burn)
·
Respiratory discharges, feces
·
All parts of the carcass
·
Pest control in flocks
·
Depopulation followed by 21 days before restocking
·
Avoid contact with birds of unknown health status
·
Control of human traffic
·
1 age group per farm breeding recommended
