Equine Influenza
Definition
Etiology
- Type A influenza virus
- First isolated and identified in 1958 in Czechloslovokia (A/Equi 1 Serotype)
- Second serotype -1963 in Miami, USA (A/ Equi2)
- The virus is of two serotypes based on antigenic differences in their haemagglutination
- First recorded in India in 1987
Susceptibility
- All age groups including newborn foals of 2-6 months age
- Two years and younger horses are highly susceptible
Mortality
Morbidity
Transmission
- Droplet inhalation
- Fomites-Direct contact
Pathogenesis
- Inhalation of virus, multiplies in epithelial cells of upper respiratory tract causes erythema, oedema and focal erosions
- Viraemia is brief and mild
- Deciliation causes secondary bacterial infection and complicate the condition
Clinical signs
- Incubation period -2-3 days
- Fever (1010-1060F)
- Cough –Dry to moist for 1-3 weeks
- Watery nasal discharge
- Depression
- Reluctance to move
- Anorexia
- Deaths in young foals due to pneumonia
Lesions
- Erosions in mucosa of nose, pharynx, larynx, trachea
- Lungs-peribronchitis , periarteritis, broncho pneumonia
Diagnosis
- Serological tests- Complement fixation test
- Haemagglutination test
- Serum neutralization
- ELISA
- Identification of viral antigen by immunostaining
Differential diagnosis
- Equine rhino pneumonitis affects only young horses
- Equine viral arteritis produces oedema of limbs
- Colic
- Diarrhoea
- Conjunctivitis
- Photophobia
- Abortion
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Last modified: Saturday, 17 December 2011, 10:05 AM