Herpesvirus Flashcards
How is herpesvirus type-1 (EHV-1) is transmitted in horses?
The transmission mainly occurs by the respiratory route through nasal or conjunctival secretion contaminated with the virus, and by direct contact with aborted fetuses, fetal membranes and fluids, and various secretions and excretions of congenitally infected foals. Clinical cases are more infective in the first week of infection. Virus shedding occurs from 7 to 15 days in naive individuals. Transplacental infection occurs as well, but in most cases in late term (final trimester) will result in abortion. An infection occurring in a very late pregnancy might not cause abortion, but the the foal can be born with a fatal pneumonitis. In rare cases, EHV-1 has been found in the semen of Stallions and in an embryo from a donor.
What are the clinical signs fo EHV-1 respiratory disease?
- Upper respiratory infection
- Fever (39-41 C)
- Leukopenia involving both lymphopenia and neutropenia.
- Serous to mucous purulent nasal discharge
- Conjunctivitis
- Anorexia
- Depression
- Occasional coughing
- Enlargement of mandibular and retropharyngeal area
