Isolation of equid alphaherpesvirus 3 from a horse in Iceland with equine coital exanthema

• Published in: Acta Veterinaria Scandinavica
• Main Authors: Lilja Thorsteinsdóttir, Gunnar Örn Guðmundsson, Höskuldur Jensson, Sigurbjörg Torsteinsdóttir, Vilhjálmur Svansson
• Format: Article in Journal/Newspaper
• Language: English
• Published: BMC 2021
• Subjects: DNA polymerase gene; Glycoprotein G; PCR; Sequencing; Titration; Virus isolation; Veterinary medicine; SF600-1100; Iceland
• Online Access: https://doi.org/10.1186/s13028-021-00572-4; https://doaj.org/article/16821da72f574b99b5c85421f150af72

Abstract Equine coital exanthema (ECE) caused by equid alphaherpesvirus 3 (EHV-3) is a contagious venereal disease. It is characterized by the formation of papules, vesicles, pustules and ulcers on the external genitals of both mares and stallions. The Icelandic horse is the only breed in Iceland and has lived isolated in the country for over 1000 years. Three types of equine herpesviruses (EHV) have been found in Iceland, EHV-4, EHV-2 and EHV-5, while EHV-1 has never been detected. Symptoms resembling ECE have previous been observed in horses in Iceland, arousing suspicion of EHV-3 infection, but this has never been confirmed using virological methods. Samples were collected from a mare with papules on the vulva and inoculated in primary equine kidney cells. Cytopathic effects developed as rounded cells and syncytial formation. Polymerase chain reaction and sequencing of the partial glycoprotein G and DNA polymerase genes identified the isolated virus as EHV-3. On the basis of the findings, EHV-3 infection was verified for the first time in the native Icelandic horse population.