Original scientific paper
An outbreak of equine influenza (H3N8) in Croatia in 2004 caused by South American lineage
Ljubo Barbić
Janet M. Daly
Nevenka Rudan
Snježana Kovač
Vladimir Savić
Slavko Cvetnić
Josip Madić
Abstract
Several epizootics of equine influenza have been reported in Croatia in the past. Both subtypes, A/equine-1 (H7N7) and A/equine-2 (H3N8) were isolated. An outbreak of equine influenza in 2004, in racehorses on Zagreb hippodrome is described. Both unvaccinated and vaccinated horses showed clinical signs of respiratory disease. By cross HI test and serological examinations of paired sera of apparently affected horses, equine influenza (H3N8) virus was detected. Antigenic and genetic analysis of isolated viruses revealed the occurrence of South American sublineage of equine-2 (H3N8) influenza virus. The results presented in this work demonstrated that the HA1 gene sequence of the 6 isolates that were sequenced had only a single, non-coding nucleotide substitution among them. When the amino acid sequences of the Croatian isolates were aligned with a virus isolated in the UK during a widespread outbreak in the spring of 2003 (Newmarket/5/03), only a single amino acid substitution in the signal sequence was seen.
Keywords
Influenca konja; Serotip H3N8; Južnoamerička podlinija
Hrčak ID:
7744
URI
Publication date:
25.11.2006.
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