Equine Herpesvirus Type 1 Myeloencephalitis in the Brazilian Amazon
José Diomedes Barbosa,
André de Medeiros Costa Lins,
Henrique dos Anjos Bomjardim,
Natália da Silva e Silva Silveira,
Camila Cordeiro Barbosa,
Edsel Alves Beuttemmuller,
Marilene Farias Brito,
Felipe Masiero Salvarani
Affiliations
José Diomedes Barbosa
Instituto de Medicina Veterinária, Universidade Federal do Pará, Castanhal 68740-970, PA, Brazil
André de Medeiros Costa Lins
Instituto de Medicina Veterinária, Universidade Federal do Pará, Castanhal 68740-970, PA, Brazil
Henrique dos Anjos Bomjardim
Instituto de Estudos do Trópico Úmido (IETU), Universidade Federal do Sul e Sudeste do Pará (Unifesspa), Xinguara 68557-335, PA, Brazil
Natália da Silva e Silva Silveira
Instituto de Medicina Veterinária, Universidade Federal do Pará, Castanhal 68740-970, PA, Brazil
Camila Cordeiro Barbosa
Instituto de Medicina Veterinária, Universidade Federal do Pará, Castanhal 68740-970, PA, Brazil
Edsel Alves Beuttemmuller
Centro de Ciências Agrárias, Universidade Estadual de Londrina (UEL), Londrina 86057-070, PR, Brazil
Marilene Farias Brito
Departamento de Epidemiologia e Saúde Pública (DESP), Instituto de Veterinária (IV), Universidade Federal Rural do Rio de Janeiro (UFRRJ), Seropédica 23890-000, RJ, Brazil
Felipe Masiero Salvarani
Instituto de Medicina Veterinária, Universidade Federal do Pará, Castanhal 68740-970, PA, Brazil
An investigative and epidemiological study was carried out for equine herpesvirus type 1 (HVE-1) in 10 outbreaks of neurological disease from different farms in the state of Pará, Brazil. 25 horses were studied: six male and 19 females, aged between one and 13 years. A necropsy of six horses was performed, and the others recovered either with or without treatment (T1—vitamin B1 + dexamentasone; T2—vitamin B1 + flunixim meglumine). Animals that received treatment recovered after eight days. The main clinical signs observed were motor incoordination, progressive paresis, thoracic and/or pelvic limbs abducted after induction of clinical examination, knuckling of the hind fetlocks, sagging and swaying of the hindquarters while standing or walking and paresis. All animals were positive: 88% (22/25) in nested PCR and 72% (18/25) in serum neutralization (including three negatives in serology). Focal brownish areas compatible with hemorrhage were found in the white and gray matter of the spinal cord of two animals. On histological analysis, there were perivasculitis and neutrophilic vasculitis in the gray matter of the spinal cord and brain. Based on the evidence, this work proves the circulation of HVE-1 in the Amazon biome, mainly in the state of Pará, Brazil.
