RESUMO
Since the emergence of West Nile virus (WNV) in North America in 1999, there have been several reports of WNV activity in Central and South American countries. To detect WNV in Brazil, we performed a serological survey of horses from different regions of Brazil using recombinant peptides from domain III of WNV. Positive samples were validated with the neutralisation test. Our results showed that of 79 ELISA-positive horses, nine expressed WNV-specific neutralising antibodies. Eight of the infected horses were from the state of Mato Grosso do Sul and one was from the state of Paraíba. Our results provide additional evidence for the emergence of WNV in Brazil and for its circulation in multiple regions of the country.
Assuntos
Anticorpos Antivirais/sangue , Doenças dos Cavalos/epidemiologia , Febre do Nilo Ocidental/veterinária , Vírus do Nilo Ocidental/imunologia , Animais , Brasil/epidemiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Doenças dos Cavalos/diagnóstico , Doenças dos Cavalos/virologia , Cavalos , Testes de Neutralização , Estudos Soroepidemiológicos , Febre do Nilo Ocidental/diagnóstico , Febre do Nilo Ocidental/epidemiologia , Vírus do Nilo Ocidental/isolamento & purificaçãoRESUMO
INTRODUCTION: West Nile virus (WNV) is a flavivirus with a natural cycle involving mosquitoes and birds. Over the last 11 years, WNV has spread throughout the Americas with the imminent risk of its introduction in Brazil. METHODS: Envelope protein domain III of WNV (rDIII) was bacterially expressed and purified. An enzyme-linked immunosorbent assay with WNV rDIII antigen was standardized against mouse immune fluids (MIAFs) of different flavivirus. RESULTS: WNV rDIII reacted strongly with St. Louis encephalitis virus (SLEV) MIAF but not with other flaviviruses. CONCLUSIONS: This antigen may be a potentially useful tool for serologic diagnosis and may contribute in future epidemiological surveillance of WNV infections in Brazil.
Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Proteínas Recombinantes/imunologia , Proteínas do Envelope Viral/imunologia , Vírus do Nilo Ocidental/imunologia , Animais , Brasil , Ensaio de Imunoadsorção Enzimática , CamundongosRESUMO
INTRODUCTION: West Nile virus (WNV) is a flavivirus with a natural cycle involving mosquitoes and birds. Over the last 11 years, WNV has spread throughout the Americas with the imminent risk of its introduction in Brazil. METHODS: Envelope protein domain III of WNV (rDIII) was bacterially expressed and purified. An enzyme-linked immunosorbent assay with WNV rDIII antigen was standardized against mouse immune fluids (MIAFs) of different flavivirus. RESULTS: WNV rDIII reacted strongly with St. Louis encephalitis virus (SLEV) MIAF but not with other flaviviruses. CONCLUSIONS: This antigen may be a potentially useful tool for serologic diagnosis and may contribute in future epidemiological surveillance of WNV infections in Brazil.