Serological evidence of co-circulation of West Nile and Usutu viruses in equids from western Spain.
Transbound Emerg Dis
; 68(3): 1432-1444, 2021 May.
Article
in En
| MEDLINE
| ID: mdl-32853452
ABSTRACT
West Nile virus (WNV) is a mosquito-borne emerging virus in Europe with capacity to cause neurological complications such as encephalitis or meningoencephalitis in humans, birds or equids. In Spain, WNV is actively circulating in mosquitoes, birds and horses in different regions, but never has been deeply studied in Extremadura. Therefore, the aim of this study was to evaluate the seroprevalence of WNV in equids of those areas and to analyse the risk factors associated with exposure to the virus. A total of 199 out of 725 equids presented antibodies against WNV by competition ELISA (27.45%), while 22 were doubtful (3.03%). Anti-WNV IgM antibodies were detected in 16 equids (2.21%), and 3 animals were doubtful (0.41%). All ELISA-reactive positive/doubtful sera (N = 226) were further tested by micro-virus neutralization test (VNT), and a total of 143 horses were confirmed as positive for WNV, obtaining a seroprevalence of 19.72% in equids of western Spain. In addition, specific antibodies against USUV were confirmed in 11 equids. In 24 equids, a specific flavivirus species (detected by ELISA test) could not be determined. The generalized linear mixed-effects models showed that the significant risk factors associated with individual WNV infection in equids were the age (adults) and hair coat colour (light), whereas in USUV infections, it was the breed (pure). Data demonstrated that WNV and USUV are circulating in regions of western Spain. Given the high WNV seroprevalence found in equids from the studied areas, it is important to improve the surveillance programmes of public health to detect undiagnosed human cases and to establish a vaccination programme in equid herds in these regions.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
West Nile Fever
/
Flavivirus Infections
/
Coinfection
/
Horse Diseases
Type of study:
Etiology_studies
/
Prevalence_studies
/
Prognostic_studies
/
Risk_factors_studies
Limits:
Animals
Country/Region as subject:
Europa
Language:
En
Journal:
Transbound Emerg Dis
Journal subject:
MEDICINA VETERINARIA
Year:
2021
Document type:
Article
Affiliation country:
Spain