West Nile Fever,
Portugal
Information received on 03/09/2015 from Prof. Dr Álvaro Mendonça, Director General, Direcção Geral de Alimentação e Veterinária, Ministério da Agricultura E do Mar, Lisboa, Portugal
Summary
Report type Immediate notification
Date of start of the event 21/08/2015
Date of confirmation of the event 31/08/2015
Report date 03/09/2015
Date submitted to OIE 03/09/2015
Date event resolved 31/12/2015
Reason for notification Recurrence of a listed disease
Date of previous occurrence 13/01/2011
Manifestation of disease Clinical disease
Causal agent West Nile virus
Nature of diagnosis Clinical, Laboratory (basic), Laboratory (advanced)
This event pertains to a defined zone within the country
Related reports Immediate notification (03/09/2015)
Follow-up report No. 1 (06/05/2016)
New outbreaks (3)
Outbreak 1 (WNF001/2015) LOULÉ - CH01, N.a., Dsvr Do Algarve
Date of start of the outbreak 21/08/2015
Outbreak status Resolved (31/12/2015)
Epidemiological unit Farm
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Equidae 18 1 0 0 0
Affected population Horses kept in an equestrian center. Only one horse showed clinical signs, namely ataxia.
Outbreak 2 (WNF002/2015) FARO - CH01, N.a., Dsvr Do Algarve
Date of start of the outbreak 24/08/2015
Outbreak status Resolved (31/12/2015)
Epidemiological unit Farm
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Equidae 54 1 0 0 0
Affected population Horses kept in an equestrian center. Only one horse showed clinical signs and is responding to treatment.
Outbreak 3 (WNF003/2015) LOULÉ - CH02, N.a., Dsvr Do Algarve
Date of start of the outbreak 24/08/2015
Outbreak status Resolved (31/12/2015)
Epidemiological unit Farm
Affected animals
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Equidae 10 2 0 0 0
Affected population Horses kept in an equestrian center. It was referred by the owner that initially two animals showed clinical signs. One of the animals completely recovered. The other animal still presented mild signs.
Summary of outbreaks Total outbreaks: 3
Total animals affected
Species Susceptible Cases Deaths Killed and disposed of Slaughtered
Equidae 82 4 0 0 0
Outbreak statistics
Species Apparent morbidity rate Apparent mortality rate Apparent case fatality rate Proportion susceptible animals lost*
Equidae 4.88% 0.00% 0.00% 0.00%
*Removed from the susceptible population through death, destruction and/or slaughter
Epidemiology
Source of the outbreak(s) or origin of infection
  • Vectors
  • Epidemiological investigation ongoing
Epidemiological comments A clinical suspicion of a probable case of West Nile fever in a human patient was communicated by the National Health Authority. Clinical, epidemiological and serological surveillance was implemented in order to access the possible presence of West Nile virus in susceptible species in the area. Voluntary vaccination will be implemented in the area. Outbreak at Loulé – CH02 is a secondary outbreak related to outbreak at Loulé – CH01.
Control measures
Measures applied
  • Disinfection / Disinfestation
  • Dipping / Spraying for control of vectors or parasites
  • Quarantine
  • Surveillance within containment and/or protection zone
  • Zoning
  • Control of vectors
  • Vaccination permitted (if a vaccine exists)
  • Treatment of affected animals (Symptomatic treatment)
Measures to be applied
  • No other measures
Diagnostic test results
Laboratory name and type Species Test Test date Result
National Institute for Agrarian and Veterinary Research (INIAV) (National laboratory) Equidae antibody detection ELISA 31/08/2015 Positive
National Institute for Agrarian and Veterinary Research (INIAV) (National laboratory) Equidae IgM-capture ELISA 31/08/2015 Positive
National Institute for Agrarian and Veterinary Research (INIAV) (National laboratory) Equidae real-time reverse transcriptase/polymerase chain reaction (RRT-PCR) 31/08/2015 Negative
National Institute for Agrarian and Veterinary Research (INIAV) (National laboratory) Equidae seroneutralization test (SNT) 31/08/2015 Positive
Future Reporting
The event is continuing. Weekly follow-up reports will be submitted.
Map of outbreak locations