African horse sickness outbreaks in Namibia from 2006 to 2013: clinical, pathological and molecular findings.

The research article presents an analysis of African horse sickness (AHS) outbreaks that occurred in Namibia from 2006 to 2013. It details the clinical, pathological, and molecular findings of the illness in horses, with insights on disease diagnosis and potential controls.

Collaborative Research and Methodologies

• The study was a combined effort from the Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise, the Namibian Ministry of Agriculture Water and Forestry, and the Namibian National Veterinary Association.
• A total of 92 horses that exhibited varying clinical manifestations of AHS were investigated. The known clinical forms included peracute/acute, sub-acute, and mild AHS fever.
• In instances where clinical data was unavailable, for example, when horses were found dead, post-mortem examinations were conducted. During autopsy, common pathological findings such as pulmonary and subcutaneous oedema, haemorrhages, and lymph node enlargement were recorded.

Diagnosis and Viral Findings

• Laboratory testing played a crucial role in confirming the diagnosis of AHS. The virus causing AHS (AHSV) was isolated in 50 of the 92 studied horses.
• Various serotypes of the AHSV, including 1, 2, 4, 6, 7, 8 and 9, were identified among the afflicted horses.
• Phylogenetic analysis was performed on the genomic sequences of the S10 strain of the identified viruses. The results of this analysis revealed that the AHSV strains in Namibia were similar to those recently seen in South Africa.

Significance of the Research

• This comprehensive investigation into the AHS outbreaks in Namibia offers practical insights into the clinical, pathological, and laboratory aspects of the disease.
• The findings of the study can be of immense value in the differential diagnosis and eventual control of AHS, particularly in areas that are currently free from the illness.
• The identification of the various AHSV serotypes and the phylogenetic analysis of the viral strains contribute to the global understanding of AHS, potentially aiding the development of future preventive measures.