Antibodies against some viruses of domestic animals in southern African wild animals.

The researchers tested for antibodies against 16 common domestic animal diseases in 24 species of South African wild animals. They found positive results for 12 diseases but none for equine influenza, equine infectious anaemia, equine viral arteritis and Rift Valley fever, which are generally absent in South Africa. Their results varied by animal species and geographic region.

Objective of the study

• The study aimed to investigate the presence of antibodies against diseases common in domestic animals within 24 species of South African wild animals. This was done to understand how diseases pass between domestic and wild animals and monitor the potential for outbreaks in local wildlife populations.

Antibody Testing

• The researchers tested for antibodies against 16 common animal diseases. The presence of antibodies indicates past exposure to the disease. They found evidence of antibodies for 12 out of 16 diseases tested.
• The remaining 4 diseases, namely equine influenza, equine infectious anaemia, equine viral arteritis, and Rift Valley fever did not show the presence of any antibodies.
• This suggested these four diseases are absent in the regional habitat, supporting previous observational data that these diseases are not prevalent in South Africa.

Variability Across Species

• There was variation in the response to antibodies across different species, ranging from zero to 16 species being found positive for a specific virus.
• Particularly, crocodiles and warthogs were negative for all tested antibodies.
• On the contrary, antibodies against Wesselsbron and bovid herpes virus-1 were present in 16 animal species.
• Antibodies for horse-specific viruses were found almost exclusively in zebras. However, in the case of African horsesickness, even though elephants showed signs of an immune response, no neutralizing antibodies could be found in their sera.
• Zebras also showed antibodies for Wesselsbron and Akabane diseases, typically known to affect ruminants.

Geographical Variation

• The antibodies were found across all South African vegetation zones.
• However, a notable large proportion of viruses were more prevalent in the high-rainfall zone of KwaZulu-Natal. This indicates that the biodiversity of the region or specific environmental conditions could be more conducive to the transmission of disease.