Spirocercosis in Wildlife: Insights for Conservation

Nematodes in the genus Spirocerca, transmitted by dung beetles, infect both domestic dogs (Canis familiaris) and a multitude of wild carnivore species worldwide. Spirocerca infections in wild carnivores and their potential implications for conservation are not fully understood. This review aimed to analyze existing research on spirocercosis in wildlife and to highlight key differences between spirocercosis in wild and domestic carnivores. Spirocerca spp. have been detected in 35 wild host species in 31 countries across five continents. Typical pathologic signs of infection include aortic aneurysms, gastric and esophageal nodules, and aberrant migration within the thorax and abdomen. Complications seen in domestic dogs, such as vertebral spondylitis and hypertrophic osteopathy, have not been observed in wildlife. The reasons for these differences are not fully understood, but hypotheses include a relatively immature immune system in dogs, differences in diet, and evolved resistance to infection in wild hosts. Findings indicate that spirocercosis may not greatly impact healthy wild populations but could be devastating for critically endangered species. Future research should focus on screening for spirocercosis in wildlife after routine culling by using molecular methods to identify the species of Spirocerca nematodes instead of relying solely on morphologic characteristics.