Background: Hippobosca longipennis (the 'dog louse fly') is a blood sucking ectoparasite found on wild carnivores such as cheetahs and lions and domesticated and feral dogs in Africa, the Middle East and Asia, including China. Known as an intermediate host for Acanthocheilonema dracunculoides and a transport host for Cheyletiella yasguri, it has also been suggested that H. longipennis may be a vector for other pathogens, including Acanthocheilonema sp.? nov., which was recently reported to infect up to 48% of dogs in northern India where this species of fly is known to commonly infest dogs. To test this hypothesis, hippoboscid flies feeding on dogs in Ladakh in northern India were collected and subjected to microscopic dissection.
Results: A total of 12 infective larvae were found in 10 out of 65 flies dissected; 9 from the head, 2 from the thorax and 1 from the abdomen. The larvae averaged 2, 900 (± 60) μm in length and 34 (± 5) μm in width and possessed morphological features characteristic of the family Onchocercidae. Genetic analysis and comparison of the 18S, ITS-2, 12S and cox-1 genes confirmed the identity of the larvae as the Acanthocheilonema sp.? nov. reported in dogs in Ladakh.
Conclusion: This study provides evidence for a potential intermediate host-parasite relationship between H. longipennis and the canine Acanthocheilonema sp.? nov. in northern India.