Hyperplastic Dermatitis Associated with Acariasis in a Siamang (Symphalangus syndactylus)

Abstract

A 36-yr-old male captive siamang (Symphalangus syndactylus) was evaluated for mange in the form of generalized alopecia, flaky skin, and pruritus of 1 mo duration. Multiple skin scrapings and biopsies revealed high numbers of trombidiiform mites identified as Psorobia (formerly Psorergates) sp. near cercopitheci (Acarina: Psorergatidae) based on morphologic characteristics. Prolonged repetitive treatment with ivermectin killed the mites and resolved the clinical signs. Psorergatid mites should be considered as a cause of dry flaky skin in even long-term captive siamangs or other primates. This is the first record of psorergatid mites from a primate host in the family Hylobatidae.

Psorergatic mange in two ring‐tailed lemurs (Lemur catta)

“…Ivermectin was reported to be effective in one case, but mange relapsed 4 months after the end of treatment. 5 Moxidectin/imidacloprid spot-on and oral fluralaner were ineffective in the first case. Both macrocyclic lactones and fluralaner act on GABA and glutamate-gated chloride channels.…”

“…These molecules are very toxic, so the authors decided against their use. Ivermectin was reported to be effective in one case, but mange relapsed 4 months after the end of treatment 5 . Moxidectin/imidacloprid spot‐on and oral fluralaner were ineffective in the first case.…”

“…It was described in several wild-caught Cercopithecinae species and one siamang, and was caused by Psorobia cercopitheci or one Psorobia species akin to cercopitheci. [2][3][4][5] In these reports, facial and periorbital alopecia and scaly skin were the most common lesions. Nodules were rarely reported.…”

“…The siamang was housed with a female who never developed lesions. 5 Only few animals were infected in very large colonies of vervet monkeys. 2 It could be due to a long-term latency or a low-level presence of mites in these animals, which did not lead to clinical signs.…”

“…was suspected in the literature not to spread easily to conspecifics. The siamang was housed with a female who never developed lesions 5 . Only few animals were infected in very large colonies of vervet monkeys 2 .…”