New techniques to collect live Sarcoptes scabiei and evaluation of methods as alternative diagnostics for infection.

Sarcoptes scabiei is a widespread, highly contagious skin disease that affects many mammals including humans. The biological characteristics of S. scabiei remain unclear. Therefore, the ability to collect adequate amount of mites for studies is required to advance our understanding of the parasite. The present study aimed to find a method to collect an adequate amount of live S. scabiei mites within a short time frame. The cornified layer and fur from an infected raccoon dog were inserted into a 50-ml catheter tip-type syringe. A 1.5-ml microtube was attached at the tip of the syringe to collect the mites, which crawled out from the cornified layer and fur. Four conditions were examined, and the following condition was determined to be the best: the syringe and microtube were shaded by aluminum foil, and the microtube was heated using a pet heater (36 °C). In addition, the effectiveness of this method as an alternative method to diagnose S. scabiei infections in animal was evaluated. S. scabiei live mites were not detected in the raccoon dog samples 24 h after the administration of medication (ivermectin or selamectin). The present study revealed that this technique was useful to collect adequate amounts of live mites, and the mites prefer a heated environment and actively move when using the shaded conditions. In addition, this technique was effective as an alternative diagnostic technique to detect live mites on an animal body.