Prevalence of ocular demodicosis among patients at Tertiary Care Center,Bangkok,Thailand

AIM： To determine the prevalence of ocular demodicosis by both microscopic examination and molecular detection among patients at King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok.METHODS： One hundred individuals were enrolled in the study and were divided into five age groups. The meibomian gland dysfunction （MGD） score and qualities of cylindrical dandruff （CD） were also determined. Demodex mite infestations of eyelash samples were screened by both microscopic examination and semi-nested polymerase chain reaction （PCR）. RESULTS： The prevalence of ocular demodicosis as determined by microscopic examination was 42% [Demodex folliculorum （D. folliculorum） 41% and Demodex brevis （D. brevis） 1%]. Among patients who had ocular Demodex infestation, 69% have CD and had an average MGD score of 4; in patients without demodicosis, 15.5% had CD and had an average MGD score of 4.12. Prevalence of ocular demodicosis as determined by semi-nested PCR was 79% （D. folliculorum 78% and D. brevis 1%）.CONCLUSION： This is the first report on the prevalence of ocular demodicosis in Thailand. Patients with CD also had Demodex mites present. Semi-nested PCR is better than microscopy for Demodex infestation detection. An extensive survey with more representative samples is required to determine the prevalence in the country.

Efficacy of Once-Monthly Doses of Oral Afoxolaner and Afoxolaner/Milbemycin Oxime in a Well-Controlled Study for the Treatment of Canine Generalized Demodicosis

The efficacy of oral treatment with chewable tablets containing afoxolaner 2.27% w/w (NexGard?, Merial, now part of Boehringer-Ingelheim) or 1.875% w/w of afoxolaner and 0.375% w/w milbemycin oxime (NexGard Spectra?, Merial, now part of Boehringer-Ingelheim) was each assessed in eight dogs diagnosed with generalized demodicosis in this parallel group designed, blinded, randomized, single center negative controlled, efficacy study. Afoxolaner at the therapeutic dose (as close as possible to 2.5 mg/kg) was administered to Group 2 dogs, and afoxolaner (as close as possible to 2.5 mg/kg) with milbemycin oxime at 0.5 mg/kg was administered to Group 3 dogs on Days 0, 28 and 56. All dogs were observed once daily for general health starting on Day -7 until Day 84. All dogs were clinically examined on Days -7, -2, 14, 28, 42, 56, 70 and 84. Dogs were weighed on Days -7, -2, 27, 55, and 84. Live mite counts (based on five scrapings per dog and occasion) and clinical assessments, including photographic documentation, were performed on Days -2, 28, 56 and 84. Three monthly treatments with NexGard or NexGard Spectra against generalized demodicosis in dogs were highly effective resulting in a 99.9% and 100% efficacy against mites, respectively. After treatment with NexGard, only three live mites were recovered in five scrapings in one dog on Day 84. After treatment with NexGard Spectra, no mites were recovered in any scraping on any dogs in this group by Day 84. Both treatments resulted in a marked reduction of skin lesions and >90% hair-regrowth at three months after the initial treatment. Reduction of live mite counts was consistent with reduction in the extent and severity of the skin changes. Although the arithmetic mean mite numbers in the negative control group decreased slightly during the study, infection persisted in 7 of the 8 control dogs until Day 84. Both treatment groups of dogs showed a marked improvement of the associated dermatologic signs with steady improvement over the three-month treatment period.