Laboratory Evaluation of some Repellents Against Larval Trombiculid Mites1

Effectiveness of a Repellent Containing DEET and EBAAP for Preventing Tick Bites

“…In contrast, when Kulkarni and Naik 45 evaluated the effectiveness of DEET repellents under laboratory conditions against 6 species of ixodid ticks other than I ricinus , DEET (concentrations not reported), the effectiveness was between 80% and 100% against larval, nymphal, and adult ixodid ticks. In a field study, Schreck et al 43 found that a 1-minute application of pressurized sprays of permethrin at 0.5% and DEET at 20% and 30% to the exterior surface of pants and jackets provided 100%, 86%, and 92% protection against bites by all life stages of Ixodes scapularis .…”

“…[38][39][40][41] Several studies have indicated that it is also effective against ticks. [42][43][44][45] The other compound of interest in this study is ethyl-butylacetylaminopropionate (EBAAP). Its effectiveness against ticks has not been thoroughly investigated but appears to be similar to that of DEET.…”

“…Its effectiveness against ticks has not been thoroughly investigated but appears to be similar to that of DEET. 46 Most trials to evaluate the effectiveness of DEET have been either laboratory studies, 44,45 often with different tick species, or surveys conducted with small groups of volunteers. 42,43 No published data on the effectiveness of DEET and EBAAP for preventing tick bites by the European I ricinus could be found.…”

Development of an In Vitro Method for the Evaluation of Candidate Repellents AgainstLeptotrombidium(Acari: Trombiculidae) Chiggers

“…These data suggest that this procedure was extremely time-consuming. Buescher et al (1984), Kulkarni (1977) and Frances (1994) used a combination of repellent success and mortality effect to calculate median effective doses for a variety of candidate repellents. Although this method provided useful data, a minimum of 50 chiggers were required at each repellent concentration to obtain a valid estimate of the ED 50 .…”

“…A number of different methods have been used to assess repellent efÞcacy against chiggers (Madden et al 1944, Snyder and Morton 1946, Bertram et al 1967, Kulkarni 1977, Breeden et al 1982, Buescher et al 1984, Clopton and Gold 1992, Ho and Fauziah 1993, Frances 1994, Frances and Khlaimanee 1996, Tilak et al 2001. The most widely used method for the in vitro evaluation of repellents against chiggers is a modiÞcation of the median effective dose (ED 50 ) doseÐresponse system Þrst reported by Bertram et al (1967) and Kulkarni (1977). Limitations of this method are the large number of chiggers required and the amount of time (30 min) for each test.…”