title: Efficacy of plant essential oils for the repellents against chiggers (Leptotrombidium imphalum) vector of scrub typhus.
abstract: Scrub typhus caused by the Orientia tsutsugamushi. Rodents, particularly rats, serve as principal reservoir hosts. Infection in man is transmitted by the, chigger bite. Repellents provide an effective agent of protecting individuals from chigger. In the present study 6 plant essential oils were tested for evaluation of their repellent activity against the chigger, Leptotrombidium imphalum. The results showed that Clove oil was significantly more effective than others with ED50 and EC50 of 0.420 mg and 2.3%, followed by Zingiber oil (8.458 mg and 42.3%), Vetiver oil (19.582 mg and 97.9%), Turmeric oil (24.343 mg and 121.7%), Orange oil (27.310 mg and 136.6%) and Boesenbergia oil (30.486 mg and 152.4%). These results suggested that Clove oil was the most efficient repellent against chigger which is the vector for scrub typhus.
authors.affiliation: Armed Forces Research Institute of Medical Science, Royal Thai Amy, Bangkok, Thailand. ltwutti@hotmail.com
authors.forename: Wuttikon
authors.initials: W
authors.lastname: Rodkvamtook
authors.forename: Anchana
authors.initials: A
authors.lastname: Prasartvit
authors.forename: Chaiwat
authors.initials: C
authors.lastname: Jatisatienr
authors.forename: Araya
authors.initials: A
authors.lastname: Jatisatienr
authors.forename: Jariyanart
authors.initials: J
authors.lastname: Gaywee
authors.forename: Praphathip
authors.initials: P
authors.lastname: Eamsobhana
mesh_terms: D000818:Animals; D001096:Arachnid Vectors / Q000187:drug effects*; D007302:Insect Repellents / Q000494:pharmacology*; D007814:Larva / Q000187:drug effects; D008924:Mite Infestations / Q000517:prevention & control; D009822:Oils, Volatile / Q000494:pharmacology*; D010938:Plant Oils / Q000494:pharmacology*; D012612:Scrub Typhus / Q000517:prevention & control*; D014324:Trombiculidae
chemical_list: D007302:Insect Repellents; D009822:Oils, Volatile; D010938:Plant Oils