02352nas a2200253 4500008004100000022001400041245008600055210006900141260001200210300001400222490000800236520161500244653001301859653001201872653001901884653001701903653001301920100002201933700002101955700003201976700001702008700001802025856005502043 2018 eng d a0932-011300aIn vitro efficacy of five essential oils against Pediculus humanus capitis0 aIn vitro efficacy of five essential oils against iPediculus huma c02-2018 a603 - 6090 v1173 a

Treatment of head lice has relied mainly on the use of topical insecticides. Today, conventional topical pediculicides have suffered considerable loss of activity worldwide. There is increasing interest in the use of natural products such as essential oils for head louse control, and many of them are now incorporated into various over-the-counter products presented as pediculicides, often without proper evaluation. The aim of the present study was to assess the in vitro efficacy of five essential oils against adults of Pediculus humanus capitis using a contact filter paper toxicity bioassay. The chemical composition of the essential oils from wild bergamot, clove, lavender, tea tree, and Yunnan verbena was analyzed by gas chromatography-mass spectrometry. All treatments and controls were replicated three times on separate occasions over a period of 11 months. In all, 1239 living lice were collected from the scalp of 51 subjects, aged from 1 to 69 years. Clove oil, diluted either in coco oil or sunflower oil, demonstrated the best adulticidal activity, reaching > 90% mortality within 2 h in lice submitted to a 30-min contact. Yunnan verbena oil diluted in coco oil showed also a significant efficacy. Other essential oils showed a lower efficacy. The oil’s major component(s) differed according to the tested oils and appeared chemically diverse. In the case of clove oil, the eugenol appeared as the main component. This study confirmed the potential interest of some of the essential oils tested, but not all, as products to include possibly in a pediculicidal formulation.

10abioassay10acontact10aEssential oils10afilter paper10aHead lce1 aCandy, Kerdalidec1 aNicolas, Patrick1 aAndriantsoanirina, Valérie1 aIzri, Arezki1 aDurand, Rémy uhttp://link.springer.com/10.1007/s00436-017-5722-504051nas a2200241 4500008004100000245004300041210004200084260001600126300000900142490000700151520342700158653001103585653001303596653001103609653001003620100002203630700001703652700002103669700001803690700002203708700001703730856006203747 2018 eng d00aDo drowning and anoxia kill head lice?0 aDo drowning and anoxia kill head lice c March 2018 a9 pp0 v253 a

Abstract - Chemical, physical, and mechanical methods are used to control human lice. Attempts have been made to eradicate head lice Pediculus humanus capitis by hot air, soaking in various fluids or asphyxiation using occlusive treatments. In this study, we assessed the maximum time that head lice can survive anoxia (oxygen deprivation) and their ability to survive prolonged water immersion. We also observed the ingress of fluids across louse tracheae and spiracle characteristics contrasting with those described in the literature. We showed that 100% of lice can withstand 8 h of anoxia and 12.2% survived 14 h of anoxia; survival was 48.9% in the untreated control group at 14 h. However, all lice had died following 16 h of anoxia. In contrast, the survival rate of water-immersed lice was significantly higher when compared with non-immersed lice after 6 h (100% vs. 76.6%, p = 0.0037), and 24 h (50.9% vs. 15.9%, p = 0.0003). Although water-immersed lice did not close their spiracles, water did not penetrate into the respiratory system. In contrast, immersion in colored dimeticone/ cyclomethicone or colored ethanol resulted in penetration through the spiracles and spreading to the entire respiratory system within 30 min, leading to death in 100% of the lice.

Résumé - La noyade et l’anoxie tuent-elles les poux de tête ? Des méthodes chimiques, physiques et mécaniques sont utilisées pour contrôler les poux humains. Des tentatives ont été faites pour éradiquer les poux de tête Pediculus humanus capitis par l’air chaud, en les trempant dans divers fluides ou en les asphyxiant à l’aide de traitements occlusifs. Dans cette étude, nous avons évalué le temps maximum que les poux de tête peuvent survivre à l’anoxie (privation d’oxygène) et leur capacité à survivre à une immersion prolongée dans l’eau. Nous avons également observé la pénétration de fluides à travers les trachées des poux et les caractéristiques du spiracle, contrastant avec celles décrites dans la littérature. Nous avons montré que 100 % des poux supportent 8 h d’anoxie et que 12,2 % survivent à 14 h d’anoxie ; 48,9 % de survie à 14h a été obtenu dans le groupe témoin non traité. Cependant, tous les poux sont morts après 16 h d’anoxie. En revanche, le taux de survie des poux immergés était significativement plus élevé que celui des poux non immergés après 6 h (100 % contre 76,6 %, p = 0,0037) et 24 h (50,9 % contre 15,9 %, p = 0,0003). Bien que les poux immergés dans l’eau n’aient pas fermé leurs spiracles, l’eau n’a pas pénétré dans le système respiratoire. En revanche, l’immersion dans de la diméticone/cyclométhicone colorée ou de l’éthanol coloré a entraîné une pénétration à travers les spiracles et une propagation à l’ensemble du système respiratoire dans les 30 minutes, entraînant la mort de 100 % des poux.

10aanoxia10adrowning10aoxygen10awater1 aCandy, Kerdalidec1 aBrun, Sophie1 aNicolas, Patrick1 aDurand, Rémy1 aCharrel, Remi, N.1 aIzri, Arezki uhttps://www.parasite-journal.org/10.1051/parasite/2018015