@article {95460, title = {Essential Oils as a Potential Treatment Option for Pediculosis}, journal = {Planta Medica}, volume = {86}, year = {2020}, month = {May-2020}, pages = {619-630}, type = {Epub}, abstract = {

Pediculosis is a prevalent ectoparasite infestation caused by lice. The head louse (Pediculus humanus capitis) and body louse (Pediculus humanus humanus) are obligatory parasites whose only known hosts are humans. Pediculosis is probably the most common ectoparasitic infestation, affecting up to 80\% of the population in several countries, and particularly prevalent in the infant population worldwide. Several treatment options, including shampoos and creams containing insecticides, have been introduced for the treatment of pediculosis. Recently, the use of synthetic chemicals to control human lice has raised concerns pertaining to human health and the environment. Therefore, increasing efforts have been undertaken to develop effective pediculicides with low environmental toxicity and minimal environmental residual activity. In this study, we focus on the essential oils derived from 22\ plant genera, their constituents, and the major factors that play important roles in the effectiveness of these oils in the treatment of pediculosis. Furthermore, we discuss the advantages and limitations of the mentioned essential oils, and ultimately suggest those demonstrating the most effective in vitro pediculicidal activities. The genera such as Aloysia, Cinnamomum, Eucalyptus, Eugenia, Lavandula, Melaleuca, Mentha, Myrcianthes, Origanum, Pimpinella, and Thymus appear to be more efficient against lice. These genera are rich in anethole, 1,8-cineole, cinnamaldehyde, p-cymene, eugenol, linalool, limonene, pulegone, terpinen-4-ol, and thymol compounds.

}, keywords = {eco-friendly pediculicides, Pediculosis, Treatment}, issn = {0032-0943, 1439-0221}, doi = {10.1055/a-1161-9189}, url = {https://www.thieme-connect.com/products/ejournals/abstract/10.1055/a-1161-9189}, author = {Kerdalidec Candy and Mohammad Akhoundi and Val{\'e}rie Andriantsoanirina and Durand,R{\'e}my and Bruel,Christiane and Izri,Arezki} } @article {95165, title = {Pediculicidal Activity Assessment of Four Essential Oil Terpenoids Using Filter Contact and Immersion Bioassays}, journal = {Jacobs Journal of Entomology and Zoological Studies}, volume = {2}, year = {2019}, month = {02-2019}, pages = {3 pp}, type = {Open Access, Research article}, abstract = {

Despite several reports of successful pediculicidal activity of essential oils, the role of their major components (terpenoids), attributed to be most effective molecules on head lice, are little known. Herein, we evaluated pediculicidal effectiveness of\  four\  terpenoids\  (linalool,\  geraniol,\β-caryophylleneandterpinen-4-ol) derived from most commonly used essential oils\  against\  head\  lice.\  Totally,\  300\  adult\  lice\  were\  collected\  from\  infested\  patients.\  Then\  for\  each\  evaluation\  method\  of\  filter contact and immersion, five series of 30 samples were examined separately using four terpenoids and sterile water as control. All samples affected by geraniol, linalool and terpinen-4-ol and 97\% of lice treated by \β-caryophyllene were dead at the end of immersion experiment. Geraniol and linalool were able to kill head lice on filter contact bioassay. Ter-pinen-4-ol and \β-caryophyllene were ineffective on 2 and 12 specimens respectively. Consequently, Geraniol, linalool and terpinen-4-ol demonstrated to be high effective in immersionand filter contact bioassays.

Also published as Letters to the Editor in 2020 see also https://phthiraptera.myspecies.info/node/95439

}, keywords = {Head lice; Terpenoids; Filter Contact; Immersion}, url = {https://jacobspublishers.com/uploads/article_pdf/54/scientific_54_732_25052019064730.pdf}, author = {Kerdalidec Candy and Mohammad Akhoundi and Bruel,Christiane and Izri,Arezki} } @article {94769, title = {Molecular Survey of Head and Body Lice, Pediculus humanus, in France}, journal = {Vector-Borne and Zoonotic Diseases}, volume = {18}, year = {2018}, month = {05-2018}, pages = {243 - 251}, abstract = {

Human lice, Pediculus humanus, are obligate blood-sucking parasites. Phylogenetically, they belong to several mitochondrial clades exhibiting some geographic differences. Currently, the body louse is the only recognized disease vector, with the head louse being proposed as an additional vector. In this article, we study the genetic diversity of head and body lice collected from Bobigny, a town located close to Paris (France), and look for louse-borne pathogens. By amplifying and sequencing the cytb gene, we confirmed the presence of clades A and B in France. Besides, by amplifying and sequencing both cytb and cox1 gene, we reported, for the first time, the presence of clade E, which has thus far only been found in lice from West Africa. DNA from Bartonella quintana was detected in 16.7\% of body lice from homeless individuals, but in none of the head lice collected from 47 families. Acinetobacter DNA was detected in 11.5\% of head lice belonging to all three clades and 29.1\% of body lice. Six species of Acinetobacter were identified, including two potential new ones. Acineto- bacter baumannii was the most prevalent, followed by Candidatus Acinetobacter Bobigny-1, Acinetobacter calcoaceticus, Acinetobacter nosocomialis, Acinetobacter junii, and Candidatus Acinetobacter Bobigny-2. Body lice were found to be infected only with A. baumannii. These findings show for the first time, the presence of clade E head lice in France. This study is also the first to report the presence of DNAs of several species of Acinetobacter in human head lice in France.

}, keywords = {Acinetobacter spp., bartonella quintana, clade E, France}, issn = {1530-3667}, doi = {10.1089/vbz.2017.2206}, url = {https://www.liebertpub.com/doi/10.1089/vbz.2017.2206}, author = {Kerdalidec Candy and Nadia Amanzougaghene and Izri,Arezki and Sophie Brun and Durand,R{\'e}my and Meriem Louni and Didier Raoult and Florence Fenollar and Oleg Mediannikov} } @article {94766, title = {In vitro efficacy of five essential oils against Pediculus humanus capitis}, journal = {Parasitology Research}, volume = {117}, year = {2018}, month = {02-2018}, pages = {603 - 609}, type = {Short communication}, abstract = {

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.

}, keywords = {bioassay, contact, Essential oils, filter paper, Head lce}, issn = {0932-0113}, doi = {10.1007/s00436-017-5722-5}, url = {http://link.springer.com/10.1007/s00436-017-5722-5}, author = {Kerdalidec Candy and Patrick Nicolas and Val{\'e}rie Andriantsoanirina and Izri,Arezki and Durand,R{\'e}my} } @article {94711, title = {Do drowning and anoxia kill head lice?}, journal = {Parasite}, volume = {25}, year = {2018}, month = { March 2018}, pages = {9 pp}, type = {Open Access}, abstract = {

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.

R\ésum\é - La noyade et l\’anoxie tuent-elles les poux de t\ête ? Des m\éthodes chimiques, physiques et m\écaniques sont utilis\ées pour contr\ôler les poux humains. Des tentatives ont \ét\é faites pour \éradiquer les poux de t\ête 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 \évalu\é le temps maximum que les poux de t\ête peuvent survivre \à l\’anoxie (privation d\’oxyg\ène) et leur capacit\é \à survivre \à une immersion prolong\ée dans l\’eau. Nous avons \également observ\é la p\én\étration de fluides \à travers les trach\ées des poux et les caract\éristiques du spiracle, contrastant avec celles d\écrites dans la litt\érature. Nous avons montr\é 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 \ét\é obtenu dans le groupe t\émoin non trait\é. Cependant, tous les poux sont morts apr\ès 16 h d\’anoxie. En revanche, le taux de survie des poux immerg\és \était significativement plus \élev\é que celui des poux non immerg\és apr\ès 6 h (100 \% contre 76,6 \%, p = 0,0037) et 24 h (50,9 \% contre 15,9 \%, p = 0,0003). Bien que les poux immerg\és dans l\’eau n\’aient pas ferm\é leurs spiracles, l\’eau n\’a pas p\én\étr\é dans le syst\ème respiratoire. En revanche, l\’immersion dans de la dim\éticone/cyclom\éthicone color\ée ou de l\’\éthanol color\é a entra\în\é une p\én\étration \à travers les spiracles et une propagation \à l\’ensemble du syst\ème respiratoire dans les 30 minutes, entra\înant la mort de 100 \% des poux.

}, keywords = {anoxia, drowning, oxygen, water}, doi = {10.1051/parasite/2018015}, url = {https://www.parasite-journal.org/10.1051/parasite/2018015}, author = {Kerdalidec Candy and Sophie Brun and Patrick Nicolas and Durand,R{\'e}my and Remi N. Charrel and Izri,Arezki} }