@article {96386, title = {First report of classical knockdown resistance (kdr) mutation, L1014F, in human head louse Pediculus humanus capitis (Phthiraptera: Anoplura)}, journal = {Medical and Veterinary Entomology}, volume = {37}, year = {2023}, pages = {209-212}, type = {Short communication}, abstract = {

There are at least three known knockdown resistance (kdr) mutations reported globally in the human head louse Pediculus humanus capitis De Geer (Phthiraptera: Anoplura) that are associated with reduced sensitivity to pyrethroids. However, the prevalence of kdr mutation in head lice is not known in the Indian subcontinent. To identify kdr mutations in the Indian head lice population, the genomic region of the voltage-gated sodium channel gene encompassing IIS1-2 linker to IIS6 segments was PCR-amplified and sequenced from P. humanus capitis samples collected from different geographic localities of India. DNA sequencing revealed the presence of four kdr mutations: M827I, T929I, L932F and L1014F. The presence of a classical kdr mutation L1014F, the most widely reported mutation across insect-taxa associated with the kdr-trait, is being reported for the first time in P. humanus capitis.

}, keywords = {Insecticide resistance, kdr mutation, Pediculosis, Pyrethroid, voltage-gated sodium channel.}, issn = {0269-283X, 1365-2915}, doi = {10.1111/mve.12596}, url = {https://resjournals.onlinelibrary.wiley.com/doi/abs/10.1111/mve.12596}, author = {Prashant K. Mallick and Ankita Sindhania and Toshi Gupta and Dhirendra P. Singh and Seema Saini and Singh,O. P.} } @article {95307, title = {First evidence of the mutations associated with pyrethroid resistance in head lice (Phthiraptera: Pediculidae) from Honduras}, journal = {Parasites \& Vectors}, volume = {13}, year = {2020}, month = {June-2020}, pages = {7 pp}, type = {Open Access}, abstract = {

Background:The human head louse, Pediculus humanus capitis, is a cosmopolitan blood-sucking ectoparasite affect-ing mostly schoolchildren in both developed and developing countries. In Honduras, chemical pediculicides are the first line of treatment, with permethrin as their main active ingredient. Despite the extended use of these products, there is currently no research investigating insecticide resistance in Honduran head lice. In head lice, the most com-mon mechanism is knockdown resistance (kdr), which is the result of two point mutations and the associated amino acid substitutions, T917I and L920F, within the voltage-sensitive sodium channel (VSSC).

Methods:Genomic DNA was extracted from 83 head lice collected in the localities of San Buenaventura and La Hicaca, Honduras. Polymerase chain reaction (PCR) was used to amplify a 332-bp fragment of the VSSC gene that contains a site affected by C/T mutation which results in a T917I amino acid substitution on each human head louse genomic DNA fragments.

Results:The C/T non-synonymous mutation which results in the T917I kdr amino acid substitution was detected in both head lice populations at frequencies ranging between 0.45\–0.5. Globally, the frequency of this substitution was 0.47. Of these, 5 (6.1\%) were homozygous susceptible and 78 (93.9\%) were heterozygotes. The kdr-resistant homozy-gote (RR) was not detected in the studied populations. Thus, 93.9\% of the head lice collected in Honduras harbored only one T917I allele. Exact test for the Hardy-Weinberg equilibrium for both localities showed that genotype frequen-cies differed significantly from expectation. In addition, San Buenaventura and La Hicaca populations had an inbreed-ing coefficient\  (Fis) \< 0, suggesting an excess of heterozygotes.

Conclusions:To our knowledge, this is the first study showing the presence of the C/T mutation responsible of the T917I kdr allele associated with pyrethroid resistance in P. h. capitis from Honduras. The PCR-restriction fragment length polymorphism (RFLP) employed here has demonstrated to be a reliable, economic, and reproducible assay that can be used to accurately genotype individual head lice for the mutation encoding the resistance-conferring T917I amino acid substitution. This highlights the necessity of proactive resistance management programmes designed to detect pyrethroid mutations before they become established within populations of head lice.

}, keywords = {Honduras, Insecticide resistance, kdr, Pyrethroid, Voltage-sensitive sodium channel}, doi = {10.1186/s13071-020-04183-2}, url = {https://parasitesandvectors.biomedcentral.com/articles/10.1186/s13071-020-04183-2}, author = {Kelsey Larkin and Carol Rodr{\'\i}guez and Shabana Jamani and Georgina Fronza and Gonzalo Roca-Acevedo and Ana Sanchez and Toloza,Ariel Ceferino} } @article {46569, title = {Susceptibility to DDT and some other insecticides of head lice (Pediculus capitis DeGeer) in Czechoslovakia}, journal = {Folia Parasitologica (Praha)}, volume = {31}, year = {1984}, note = {LR: 20041117; JID: 0065750; 0 (Insecticides); 50-29-3 (DDT); ppublish}, month = {1984}, pages = {169 - 175}, abstract = {For testing the susceptibility of the head louse to insecticides impregnated bunches of polyamide fibres, whose diameter resembled that of human hair (0.1 mm) were used. In this manner a low mortality of control lice collected from infected persons was obtained (2.9\% after 16 hours of exposure). Even after 25 years of DDT use no apparent resistance could be demonstrated in 25 tested louse populations and cross resistance to permethrin in 7 tested populations. The diagnostic concentration for resistance to pp{\textquoteright}-DDT was established at 1\%. Of the tested insecticides the highest toxicity was shown by malathion (LC50 = 0.000 018\%), pirimiphos-methyl had on average a twice lower toxicity, trichlorphon 104 times lower, tetramethrin 1220 times lower, permethrin 2.5 times lower and pp{\textquoteright}-DDT 630 times lower toxicity.}, keywords = {adolescent, animals, child, Child, Preschool, Comparative Study, Czechoslovakia, DDT, humans, insecticide, Insecticide resistance, Lice Infestations/parasitology, Pediculus, scalp}, isbn = {0015-5683}, author = {Rupes,V. and Ledvinka,J. and Chmela,J. and Pinterova,J.} } @article {46377, title = {Pediculus capitis pediculosis. Did a new type of louse appear?}, journal = {La Revue du praticien}, volume = {43}, year = {1993}, note = {LR: 20041117; JID: 0404334; ppublish}, month = {1993}, pages = {209 - 214}, address = {FRANCE}, keywords = {animals, child, Child, Preschool, humans, Insecticide resistance, Lice Infestations/drug therapy/epidemiology, Pediculus, scalp dermatoses}, isbn = {0035-2640}, author = {Richard-Lenoble,D.} } @article {46339, title = {Controlled study of malathion and d-phenothrin lotions for Pediculus humanus var capitis infested schoolchildren}, journal = {Lancet}, volume = {344}, year = {1994}, month = {1994}, pages = {1724 - 1727}, abstract = {

Anecdotal reports have suggested that reduced efficacy of pediculicides against Pediculus humanus capitis could be related to resistance to treatments. Ovicidal and pediculicidal activities of 0.5\% malathion and 0.3\% d-phenothrin lotions were tested in an experimental model of P humanus capitis grown on rabbits to ensure that the two treatments were pharmacologically equipotent. We then did a randomised controlled trial in which the lotions were administered to 193 P humanus capitis-infested schoolchildren (malathion, 95; d-phenothrin, 98). Success rate was defined as the absence of both live lice and viable nits. Before treatment, live lice were collected and subjected to a pediculicidal test. Pharmacological tests showed 100\% killing of the rabbit-grown nits and lice after exposure to both pediculicides. On day 1 of the controlled trial, the success rate was 92\% in the malathion group (95\% CI, 0.86-0.97) and 40\% in the d-phenothrin group (0.30-0.49) (p \< 0.0001); on day 7, it was 95\% in the malathion group (0.90-0.99) and 39\% in the d-phenothrin group (0.29-0.48, p \< 0.0001). Malathion was also significantly more active in the pediculicidal tests compared to d-phenothrin and control. These results suggest an acquired resistance to d-phenothrin in the schoolchildren tested, since all other conditions of the administration of insecticides were standardised.

}, keywords = {animals, child, Comparative Study, humans, Insecticide resistance, Lice Infestations/drug therapy, Malathion, Pediculus, Pyrethrum, Rabbit, Research Support, Non-U.S. Gov{\textquoteright}t, scalp dermatoses}, url = {http://www.phthiraptera.info/sites/phthiraptera.info/files/45219.pdf}, author = {Chosidow,Olivier and Chastang,C. and Brue,C. and Bouvet,E. and Izri,M. and Monteny,N. and Bastuji-Garin,S. and Rousset,J. J. and Revuz,J.} } @article {46246, title = {Laboratory studies of susceptibility and resistance to insecticides in Pediculus capitis (Anoplura; Pediculidae)}, journal = {Journal of Medical Entomology}, volume = {35}, year = {1998}, month = {1998}, pages = {814 - 817}, abstract = {

The susceptibility of local head lice to permethrin, sumithrin, deltamethrin, and carbaryl was determined by laboratory bioassays infield-collectedcolonies. Head lice collected from the infested heads of children 6-12 yr old were tested within 3 h of collection. The longest survival
of control insects in the laboratory was obtained by keeping them in the dark at 18\°C and 70 - 80\% RH. The base line susceptibility data obtained for insects collected from children not treated for lice, the reference colony, showed that deltamethrin caused the highest mortality of the insecticides tested (LC50, 0.06\%). Permethrin, sumithrin, and carbaryl showed no significant difference in mortality (superposition of confidence intervals), being 10 times lower than that caused by deltamethrin. All field-collected lice required a higher LC50 of permethrin than the reference colony. Resistance levels varied from 3 to \>100 for colonies that were taken from children treated with anti-lice products. Lice colonies with permethrin resistance showed resistance to sumithrin and deltamethrin, but resistance was not observed to the carbamate carbaryl.

}, keywords = {animals, Biological Assay, carbaryl, child, geography, humans, insecticide, Insecticide resistance, Lice Infestations/parasitology, Pediculus, Permethrin, Pyrethrum, Research Support, Non-U.S. Gov{\textquoteright}t}, isbn = {0022-2585}, url = {https://academic.oup.com/jme/article-pdf/35/5/814/18202141/jmedent35-0814.pdf}, author = {Picollo,Mar{\'\i}a In{\'e}s and Vassena,Claudia V. and Casadio,A. A. and Massimo,J. and Zerba,Eduardo Nicol{\'a}s} } @article {46245, title = {Treatment of Pediculus humanus var. capitis infestation in Cowlitz County, Washington, with ivermectin and the LiceMeister(R) comb}, journal = {Pediatric Infectious Disease Journal}, volume = {17}, year = {1998}, month = {1998}, pages = {923 - 924}, keywords = {adolescent, adult, animals, child, Child, Preschool, humans, insecticide, Insecticide resistance, Ivermectin/therapeutic use, Lice Infestations/drug therapy, Pediculus, Permethrin, Pyrethrum, scalp dermatoses, Washington}, author = {Bell,T. A.} } @article {46208, title = {Baseline susceptibility of a laboratory strain of Pediculus humanus humanus (Anoplura: Pediculidae) using a modified World Health Organization testing protocol}, journal = {Journal of Medical Entomology}, volume = {36}, year = {1999}, month = {1999}, pages = {903 - 905}, abstract = {The World Health Organization (WHO) protocol for determining resistance in body lice, Pediculus humanus humanus (L.), requires holding lice for long periods, which makes successful execution of the test difficult in field settings. The purpose of this study was to modify the WHO test procedure to make the holding period of lice shorter and the handling of lice easier. Susceptible lice from a laboratory colony were placed in a petri dish containing a paper that had been treated with an insecticide solution. After 6 h, the petri dish was turned on its side and lightly tapped on the table. Lice that were unable to cling to the paper were counted as knocked down. The KD50 in mg (AI)/ml of the insecticide solution used to treat the papers was as follows: lindane 0.060, permethrin 0.115, d-phenothrin 0.554, and malathion 1.008. If the diagnostic dose is set at 2 times the KD99, for this test procedure the diagnostic doses and WHO equivalent dose would be lindane, 0.368 mg (AI)/ml (WHO 0.132\%); permethrin, 0.498 mg (AI)/ml (WHO 0.206\%); d-phenothrin, 2.680 mg (AI)/ml (WHO 1.107\%); and malathion, 5.212 mg (AI)/ml (WHO 2.020\%).}, keywords = {animals, Animals, Laboratory, entomology, insecticide, Insecticide resistance, lindane, Malathion, Pediculus, Permethrin, Pyrethrum, World Health Organization}, url = {http://www.phthiraptera.info/sites/phthiraptera.info/files/45047.pdf}, author = {Zeichner,Brian C.} } @article {46175, title = {Resistance and the control of lice on humans and production animals}, journal = {International Journal for Parasitology}, volume = {30}, year = {2000}, month = {2000}, pages = {291 - 297}, abstract = {Phthiraptera (lice) are specialised insects adapted to parasitise many warm-blooded vertebrates, including domestic animals and humans. Often, attempts by the host to alleviate the irritation created by lice, causes derangement of the hair/fur coat. Unless treated, this derangement may cause economic losses due to hide damage and/or downgrading of wool/hair/fur. In 1981, application of aqueous insecticide solutions (dipping) for the control of sheep body lice (Bovicola ovis) was largely superseded by off-shears pyrethroid "pour-on" treatments. By 1985, several field failures with these products were found to be due to low-level (20x) insecticide resistance. In 1990, high-level (640x) resistance was diagnosed in a New South Wales population. However, despite 30+years use, organophosphate-based products are still usually effective. Until recently, cattle lice caused little concern. Treatments were applied mainly for aesthetic reasons when cattle were to be presented for sale, and also to prevent damage to fences by rubbing cattle. However, the introduction of quality-management programmes have raised awareness of the economic losses due to hide damage associated with lice infestations. Emerging industries such as emu and alpaca farming have raised the pest status of other louse species, and necessitated insecticidal intervention. In humans, attempts to control head lice, Pediculus humanus capitis, infestations have repeatedly failed around the world.}, keywords = {animals, Animals, Domestic, humans, insecticide, Insecticide resistance, Lice Infestations/prevention \& control/veterinary, organophosphate, Pediculus, plants, Pyrethrum, Research Support, Non-U.S. Gov{\textquoteright}t, sheep, Sheep Diseases/prevention \& control}, author = {Levot,G.} } @article {46136, title = {Persistent head lice following multiple treatments: evidence for insecticide resistance in Pediculus humanus capitis}, journal = {Australasian Journal of Dermatology}, volume = {41}, year = {2000}, note = {LR: 20041117; JID: 0135232; CIN: Australas J Dermatol. 2001 May;42(2):146. PMID: 11400694; CIN: Australas J Dermatol. 2002 May;43(2):154. PMID: 11982579; ppublish}, month = {2000}, pages = {250 - 254}, address = {AUSTRALIA}, abstract = {Viable head lice were found on the scalps of two family members following multiple topical insecticide treatments. The possibility of reinfestation had been reliably excluded. Persistent infestation could be diagnosed only after cutting the hair and combing repeatedly, which allowed visualization of juvenile (nymphal) and adult lice. Insecticide-resistant headlouse infestations are probably much more common than is generally realised and may persist unnoticed, so that more aggressive approaches will be needed to eradicate these ectoparasites from individuals and communities.}, keywords = {animals, Child, Preschool, Follow-Up Studies, humans, Infant, Insecticide resistance, Lice Infestations/diagnosis/therapy, Pediculus, Recurrence, scalp dermatoses}, isbn = {0004-8380}, author = {Bailey,Anita M. and Prociv,P.} } @article {46116, title = {Head lice resistance: itching that just won{\textquoteright}t stop}, journal = {Annals of Pharmacotherapy}, volume = {35}, year = {2001}, note = {LR: 20041117; JID: 9203131; 0 (Insecticides); ppublish}, month = {2001}, pages = {109 - 112}, address = {United States}, abstract = {OBJECTIVE: To evaluate the reports of resistance and cross-resistance to pediculicides in the head louse (Pediculus capitis), as well as the mechanisms involved. DATA SOURCES: Literature identified through a MEDLINE search (1966-April 2000) and through other secondary literature databases and/or bibliographies of pertinent articles. DATA SYNTHESIS: Head lice infestation is a common, worldwide problem. The widespread use of insecticide treatments together with inadequate treatment methods has led to a concern regarding the potential development of resistant head lice. This literature review examines the reports of resistance of the head louse as well as the purported mechanisms involved. CONCLUSIONS: Current research suggests that head lice resistance exists, but little is known regarding the actual incidence of this resistance or whether this incidence is increasing. More research is needed to assess the status of this problem. Proposed mechanisms for head lice resistance include knock-down resistance, glutathione S-transferase-based resistance, and monooxygenase-based resistance.}, keywords = {animals, humans, insecticide, Insecticide resistance, Lice Infestations/drug therapy/parasitology, Pediculus, Pruritus, scalp dermatoses}, isbn = {1060-0280}, author = {Bartels,C. L. and Peterson,K. E. and Taylor,K. L.} } @article {46065, title = {Comparative in vitro pediculicidal efficacy of treatments in a resistant head lice population in the United States}, journal = {Archives of Dermatology}, volume = {138}, year = {2002}, month = {2002}, pages = {220 - 224}, abstract = {

OBJECTIVE: To compare the pediculicidal activity of 5 head lice products available in the United States on head lice from south Florida.

DESIGN: In vitro pediculicidal product comparison.

SETTING: Lice Source Services, Inc, located in Plantation, Fla, a clinic for the treatment and grooming of individuals with pediculosis capitis.

PARTICIPANTS: Head lice were collected from healthy clients with Pediculus capitis that came to Lice Source Services, Inc, to seek their services.

INTERVENTIONS: Within 2 to 6 hours of capture, lice were placed in continuous direct contact with the pediculicide products and observed at regular intervals. Results were compared with findings of a recent study of a treatment-sensitive population of head lice conducted in Panama.

MAIN OUTCOME MEASURE: Percentage of lice dead at regular observation intervals between 5 minutes and 3 hours of continuous exposure to the pediculicides.

RESULTS: Two prescription products, Ovide lotion (0.5\% malathion) and 1\% lindane shampoo, were ranked in the same order as in 2 previous studies (first and last, respectively). The order of effectiveness from most to least effective was as follows: Ovide lotion, A-200 shampoo (a natural pyrethrin product synergized with piperonyl butoxide), undiluted Nix (1\% permethrin), diluted Nix, RID (a natural pyrethrin product synergized with piperonyl butoxide), and 1\% lindane shampoo.

CONCLUSIONS: There were statistically significant differences in the efficacy of all the products when compared with the results found in the recent study in Panama, except for Ovide lotion. Of those tested, Ovide was the only pediculicide in the United States that had not become less effective. The difference in efficacy of 1\% lindane, Nix, and pyrethrins between the Panama and Florida studies supports the argument that some head lice in the United States have become resistant to these treatments.

}, keywords = {adult, animals, child, Comparative Study, hair, humans, In Vitro, insecticide, Insecticide resistance, Kerosene, Lice Infestations/drug therapy, Lindane/pharmacology, Malathion, Pediculus, Piperonyl Butoxide, Pyrethrum, Research Support, Non-U.S. Gov{\textquoteright}t, scalp dermatoses}, doi = {10.1001/archderm.138.2.220}, url = {https://jamanetwork.com/journals/jamadermatology/fullarticle/478698}, author = {Meinking,Terri Lynn and Serrano,L. and Hard,B. and Entzel,P. and Lemard,G. and Rivera,E. and Villar,M. E.} } @article {46052, title = {Toxic effect of aliphatic alcohols against susceptible and permethrin-resistant Pediculus humanus capitis (Anoplura: Pediculidae)}, journal = {Journal of Medical Entomology}, volume = {39}, year = {2002}, month = {2002}, pages = {457 - 460}, abstract = {

The effectiveness of 1-octanol, 1-nonanol, 1-decanol, 1-undecanol, and 1-dodecanol was evaluated by immersion method against susceptible and permethrin-resistant head lice, Ped

}, keywords = {Alcohols/pharmacology, animals, Fatty Alcohols/pharmacology, Insect Control, Insecticide resistance, Octanols/pharmacology, Pediculus, Permethrin, Research Support, Non-U.S. Gov{\textquoteright}t, scalp dermatoses}, isbn = {0022-2585}, url = {https://academic.oup.com/jme/article/39/3/457/834975}, author = {Mougabure-Cueto,Gast{\'o}n A. and Paola Gonz{\'a}lez-Audino and Vassena,Claudia V. and Picollo,Mar{\'\i}a In{\'e}s and Zerba,Eduardo Nicol{\'a}s} } @article {45983, title = {Permethrin-resistant human head lice, Pediculus capitis, and their treatment}, journal = {Archives of Dermatology}, volume = {139}, year = {2003}, month = {2003}, pages = {994 - 1000}, abstract = {

OBJECTIVE: To compare the pediculicidal activity of Ovide lotion and its active ingredient, 0.5\% malathion, with Nix and its active ingredient, 1\% permethrin, in permethrin-resistant head lice. DESIGN: In vitro pediculicidal product and active ingredient comparison. The presence of knockdown resistance-type mutations (T929I and L932F) was validated by DNA sequencing. SETTING: University of Massachusetts-Amherst; University of Miami School of Medicine, Miami, Fla; Plantation and Homestead, Fla; and Mathis, Tex.Other PARTICIPANTS: Lice were collected in 3 geographical regions within the United States and in Yamburara, Ecuador, from healthy but infested individuals.Intervention Within 3 to 6 hours of collection, lice were given a blood meal, exposed to products or active ingredients, and observed at regular intervals. MAIN OUTCOME MEASURES: Percent mortality of lice at regular intervals after exposure to products or active ingredients and presence of T929I and L932F mutations. RESULTS: South Florida lice exhibited a significantly slower mortality response to permethrin compared with susceptible Ecuadorian lice. Ovide and malathion killed permethrin-resistant lice faster than Nix or permethrin. The presence of T929I and L932F in permethrin-resistant south Florida lice was confirmed by DNA sequencing. The population of Texas lice from Mathis was slightly resistant to permethrin and included 13\% with resistant genotypes. CONCLUSIONS: The presence of the T929I and L932F mutations was confirmed by DNA sequencing in lice collected from children in south Florida that were resistant to the pediculicidal effects of permethrin and the leading permethrin-based head lice product, Nix. Malathion resistance was not observed in this study. The data also show that Ovide killed these same permethrin-resistant head lice approximately 10 times faster than permethrin or Nix.

}, keywords = {animals, child, Comparative Study, Genotype, humans, In Vitro, insecticide, Insecticide resistance, Lice Infestations/drug therapy/genetics, Malathion, Pediculus, Permethrin, Research Support, Non-U.S. Gov{\textquoteright}t, Research Support, U.S. Gov{\textquoteright}t, P.H.S., scalp dermatoses, Time Factors}, url = {https://www.researchgate.net/publication/10609106_Permethrin-Resistant_Human_Head_Lice_Pediculus_capitis_and_Their_Treatment}, author = {Kyong Sup Yoon and Gao,Jian-Rong and Si Hyeock Lee and Clark,J. Marshall and Brown,Leon and Taplin,David} } @article {45871, title = {Increased monooxygenase activity associated with resistance to permethrin in Pediculus humanus capitis (Anoplura: Pediculidae) from Argentina}, journal = {Journal of Medical Entomology}, volume = {42}, year = {2005}, month = {2005}, pages = {342 - 345}, abstract = {

We studied the profile of permethrin resistance in populations of head lice infesting children 6-12 yr old in schools and their homes in and around Buenos Aires, Argentina. Fiv

}, keywords = {animals, Argentina, child, humans, Insecticide resistance, Pediculosis, Pediculus, Permethrin, Research Support, Non-U.S. Gov{\textquoteright}t}, url = {https://academic.oup.com/jme/article/42/3/342/849058}, author = {Paola Gonz{\'a}lez-Audino and Barrios,S. and Vassena,Claudia V. and Mougabure-Cueto,Gast{\'o}n A. and Zerba,Eduardo Nicol{\'a}s and Picollo,Mar{\'\i}a In{\'e}s} }