The effect of educational intervention on efficacy of 1% permethrin shampoo and 4% dimeticone lotion to treat head lice infestation using propensity score matching (PSM).

BACKGROUND: Head lice are a main public health problem and the most important human ectoparasites and the use of pediculicides is the most common way to control it. One of the possible causes of treatment failure is the lack of improper application of pediculicide. The aim of this study was to assess the effect of education on efficacy of 1% permethrin or 4% dimeticone lotion to treat head lice infestation. METHODS: This quasi-experimental study included 100 individuals with head lice infestation from comprehensive urban health centers in Ardabil as the intervention group, and 400 individuals from East Azerbaijan and West Azerbaijan provinces as the control group, from April to March 2019. The data collection tools included a demographic questionnaire and an examination recording sheet, which documented the presence of adult lice or nits. Due to the inability to perform random assignment and control for numerous observed covariates, propensity score matching (PSM) was used. RESULTS: The outcome of treatment included elimination of head lice infestation on is 7, and in the case of recurrence, it was considered on days 14 and 30 after treatment. The results showed that the educational intervention program had a significant positive effect on the efficacy of both treatments. The likelihood of improvement was approximately three times greater in the intervention group compared to the control group. CONCLUSION: Participants who received the training intervention (OR = 3.29; CI 95%: 2.21-4.88) were more likely to have a successful treatment than control group. In the case of providing proper training on the use of pediculicides and observing hygiene tips to patients with pediculosis, could help to successful treatment of pediculosis.

Pediculicide regulations and usage trends in Türkiye in 2015-2022.

BACKGROUND: Over the years, the increasing prevalence of head lice infestation has led to an increase in treatment-related costs and the development of resistance to pediculicides. This study aimed to evaluate pediculicide sales over an 8-year period (2015-2022), including the COVID-19 pandemic. METHODS: Data on products registered in the Turkish Pharmaceutical Index Dataview, Intercontinental Medical Statistics (IMS) database, sold on prescription and approved by the Ministry of Health in Türkiye were formally requested from the research organization IQVIA for pharmacologically active pediculicides (PAP) such as permethrin, pyrethrin, and sumithrin. Data for physically active products containing dimethicone (DMT) were obtained from the relevant pharmaceutical companies. Sale revenues were determined based on sale prices in the aforementioned year. RESULTS: Total sales of pediculicides decreased from 2,452,846 units in 2015 to 2,028,840 units in 2022. While PAP consumption decreased over the years, from 1,832,006 to 518,460 units, DMT consumption increased from 620,840 to 1,510,380 units, from 2015 to 2022. The total price of pediculicides for the consumer increased more than threefold in Turkish currency. In terms of USD, an almost similar amount of money was spent over the years, with the exception of 2022 when the expenditure almost halved mainly due to the high inflation rate in the country. CONCLUSION: The decrease in PAP and the increase in DMT indicate that local lice have developed resistance to the former. Further studies are needed to determine the possible development of resistance in the country.

Ovicidal and Pediculicidal Activity of Indigofera suffruticosa Mill. Leaf Oil on Pediculus humanus capitis Egg to Adult Stages.

PURPOSE: Pediculosis capitis, commonly known as head lice infestation, represents a significant health 26 problem for school children worldwide. Repeated and long-term usages of highly toxic pediculicides have resulted in the development of increased levels of resistance and do not kill louse eggs. Alternative pediculicides, such as herbal products, have recently been proposed for the treatment of head lice infestation, thereby decreasing toxicity. METHODS: This study analyzed the chemical composition of I. suffruticosa leaf extracts using GC-MS and evaluated the effects of Indigofera suffruticosa Mill. (I. suffruticosa) leaf extract on the mortality of head lice and their eggs. RESULTS: The major five components of the tested oils identified were as follows: n-hexadecanoic acid, hexadecanoic acid, ethyl ester, oleic acid, (E)-9-octadecenoic acid ethyl ester, and linoleic acid ethyl ester. The effective pediculicide of the I. suffruticosa leaf extracts affected head lice in all stages (egg, nymph, and adults). The concentrations of I. suffruticosa leaf extracts at 500 mg/mL produced the highest effective ovicidal on egg with 96.6% unhatching and pediculicide on nymphs and adults with 96.7 ± 5.7% and 86.7 ± 5.7% mortality, respectively, at 60 min (LT50 value < 10 min). The analysis of the external structure of the adult-stage head lice by SEM examination revealed that dead lice exposed to I. suffruticosa leaf extract displayed damage to the outer smooth architecture and obstructed the respiratory spiracles. CONCLUSION: We may conclude that the application of I. suffruticosa leaf extract produces an effective herbal pediculicide capable of affecting all stages of head lice.

Misleading Presentation of Unilateral Phthiriasis Palpebrarum in a 2-Year-Old Boy.

A 2-year-old boy with recently treated head lice presented with worsening right eyelid pruritus, irritation, and bleeding that was presumed to be a reinfection of head lice. Clinical examination revealed ectoparasites along the superior eyelid margin that were later identified as Phthirus pubis, or pubic lice. Treatment and management strategies are discussed. [J Pediatr Ophthalmol Strabismus. 2023;60(5):e55-e58.].

Effectiveness of a fixed-dose combination injectable (0.2 mg/kg doramectin + 6.0 mg/kg levamisole hydrochloride) against Rhipicephalus microplus and sucking lice infesting cattle.

Unmanaged tick and sucking lice infestations negatively impact the health and production potential of cattle. Described herein are two non-interference dose confirmation studies evaluating the efficacy of a single administration of a new fixed-dose combination injectable (FDCI) endectocide consisting of 0.2 mg/kg doramectin + 6.0 mg/kg levamisole hydrochloride, against either laboratory-induced Rhipicephalus microplus infestations in Australia or naturally acquired sucking lice (Linognathus vituli) infestations in the US. This FDCI is available as Dectomax V® in Australia and New Zealand and as Valcor® in the United States. To evaluate therapeutic efficacy against R. microplus, 12 calves were each exposed to 10 infestations of ∼5000 larvae per infestation between Days -24 and -2. Calves were either treated on Day 0 with the FDCI or left untreated (control). Additional R. microplus infestations of ∼5000 larvae were conducted on Day 2 and then three times weekly to also evaluate persistent efficacy of the FDCI. Tick collections were conducted daily from Day -3. Group mean live tick counts, egg production, and egg viability were analyzed for significant differences between the two groups. To determine efficacy of the FDCI against lice, 24 cattle with active sucking lice infestations based on Day -7 counts were allocated to two groups and treated on Day 0 with either saline (control) or the FDCI. Lice counts were conducted weekly from Day 14 through 42 and again on Day 56. Mean group lice counts on each count day were compared between treatment groups. In the R. microplus study presented here, cattle in Queensland, Australia treated with the FDCI (Dectomax V®) showed > 90 % reduction in tick counts based on arithmetic means within 48 h of treatment when compared to untreated cattle, and counts were > 95 % reduced from post-treatment Day 5 through Day 30. In the sucking lice study conducted in the US, the FDCI (Valcor®) displayed 100 % efficacy against sucking lice infestations (L. vituli) from first count day (Day 14 post-treatment) through Day 35 and then 99.9 % efficacy through Day 56 post-treatment. No treatment-related adverse events were reported for cattle in either study. Using R. microplus and sucking lice as representative ectoparasites, these studies demonstrate the ectoparasite activity of doramectin is retained in the new FDCI.

Clinical Characteristics and Prognosis of Pediatric Phthirus pubis Coinfestation of the Eyelashes and Scalp Hairs.

Phthirus pubis infestation is a highly infectious parasitic disease, affecting 1.3-4.6% of people globally. However, the coinfestation of P. pubis on the eyelashes and scalp hairs in children is uncommon, and the clinical characteristics and prognosis have not been fully studied. In this retrospective study, we report five pediatric patients diagnosed with eyelash and scalp coinfestation of P. pubis. The samples were obtained after treatment and sent for pathological examination. The demographic and clinical characteristics of the study participants were analyzed in detail. Numerous lice and nits were detectable on the eyelashes and scalp hairs in all enrolled patients. The ages ranged from 2 to 5 years. The duration of onset ranged from 3 to 10 days. The common clinical presentations were itching (100%) and conjunctivitis (60%). Treatment included eyelash and scalp hair trimming to the root (100%) and mechanical removal of the parasites (100%), in addition to topical tobramycin eye ointment (100%) and phenothrin shampoo (80%). Symptoms resolved by a 1-week follow-up. Pediatric P. pubis coinfestation mainly occurs on the eyelashes and temporal scalp in females, and sometimes contact tracing fails to identify the source. Phthirus pubis infestation of eyelashes can be misdiagnosed as blepharoconjunctivitis. Sexually transmitted diseases should be ruled out for patients with P. pubis infestation. Untreated or persistent cases may lead to several serious infections.

Comparative efficacy of chemical and botanical pediculicides in Thailand and 4% dimeticone against head louse, Pediculus humanus capitis.

Head louse infestations remain a global public-health concern due to increased resistance of lice to artificial pediculicides. In Thailand, there is a lack of comparative data on the current efficacy of pediculicides for treating head lice. In this study, we explored the status of botanical and toxic synthetic pediculicides with that of 4% dimeticone liquid gel for treating head lice in Thailand. The ex-vivo pediculicidal activity of various pediculicidal shampoos available at drugstores in Thailand was assessed and compared with that of 4% dimeticone liquid gel. The shampoos chosen were based on active ingredients toxic to lice (1% permethrin, 0.6% carbaryl, 0.15% Stemona root crude extract, or mixed plant extracts), whereas dimeticone acts physically on lice. We found that exposure to 4% dimeticone liquid gel following the manufacturer's instructions completely killed 100% of head lice in 15 min, whereas other pediculicide products failed to kill the great majority of head lice, whether treatment was for 10 min (resulting in 0% to 50.0% mortality) or 30 min (resulting in 17.0% to 60.0% mortality). We also extended a clinical assessment to confirm the efficacy of 1% permethrin for treating head lice in infested schoolchildren. In this clinical assessment, none of the 26 children treated with 1% permethrin shampoo achieved a cure after two applications. These results highlight that 4% dimeticone demonstrated a higher ex-vivo pediculicidal efficacy compared to both chemical and botanical pediculicides in Thailand. Conversely, 1% permethrin showed low efficacy in both laboratory and clinical assessments. Given its physical mode of action, 4% dimeticone merits consideration as an alternative treatment option for lice in Thailand, particularly in cases where treatment with toxic pediculicides has proven ineffective.

Over-the-counter Pediculus humanus capitis treatment: The nit comb is not appropriate for all hair types!

Biological diversity of hair affects what stress the hair can withstand. This proves to create a gap in care when evaluating over-the-counter (OTC) products available to treat Pediculus humanus capitis (head lice) in the United States. The nit comb would not be conducive for use in an individual with African hair, yet all OTC product instructions list the requirement of the nit comb. Lice treatment products provide instructions that are applicable for only specific hair types and do not address treatment recommendations for African hair. The OTC product instructions are outdated and exclusionary. A clear discrepancy and gap in care exist for many Americans seeking self-care treatment of pediculosis capitis. Pharmacists should remain aware of this discrepancy and counsel on alternative practices such as applying the active formulations in the hair but refrain from using the nit comb following the application of the topical medication.

Head lice: an inexpensive bioassay for use as guidance for healthcare workers monitoring treatment failures for insecticide resistance (1994-1999).

Head lice, Pediculus humanus capitis De Geer (Psocodea: Pediculidae) that failed to respond to pyrethroid insecticide-based treatment products were first identified in London and Cambridge, UK, in 1993 after which reports of treatment failure arose throughout the UK. There was a need amongst healthcare workers for a rapid detection method for resistance that could be used at the community level. A laboratory service was set up so that health professionals could send lice by overnight post for bioassay testing for resistance. In addition, test kits were provided so that testing could either be conducted on site or lice could be shipped to the laboratory on pre-treated test papers so that insecticide exposure could proceed while lice were in transit to the laboratory. Between 1994 and 1999, over 350 samples from 145 locations were tested and during this time populations of lice resistant to pyrethroids, malathion, and carbaryl were identified from all parts of the country, both urban and rural. In some areas, lice were only resistant to one of the insecticides available but in other places lice showed tolerance to all three insecticides used at the time.

Efficacy of a topical formulation containing esafoxolaner, eprinomectin and praziquantel (NexGard Combo®) against natural infestations with the cat louse, Felicola subrostratus under field conditions.

Felicola subrostratus is the only species of louse affecting domestic cats. Although it is considered a rare ectoparasite of pet cats, it occurs mainly in stray or shelter animals and is sometimes associated with intense pruritus and secondary bacterial infections. The aim of the present study was to evaluate the efficacy of a single dose of the topical formulation of esafoxolaner, eprinomectin and praziquantel (NexGard Combo®, Boehringer Ingelheim) in cats for the treatment of naturally acquired chewing lice infestation in a multi-site, positive-control, blinded clinical field study. Thirty-one domestic cats presenting natural F. subrostratus infestation were included in the study. The animals had not been treated with any ectoparasiticide within the previous 60 days. After inclusion, each cat was randomly assigned to one of the two groups: group 1, 14 cats treated with NexGard Combo® or group 2, 17 cats treated with Frontline Combo®. A clinical evaluation was performed at days 0 (inclusion), 14 and 30 and consisted in scoring the skin lesions and symptoms and scoring the presence of lice. On day 30, all cats from both groups scored 0 for the presence of live lice and no dead lice were found, demonstrating 100% efficacy. The clinical scores significantly improved from day 0 to day 30 in both groups. During the 30 days of surveillance, no reinfestations due to the hatching of eggs were observed and none of the cats had any adverse reactions. Esafoxolaner demonstrated high efficacy for the treatment of F. subrostratus infestation.

Title: Efficacité d'une formulation topique contenant de l'esafoxolaner, de l'éprinomectine et du praziquantel (NexGard Combo®) contre les infestations naturelles par le pou du chat, Felicola subrostratus, dans des conditions de terrain. Abstract: Felicola subrostratus est la seule espèce de pou affectant les chats domestiques. Bien que ce pou soit rare comme ectoparasite chez les chats de compagnie, il infeste principalement les animaux errants ou en refuge et est parfois associé à un prurit intense et à des infections bactériennes secondaires. Le but de la présente étude était d'évaluer l'efficacité d'une dose unique de la formulation topique d'esafoxolaner, d'éprinomectine et de praziquantel (NexGard Combo®, Boehringer Ingelheim) chez le chat pour le traitement de l'infestation naturelle par les poux broyeurs dans une étude de terrain multi-sites, randomisée, avec un contrôle positif. Trente et un chats domestiques présentant une infestation naturelle par F. subrostratus ont été inclus dans l'étude. Les animaux n'avaient été traités avec aucun ectoparasiticide au cours des 60 jours précédents. Après inclusion, chaque chat a été assigné au hasard à l'un des deux groupes : groupe 1, 14 chats traités avec NexGard Combo®, ou groupe 2, 17 chats traités avec Frontline Combo®. Une évaluation clinique a été réalisée aux jours 0 (inclusion), 14 et 30 et a consisté à un score clinique des lésions et symptômes cutanés et à noter la présence de poux. Au jour 30, tous les chats des deux groupes ont obtenu un score de 0 pour la présence de poux vivants et aucun pou mort n'a été trouvé, démontrant une efficacité de 100 %. Les scores cliniques se sont significativement améliorés du jour 0 au jour 30 dans les deux groupes. Au cours des 30 jours de surveillance, aucune réinfestation due à l'éclosion des œufs n'a été observée et aucun des chats n'a présenté d'effet indésirable. L'esafoxolaner a démontré une efficacité élevée pour le traitement de l'infestation par F. subrostratus.

Head Lice.

Head lice infestation is associated with limited morbidity but causes a high level of anxiety among caregivers of school-aged children and adolescents. Since the 2015 clinical report on head lice was published by the American Academy of Pediatrics, new medications have been approved, and an algorithm for management of affected patients is included. This revised clinical report clarifies current diagnosis and treatment protocols.

The Efficacy and Biopharmaceutical Properties of a Fixed-Dose Combination of Disulfiram and Benzyl Benzoate.

Scabies and hair lice are parasitic diseases that affect human skin and hair, respectively. The incidence and resistances of these infections are increasing. Tenutex® (disulfiram and benzyl benzoate emulsion) is an alternative to standard insecticides to avoid resistances. The aim of the work is to evaluate the transdermal absorption and the in vitro efficacy against scabies and hair lice after different exposition times. Dermatomed human skin was used to assess the dermal absorption using a validated High Performance Liquid Chromatography (HPLC) method. HEK001 keratinocytes were used to evaluate the cytotoxicity of benzyl benzoate. Only benzyl benzoate was able to cross the skin, but it did not show cytotoxicity at any of the tested concentrations. The product efficacy was tested on Psoroptes ovis after direct contact and after administration on sheep skin explants at different contact times. Permethrin/malathion-resistant strains of Pediculus humanis capitis adults and eggs were directly exposed to Tenutex, and the vitality and hatchability, respectively, were evaluated. The anti-scabies study demonstrated that exposure for 6 or 24 h completely eradicated the parasite. The pediculicidal activity of Tenutex exhibited superior efficacy than standard treatment on resistant lice. The positive results obtained suggest that Tenutex® is a good treatment option, especially in drug resistance situations.