Head lice

Head lice-induced anemia in a child and implications for oral health: Case report

Pediculosis capitis, colloquially referred to as head lice, engenders adverse social and economic consequences among children. While generally not considered a health hazard, chronic and severe head lice infestations have been linked to secondary iron-deficiency anemia. This case report documents a 7-year-old girl who presented for dental treatment with a history of social isolation and poor school attendance. Upon examination, the patient was found to have head lice and scabies infestations, resulting in secondary iron-deficiency anemia. The patient could return to full-time education after successful treatment for the head lice infestation administered by the dental team. This case underscores the need for treatment guidelines to manage children with diagnosed or suspected cases of head lice from a dental perspective. In instances of severe infestation, referral to a medical professional may be necessary for further management. This report highlights the importance of a multidisciplinary approach in managing head lice infestations and its implications on dental management.

Head lice infestation and the role of some cognitive-behavioral factors in its spread and prevention among adolescent girls: A cross-sectional study in Northwest Iran

Background and Aims

Head lice is a public health problem of worldwide distribution, particularly among school children and girls. Head lice infestation (HLI) can lead to negative social and psychological outcomes such as distress and anxiety in children and their families. Hence, the present study aimed to investigate the role of cognitive-behavioral factors in its spread and prevention among adolescent girls.

Methods

The cross-sectional study was conducted among 276 school-aged adolescent girls from September 2022 to January 2023 in Herris, a city located in Northwest Iran. A multistage cluster random sample was used to recruit adolescent girls in secondary schools. Two schools were randomly selected from five secondary schools. Then, students in each school were randomly selected from a school list. Data were collected using a valid and reliable questionnaire.

Results

The high protective behaviors were significantly associated with the number of family members (ß = 0.158; p value = 0.012). An additional 21.8% of the variation in preventive behaviors was explained by cognitive factors as predictor variables (p value > 0.05). Perceived collective family efficacy, perceived barriers, perceived self-efficacy, and response efficacy were predictors of head lice preventive behaviors, respectively. Among all variables, perceived collective family efficacy was the strongest predictor.

Conclusions

The findings of current research support the determinants of the cognitive-behavioral factors in the spread and prevention of HLI. It is better to involve these factors in school-based educational programs by policymakers and healthcare providers.

Prevalence of permethrin-resistant kdr mutation in head lice (Pediculus humanus capitis) from elementary school students in Jeddah, Saudi Arabia

Head lice (Pediculus humanus capitis) are a major global concern, and there is growing evidence of an increase in head lice prevalence among Saudi schoolchildren. The purpose of this study is to investigate the prevalence of an insecticidal resistance mutation in head lice collected from schoolchildren. A polymerase chain reaction (PCR) was used to amplify a segment of the voltage-gated sodium channel gene subunit to assess the prevalence and distribution of the kdr T917I mutation in head lice. Subsequently, the restriction fragment length polymorphism (RFLP) patterns revealed two genotypic forms: homozygous-susceptible (SS) and homozygous-resistant (RR). The results showed that 17 (37.80%) of the 45 samples were SS, whereas 28 (62.2%) were RR and T917I and L920F point mutations were found in the nucleotide and amino acid sequences of RR. Compared to other nations, the frequency of permethrin resistance mutation in the head louse population in Saudi Arabia was low. This study provides the first evidence of permethrin resistance mutation in human head lice in Saudi Arabia. The findings of this study will highlight the rising incidence of the kdr mutation in head lice in Saudi Arabia.

Pediculosis humanus capitis in 6-7 years old schoolchildren in Valencia, Spain

OBJECTIVES

Pediculosis humanus capitis is a worldwide public health concern that affects mostly school-aged children. The aim of this study is to determine the rate of pediculosis and to determine possible risk factors in a group of primary school children in Valencia, Spain; 227 children, 6-7 years old, were selected from 7 schools.

METHODS

A self-reported questionnaire completed by the parents/guardians about the presence of pediculosis in their children and their knowledge about pediculosis. The results recorded in the questionnaire were analysed by SPSS® software.

RESULTS

30.4% of the children had pediculosis. The results showed significant variation (p < 0.05) in prevalence depending on the following factors: sex, hair length, level of parental education, family size, presence of affected family member in the home, and frequency of hair washing. Less than half of parents/guardians showed an appropriate level of knowledge on pediculosis. Pediculosis remains a health problem in Valencian schoolchildren. The family size and existence of another member with pediculosis were shown to be the main potentiating factors.

CONCLUSIONS

Parents are not sufficiently informed about pediculosis and adopt inappropriate practices. There is a need to promote studies with the objective of determining risk factors for pediculosis as well as the need for actions to increase the knowledge of parents and healthcare professionals on this parasitosis to prevent outbreaks in the community, assure correct treatment and maintain effective epidemiological surveillance.

Comparative efficacy and safety of interventions for treating head lice: a protocol for systematic review and network meta-analysis

Background

Head lice infestation is a major public health problem around the globe. Its treatment is challenging due to product failures resulting from rapidly emerging resistance to existing treatments, incorrect treatment applications and misdiagnosis. Various head lice treatments with different mechanism of action have been developed and explored over the years, with limited report on systematic assessments of their efficacy and safety. This work aims to present a robust evidence summarising the interventions used in head lice.

Method

This is a systematic review and network meta-analysis which will be reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses statement for network meta-analyses. Selected databases, including PubMed, Embase, MEDLINE, Web of Science, CINAHL and Cochrane Central Register of Controlled Trials will be systematically searched for randomised controlled trials exploring head lice treatments. Searches will be limited to trials published in English from database inception till 2021. Grey literature will be identified through Open Grey, AHRQ, Grey Literature Report, Grey Matters, ClinicalTrials.gov, WHO International Clinical Trials Registry and International Standard Randomised Controlled Trials Number registry. Additional studies will be sought from reference lists of included studies. Study screening, selection, data extraction and assessment of methodological quality will be undertaken by two independent reviewers, with disagreements resolved via a third reviewer. The primary outcome measure is the relative risk of cure at 7 and 14 days postinitial treatment. Secondary outcome measures may include adverse drug events, ovicidal activity, treatment compliance and acceptability, and reinfestation. Information from direct and indirect evidence will be used to generate the effect sizes (relative risk) to compare the efficacy and safety of individual head lice treatments against a common comparator (placebo and/or permethrin). Risk of bias assessment will be undertaken by two independent reviewers using the Cochrane Risk of Bias tool and the certainty of evidence assessed using the Grading of Recommendations, Assessment, Development and Evaluations guideline for network meta-analysis. All quantitative analyses will be conducted using STATA V.16.

Discussion

The evidence generated from this systematic review and meta-analysis is intended for use in evidence-driven treatment of head lice infestations and will be instrumental in informing health professionals, public health practitioners and policy-makers.

PROSPERO registration number

CRD42017073375.

Treatment of Head Louse Infestation with a Novel Mixture Made of Semi-Crystalline Polymers and Plant Extracts: Blind, Randomized, Controlled, Superiority Trial

The rate of head louse infestations is increasing. Most of the neurotoxic treatments are not reliably ovicidal and are faced with genetic resistance. The treatments based on a mechanical mode of action show no sufficient efficacy, transferring the chances of a cure on a tedious combing or leaving the hair fatty. This double-blinded, randomized, controlled, superiority trial evaluates the efficacy and safety of a novel mixture made of semi-crystalline polymers and plant extracts. Forty-five participants received a single application of either 1% Permethrin lotion or the novel lotion, applied for 15 minutes. Untreated and treated nits were collected and placed in an incubator during 10 days. The worst case intent-to-treat analysis found the novel lotion significantly more effective than 1% Permethrin, with 21/22 (95.5%) participants cured and 9/23 (39.1%), respectively (p < 0.0001). Rate of viable nymphs was 0.5 (2.1) for the new lotion and 40.8 (20.4) for the 1% Permethrin. The new lotion cures head louse infestations, offering an effective alternative treatment, with a high efficacy for inhibiting the hatching of eggs. Its physical actions on lice and their eggs should not be affected by resistance to neurotoxic insecticides.

Key Potentially Inappropriate Drugs in Pediatrics: The KIDs List

OBJECTIVES

The safe use of medications in pediatric patients requires practitioners to consider the unique pharmacokinetics and pharmacodynamics of drugs prescribed in this age group. In an effort to create a standard of care for the safe use of medications in this population, a list of drugs that are potentially inappropriate for use in pediatric patients has been developed and titled the "KIDs List."

METHODS

A panel of 7 pediatric pharmacists from the Pediatric Pharmacy Association were recruited to evaluate primary, secondary, and tertiary literature; FDA Pediatric Safety Communications; the Lexicomp electronic database; and product information for drugs that should be considered potentially inappropriate for use in pediatric patients. Information was rated using predefined criteria. A PubMed search was conducted using the following terms: adverse drug events OR adverse drug reactions. The search was limited to humans; age <18 years; case reports, observational studies, or clinical trials; and English language. No date range was used. Results were used to create an evidence-based list of candidate drugs that was then peer-reviewed and subjected to a 30-day public comment period prior to being finalized.

RESULTS

A PubMed search yielded 4049 unique titles, of which 210 were deemed relevant for full review. Practitioner recommendations highlighted an additional 77 drugs. FDA Pediatric Safety Communications and the Lexicomp database yielded 22 and 619 drugs, respectively. After critical analysis, peer review, and public review the final KIDs List contains 67 drugs and/or drug classes and 10 excipients.

CONCLUSIONS

This extensive effort led to compilation of the first list of drugs that are potentially inappropriate for prescribing in all or in a select subgroup of pediatric patients. If avoidance is not clinically possible, the drug should be used with caution and accompanied by appropriate monitoring.

Vaccuuming method as a successful strategy in the diagnosis of active infestation by Pediculus humanus capitis

Most human epidemiological and clinical studies use visual inspection of the hair and scalp to diagnose Pediculus humanus capitis , however this method has low sensitivity to diagnose active infestations (presence of nymphs and adult lice). Vacuuming the hair and scalp has been used as a diagnostic method, but there are no previous data comparing its effectiveness with visual inspection. The aim of this study was to determine the prevalence of overall infestation (nits and trophic stages), of active infestation by Pediculus humanus capitis , and to evaluate the effectiveness of vacuuming in comparison with the visual inspection. Visual inspection was performed by three examiners and vacuuming of the scalp by one investigator, with an adapted vacuum cleaner. A total of 166 children aged 4 to 10 years old were randomly selected from public schools in Southern Brazil. Considering the positive results obtained by both methods, the prevalence of overall infestation was 63.3%, whereas active infestation was 18.7%. The visual inspection was more effective on diagnosing overall infestation, however, its effectiveness to detect active infestation was lower, ranging from 0.6% (RR=3%, p<0.001) to 6.6% (RR=35%, p=0.001), depending on the number of examiners. The effectiveness of vacuuming to diagnose active infestation was higher than the one of visual inspection, with a prevalence rate of 16.3% (RR=87%, p=0.332). As presented in our study, the vacuuming method was 2.74 to 7.87 times most likely to detect active infestation, thus it could be adopted as a more accurate method to diagnose active pediculosis.

Cognitive Factors Associated to Pediculosis Preventive Behaviors Among Mothers of School-Age Children in Chaldoran County, Iran

BACKGROUND

Despite the improvement of living standards and public health as well as conducting the specific programs based on pediculosis control guidelines, Head Lice Infestation (HLI) is still a worldwide health concern. The purpose of this study was to investigate the cognitive factors associated to school-age children's HLI among mothers in an urban community.

SUBJECTS AND METHODS

In this cross-sectional study, a multi-stage cluster random sample of 619 mothers of students in elementary schools of Chaldoran County, located in North-West of Iran, was recruited to participate in the study. Data were collected applying a set of questionnaires including socio-demographic and cognitive-behavioral factors, including Pediculosis Preventive Behaviors (PPBs), HLI knowledge, threat appraisal, as well as HLI prevention perceived self-efficacy, response efficacy, and perceived collective family efficacy.

RESULTS

Statistically significant differences were found in the children's HLI by their mother's age and performance in PPBs (p-value=0.001). Hierarchical multiple linear regressions were performed with PPBs as outcome variable. According to their natures, the predictors for this outcome variable were classified in two different blocks. Demographic characteristics (p > 0.05), and cognitive constructs (p< 0.001) explained 9% and 21.1% of the observed variance in PPBs, respectively. Pediculosis was found as an epidemic among the students, particularly female students, of Chaldoran County, which call for action by health stakeholders and policymakers.

CONCLUSION

The healthcare providers are recommended to develop HLI prevention programs, within which the mothers and their school-age children as well as school mangers and public places' employers are considered as the core target groups for interventions. Besides PPBs, response efficacy and perceived collective family efficacy to perform the behaviors should be considered as the core categories while designing such prevention programs.

Stigma resulting from head lice infestation: A concept analysis and implications for public health

AIM

The aim of this concept analysis was to examine stigma in the context of head lice, illuminating its components and providing insights for the development of appropriate nursing interventions.

BACKGROUND

Stigma associated with the phenomenon of head lice management is pervasive, promulgating fear and influencing policy and treatment practices. Few studies have examined stigma in this context.

METHOD

The method followed was the Rodgers's evolutionary method.

DATA SOURCES

Health, education, and social sciences databases were searched and yielded 20 articles spanning 1996-2018 used to create a relevant literature review.

RESULTS

Stigma arising from head lice infestation is preceded by an actual or perceived case of head lice, negative perceptions of lice, negative perception of groups or persons with head lice, or being associated with a group or person of lesser status believed to be a carrier of head lice. Defining attributes include marks of infestation, negative and unfair beliefs, and shame. Consequences of stigma are economic costs, social costs, mistreatment, and overtreatment with pediculicides.

CONCLUSION

The concept of stigma in the context of head lice management is multifaceted. Further research is required to understand the magnitude of stigma as well as other factors associated with optimal treatment of children with head lice.

Toxicokinetics of cis- and trans-Permethrin: Influence of Isomer, Maturation, and Sex

Permethrin exposure of children and adults is widespread in many populations, but knowledge of its relative toxicokinetics (TK) and health risks in immature age groups is lacking. Studies were conducted in rats to determine the influence of immaturity and sex (on plasma and target organ dosimetry of each of the insecticide’s 2 isomers, cis- and trans-permethrin [CIS and TRANS]). Postnatal day 15, 21, and 90 (adult), Sprague Dawley rats were orally administered a graduated series of doses of CIS and TRANS in corn oil. Serial sacrifices were conducted over 24 h to obtain plasma, brain, liver, skeletal muscle, and fat profiles of CIS and TRANS. Levels of TRANS decreased relatively rapidly, despite administration of relatively high doses. Concentrations of each isomer in plasma, brain, and other tissues monitored were inversely proportional to the animals’ age. The youngest pups exhibited 4-fold higher plasma and brain area under the curves than did adults. Little difference was observed in the TK of CIS or TRANS between adult male and female rats, other than higher initial plasma and liver CIS levels in females. Elevated exposure of the immature brain appears to be instrumental in increased susceptibility to the acute neurotoxicity of high-dose permethrin (Cantalamessa [1993]), but it remains to be established whether age-dependent TK is relevant to long-term, low-level risks.

Severe pediculosis capitis in a nursery school girl

La pediculosis capitis es la ectoparasitosis más frecuente a nivel mundial. La infestación es causada por Pediculus humanus capitis (piojo de la cabeza) y afecta el cabello, el cuero cabelludo y la piel. Rara vez se manifiesta con otro tipo de sintomatología y, por lo general, su curso es benigno si se trata adecuadamente.

Se presenta el caso de una menor con pediculosis capitis de 18 meses de evolución, asociada con forúnculos, lesiones cutáneas, múltiples adenopatías y anemia, que no mejoró tras la aplicación del champú.

Inicialmente, llamó la atención la presencia de forúnculos, alopecia y adenopatías. La persistencia de la pediculosis capitis y el rascado intenso alteraron la integridad de la epidermis y facilitaron las infecciones secundarias por bacterias patógenas y oportunistas que produjeron impétigo, forunculosis, excoriaciones, costras hemáticas, anemia, alopecia y linfadenopatías. La pediculosis capitis afectó notoriamente a la paciente al causarle problemas psicológicos y de salud, agudizados por su condición económica y social. La paciente presentó manifestaciones clínicas poco frecuentes (forunculosis, anemia, fiebre, alopecia y adenopatías), lo cual se vio facilitado por la persistencia de los factores de riesgo y el hecho de que no se le inspeccionaba la cabeza ni se removían los insectos. La educación sobre los factores de riesgo y el control sanitario es indispensable para controlar la infestación.

Toxicokinetics of Deltamethrin: Dosage Dependency, Vehicle Effects, and Low-Dose Age-Equivalent Dosimetry in Rats

There is increasing concern that infants and children may be at increased risk of neurological effects of pyrethroids, the most widely used class of insecticide. The objectives of this investigation were to (1) characterize the dose-dependent toxicokinetics (TK) of deltamethrin (DLM) for exposures ranging from environmentally relevant to acutely toxic; (2) determine the influence of an aqueous versus oil vehicle on oral absorption and bioavailability; and (3) determine whether DLM exhibits low-dose, age-equivalent internal dosimetry. Serial arterial plasma samples were obtained for 72 h from adult, male Sprague Dawley rats given 0.05-5.0 mg DLM/kg as an oral bolus in corn oil (CO). DLM exhibited linear, absorption rate-limited TK. Increases in maximum plasma concentration (Cmax) and AUC∘∞ were directly proportional to the dose. Oral bioavailability was quite limited. The vehicle and its volume had modest effect on the rate and extent of systemic absorption in adult rats. Postnatal day (PND) 15, 21, and 90 (adult) rats received 0.10, 0.25, or 0.50 mg DLM/kg orally in CO and were sacrificed periodically for plasma, brain, and liver collection. Age-dependent differences between PND 15 and 90 plasma Cmax and AUC∘24 values progressively diminished as the dose decreased, but there was a lack of low dose age equivalence in these brain and liver dosimeters. Other maturational factors may account for the lack of the low-dose age equivalence in brain and liver. This investigation provides support for the premise that the relatively low metabolic capacity of immature subjects may be adequate to effectively eliminate trace amounts of DLM and other pyrethroids from the plasma.

Lice Update: Management and Treatment in the Home

Lice infestation is a common health issue affecting 6 to 12 million school-age children in the United States each year, impacting all members of the household. The home care nurse can be a valuable resource in the management of lice in the home and can assist the family in understanding the various myths and misconceptions about lice. This article provides an overview of lice management, including identification and treatment of a lice infestation as well as recommendations for environmental control strategies in the home. It includes an overview of the various over-the-counter and prescription treatment options and highlights the social stigma that is often associated with a lice infestation.

Ovicidal effect of essential oils from Zingiberaceae plants and Eucalytus globulus on eggs of head lice, Pediculus humanus capitis De Geer

BACKGROUND

Head lice infestation is an important public health problem worldwide. Chemical pediculicides have lost their efficacy because lice have developed resistance to them. Therefore, alternative pediculicides such as essential oils and herbal products have been proposed for treating head lice infestation.

STUDY DESIGN

To determine the efficacy of essential oils from three Zingiberaceae plants (Curcuma xanthorrhiza, Curcuma zedoaria and Zingiber zerumbet) against head lice eggs and to investigate an augmenting substance (Eucalyptus globulus EO) for improving the efficacy of these essential oils in killing head lice eggs, especially on the inhibition of their hatching process. Permethrin pediculicide, soyabean oil, and drinking water were used as positive, negative, and neutral controls, respectively.

METHODS

An immersion test was used to evaluate the ovicidal activity of 12 essential oil formulations. Head lice eggs were immersed for 1, 5 and 10 min in the treatments. Mortality rate was observed on day 7 and day 14; mortality was checked under a stereomicroscope.

RESULTS

All head lice eggs that were immersed in a combination of 10% C. zedoaria EO and 10% E. globulus EO for 5 min did not hatch at all for 7-14 days of incubation. All head lice eggs that were immersed in soyabean oil and drinking water for 1, 5, and 10 min showed 100% hatching rate in 7-14 days of incubation. All head lice eggs that were immersed in permethrin pediculicide for 1, 5 min, showed 100% hatching rate, but when they were immersed for 10 min, permethrin provided 4.0-6.0% inhibition rate with 94.0-96.0% hatching rate for 7-14 days of incubation. All combinations of Zingiberaceae EOs and E. globulus EO at low and high concentrations (5 and 10%) exhibited high ovicidal activities against head lice eggs, and the combinations showed a synergistic effect with an increase in the inhibition rate of more than 50%.

CONCLUSION

These results demonstrated that Zingiberaceae EOs augmented with E. globulus EO are promising ovicidal agents for head lice control.

Effect of a health education program on reduction of pediculosis in school girls at Amphoe Muang, Khon Kaen Province, Thailand

BACKGROUND

Pediculosis caused by head lice (Pediculus humanus capitis) infestation is still an important health problem in schoolchildren, especially girls, worldwide, including in Thailand. Although pediculicidal agents effectively kill head lice, the re-infestation rate is still high. Thus, prevention is an important strategy for any sustainable control program. We aimed to develop and evaluate the efficacy of a health education program for increasing knowledge, changing attitudes and promoting preventive practices to reduce prevalence of pediculosis among school girls in Amphoe Muang, Khon Kaen, northeastern Thailand.

METHODOLOGY

Six schools were selected using multistage simple randomization and were allocated into intervention or control groups. A total of 267 girls was enrolled from these schools. A "knowledge, attitude and practice" (KAP) questionnaire, consent forms and health education materials were constructed and tested by experts and in one pilot school before the main investigation. Baseline prevalence of adult lice and nits was determined. The health education package was given only to the intervention group. The KAP questionnaire was re-evaluated at two months after intervention.

RESULTS

At baseline, the prevalence and intensity of head lice infestation, and the KAP scores did not differ significantly between the two groups. After re-evaluation at two months, the KAP score was significantly greater in the intervention group. A significant decrease of the infestation rate from 59% to 44% was observed in the intervention group, whereas infestation increased in the control group (from 56% to 65%). The incidence of new cases in the intervention group (6.14%) was lower than in the control group (12.62%).

CONCLUSION

These findings indicated that the newly-established health education package is an effective tool for increasing KAP and reducing head lice infestation in school girls. Efforts to combat pediculosis in schoolchildren elsewhere may consider including this, or a similar, health education package in their programs.

Human head lice and pubic lice reveal the presence of several Acinetobacter species in Algiers, Algeria

There are two majorspecies of medically important lice that parasitize humans: Phthirus pubis, found in pubic hair, and Pediculus humanus. Pediculus humanus consists of two eco types that live in specific niches on the human host: body lice (Pediculus humanus humanus), found on the human body and clothing, and head lice (Pediculus humanus capitis), found on the scalp. To date, only body lice are known to be vectors of human disease; however, it has recently been reported that the DNA of several bacterial agents has been detected in head lice, raising questions about their role in the transmission of pathogens. This issue caught our attention, in addition to the fact that the pathogenic bacteria associated with P. pubis and P. humanus capitis have never been investigated in Algeria. To investigate this,molecular techniques (real-time PCR) were used to screen for the presence of Acinetobacter spp., Bartonella spp., Borrelia spp. and Rickettsia prowazekii DNA from P. humanus capitis (64 lice) collected from schoolchildren,and P. pubis (4 lice),collected from one adultman living in Algiers. Positive samples for Acinetobacter spp.were identified by sequencing therpoBgene. Conventional PCR targeting the partial Cytb gene was used to determine the phylogenetic clade of the collected lice. Of the 64 samples collected, Acinetobacter spp. DNA was detected in 17/64 (27%) of head lice, identified as: A. baumannii (14%), A. johnsonii (11%) and A. variabilis (2%). Of the four P. pubissamples, 2(50%) were positive for A. johnsonii. The phylogenetic tree based on the Cytb gene revealed that P. humanus capitis were grouped into clades A and B. In this study, we report andidentify for the first time Acinetobacter spp.in Algerian P. pubis and P. humanus capitis. The detection of the genus Acinetobacter in lice should not be underestimated, especially in P. humanus capitis, which is distributed worldwide. However, additional epidemiological data are required to determine if human lice may act as an environmental reservoir and are actively involved in the propagation of these bacteria to humans.

Ovicidal Efficacy of Abametapir Against Eggs of Human Head and Body Lice (Anoplura: Pediculidae)

Studies were undertaken to determine the ovicidal efficacy of 5,5'-dimethyl-2,2'-bipyridyl (abametapir) against eggs of both human head and body lice. Head lice eggs of different ages (0-2, 3-5, and 6-8-d-old eggs) were exposed to varying concentrations of abametapir in isopropanol and concentration-dependent response relationships established based on egg hatch. One hundred percent of all abametapir-treated eggs failed to hatch at the 0.74 and 0.55% concentrations, whereas 100% of 6-8-d-old head louse eggs failed to hatch only at the 0.74% concentration. The LC₅₀ value for abametapir varied, depending on the age of the head lice eggs, from ∼0.10% recorded for 0-2-d-old eggs and increasing to ∼0.15% for 6-8-d-old eggs. Abametapir was also evaluated once formulated into a lotion referred to as Xeglyze (0.74% abametapir) and serial dilutions made. Ovicidal efficacies were determined against head lice eggs 0-8-d-old. Results indicated 100% ovicidal activity at the 0.74, 0.55, 0.37, and 0.18% concentrations. Additional studies undertaken using body lice eggs also demonstrated that abametapir was 100% ovicidal against eggs of all ages when evaluated at a concentration of 0.37 and 0.55%. Given that ovicidal activity is a critical component of any effective treatment regime for louse control, the data presented in this study clearly demonstrate the ability of abametapir to inhibit hatching of both head and body louse eggs as assessed in vitro.

A Lousy Reason for Surgery Cancellations

Cancellation of surgery has significant adverse impact on patients, health care providers, and their associated facilities. Although head lice infestation has not been shown to be associated with adverse surgical outcomes, it often prompts case cancellation by surgical and anesthesia personnel. The purpose of our study was to evaluate the extent and impact of surgery cancellations due to head lice infestation. In our study, a total of 9 patients were cancelled over a 3-year period. Although there is no direct evidence to show that head lice infestation poses a risk to surgical outcomes, the possibility of underlying secondary bacterial infection at the skin excoriation site is often the concern in these patients. This study offers the first investigation into the impact of head lice infections on operating room cancellations, which may prove to be a potential source of intervention to prevent cancellations.

Efficacy and Safety of a Mineral Oil-Based Head Lice Shampoo: A Randomized, Controlled, Investigator-Blinded, Comparative Study

BACKGROUND

Due to increased resistance and safety concerns with insecticide-based pediculicides, there is growing demand for head lice treatments with a physical mode of action. Certain mineral oils kill lice by blocking spiracles or by disrupting the epicuticular wax layer. The present study was performed to evaluate efficacy and safety of a mineral oil-based shampoo.

METHODS

This randomized, controlled, investigator-blinded, monocentric study (EudraCT registration no. 2014-002918-23) was performed from October 2014-June 2015 in Germany. A mineral oil shampoo (Mosquito® Med Läuse Shampoo 10 in Germany, Paranix or Silcap shampoo elsewhere), registered as medical device, was compared to a conventional, locally reimbursed, pyrethroid-based pediculicide (Goldgeist® Forte solution). In total, 107 patients (>1 year) with confirmed head lice infestation were included (test arm: n = 53; control arm: n = 54). All subjects received two applications of either test or control product at day 0 and day 7, according to the instructions for use. Efficacy and safety was evaluated directly, 1h and 24h after first application, before and after second treatment, and at day 10. The main objective was demonstrating a cure rate for the test product, being superior to 70% at day 10.

RESULTS

Cure rates at day 10 (corrected for re-infestation) for the test product (96.1%) and control (94%) significantly exceeded the pre-defined target (70%) (p < 0.001, 2-sided, 1-sample, chi-square test) with confirmed non-inferiority for the test product. Over all visits, cure rates were consistently higher for the test product, whereas more initially-cured subjects remained lice-free until end of study (78%; control: 60%). Both products were safe and well tolerated, offering good esthetical effects.

CONCLUSION

This study showed that substance-based medical devices (including the tested mineral oil shampoo) can be safe and effective alternatives for insecticide-based pediculicides, with less risk for development of resistance because of the physical mode of action.

TRIAL REGISTRATION

German Clinical Trials Register (DRKS) DRKS00009753 and EudraCT database 2014-002918-23.

Plasma protein binding limits the blood brain barrier permeation of the pyrethroid insecticide, deltamethrin

Previous pharmacokinetic studies of deltamethrin (DLM) have revealed that brain levels of this highly lipophilic pyrethroid insecticide are only 15-20% of plasma levels. Experiments were performed to assess determinants limiting CNS access including plasma protein binding and the efflux transporter, P-gp. A human brain microvascular endothelial cell line, hCMEC/D3, was utilized as a model in vitro system to evaluate blood-brain barrier (BBB) permeation. Incubation of DLM with a series of human serum albumin (HSA) concentrations showed that unbound (fu) DLM ranged from 80% with 0.01% HSA to ∼20% at the physiologically-relevant 4% HSA. A positive correlation (R=0.987) was seen between fu and cellular uptake. Concentration-dependent uptake of DLM in 0.01% HSA was non-linear and was reduced at 4°C and by the P-gp inhibitor cyclosporine (CSA), indicative of a specific transport process. Cellular accumulation of [(3)H]-paclitaxel, a P-glycoprotein (P-gp) substrate, was increased by CSA but not by DLM, suggesting that DLM is neither a substrate nor an inhibitor of P-gp. The concentration-dependent uptake of DLM from 4% HSA was linear and not significantly impacted by temperature or CSA. In situ brain perfusion studies monitoring brain association of DLM at 0.01% and 4% HSA confirmed the aforementioned in vitro findings. This study demonstrates that brain uptake of DLM under normal physiological conditions appears to be a passive, non-saturable process, limited by the high protein binding of the pyrethroid.

Risk factors for human lice and bartonellosis among the homeless, San Francisco, California, USA

Results suggest that body lice disproportionately affect certain demographic groups and those who sleep outdoors.

Homeless persons in San Francisco, California, USA, have been shown to have head and body lice infestations and Bartonella quintana infections. We surveyed a self-selected population of homeless persons in San Francisco to assess infestations of head and body lice, risks of having body lice, and presence of B. quintana in lice. A total of 203 persons who reported itching were surveyed during 2008–2010 and 2012: 60 (30%) had body lice, 10 (4.9%) had head lice, and 6 (3.0%) had both. B. quintana was detected in 10 (15.9%) of 63 body lice pools and in 6 (37.5%) of 16 head lice pools. Variables significantly associated (p<0.05) with having body lice in this homeless population included male sex, African–American ethnicity, and sleeping outdoors. Our study findings suggest that specific segments of the homeless population would benefit from information on preventing body lice infestations and louseborne diseases.

Treatment of Pediculosis Capitis

An endeavour to delineate the salient details of the treatment of head lice infestation has been made in the present article. Treatment modalities including over the counter permethrin and pyrethrin, and prescription medicines, including malathion, lindane, benzyl alcohol, spinosad are discussed. Salient features of alternative medicine and physical treatment modalities are outlined. The problem of resistance to treatment has also been taken cognizance of.

Safety and efficacy of a 100% dimethicone pediculocide in school-age children

BACKGROUND

Head lice most commonly affect children, ages 3 to 11. Concerns exist about the safety and efficacy of pesticide-based treatments. Published studies suggest dimethicone is a potentially safe and effective non-toxic treatment, but have not evaluated 100% dimethicone in a pediatric population. The objectives were to evaluate the efficacy and safety of 100% dimethicone for the treatment of head lice in children, monitored by school nurses.

METHODS

This was a multi-site, open-label study of a 100% dimethicone gel for the treatment of head lice in a pediatric population. Children (ages 3-12) suspected of infestation with head lice were evaluated by school nurses at six schools and daycare programs in New York and New Jersey. Inclusion criteria were presence of at least three live lice, or one live louse and 10 viable eggs (eggs found within 1.27 cm of the scalp) and no use of any head lice treatment within four weeks of enrollment. Counts of live lice and viable eggs found in 58 subjects were tracked at baseline (Day 0) and on Day 1, Day 7, and Day 14 after treatment.

RESULTS

After 1 day of treatment with 100% dimethicone, 98.30% of subjects were free of live lice and 55.20% were free of viable eggs. On day 14, 96.50% were still free of live lice, and 80.70% were free of viable eggs. All subjects were monitored by the school nurse at baseline and throughout the study period for adverse effects, including scalp erythema, excoriation, flaking and edema. There was one adverse event of skin irritation lasting 10 min, and no serious adverse events reported. Overall, scalp conditions improved from the baseline: 10 subjects (17.5%) reported mild to moderate scalp erythema on day 1, compared with only one subject (1.7%) on day 14; 8 subjects (14.3%) reported mild scalp excoriation on day 1, with none reporting on day 14.

CONCLUSIONS

100% dimethicone was found to be a safe and highly effective treatment for pediatric head lice. Because dimethicone avoids pesticide exposure and resistance issues, dimethicone should be considered as a first-line treatment for head lice.

TRIAL REGISTRATION

NCT02213055 Date of registration: August 8, 2014. STANDARDS OF REPORTING: The CONSORT 2010 Checklist was consulted during the review of this manuscript. Please note that sections pertaining specifically to randomized controlled trials (RCT's) were not applicable.

Epidemiology of pediculosis capitis among schoolchildren in the eastern area of Bangkok, Thailand

OBJECTIVE

To determine the prevalence of infestation with head lice in primary schoolchildren in the eastern area of Bangkok, Thailand.

METHODS

The present study was to determine the head lice infestation (Pediculosis) levels in primary schoolchildren, during May, 2011 to July, 2011, A total of 3 747 schoolchildren aged 5-12 years old from 12 selected primary school of Ladkrabang district, the eastern area of Bangkok were examined for head lice. Pediculosis was defined as the presence of at least on living adult, nymph and viable egg.

RESULTS

The overall head lice infestation rate was 23.32% and infestation rate was higher in girls (47.12%) than in boys (0%). The infestation rate among schoolchildren varied from 12.62% to 29.76%. The infestation rate among girls varied from 26.07% (12 years old group) to 55.89% (8 years old group).

CONCLUSIONS

Pediculosis is a common public health problem affecting primary schoolchildren in eastern area of Bangkok and those levels are epidemic importance.

Infection Prevention and Control in Residential Facilities for Pediatric Patients and Their Families

The Society for Healthcare Epidemiology of America (SHEA) guideline “Infection Prevention and Control in Residential Facilities for Pediatric Patients and Their Families” is the first infection prevention and control (IPC) guideline to address preventing transmission of infectious agents in “home away from home” residential settings, of which the Ronald McDonald Houses (RMHs) serve as a prototype. These types of facilities provide support services, including overnight lodging, for ill and injured children and their families. Food preparation occurs in common areas, and cleaning of rooms or apartments is performed by the occupants during their stay and before departure. Pediatric patients are frequent guests of the family-centered facilities while receiving or recovering from specialized medical therapy. Examples of high-risk populations served in these facilities include families of patients with cancer, recipients of stem cell or solid organ transplants, surgical and/or very-low-birthweight infants who receive care in neonatal intensive care units (NICUs), those with cystic fibrosis, and women with high-risk pregnancies awaiting delivery in a nearby medical center. Such facilities are located worldwide and vary in their physical structure and the predominant population served.

Headlice eradication as everyday engagement with science: An analysis of online parenting discussions

This paper focuses on the way in which people deploy scientific knowledge alongside other resources in everyday interactions. In the UK headlice are common amongst schoolchildren, and treatment is viewed as a parental responsibility. Choice between treatment options lies with individual parents, with official guidance giving no clear steer. In the face of this combination of responsibility and uncertainty, users of an online parenting forum justify their actions using a variety of resources, including claims to scientific knowledge of both headlice and the action of various treatments, but also drawing on the authority of having direct experience, trust in brand-named products and generalised suspicion of "chemical" treatments. These discussions occasion expression of knowledge as part of portraying oneself as a responsible parent, and thus while they do not necessarily represent public knowledge about science more generally, they do offer a useful site to explore what people do with science.

Use of a poultry model to assess the transfer inhibition effect of head lice (Pediculus humanus capitis) products

Head lice (Pediculus humanus capitis) remain a nuisance, predominantly in school age children. Despite the availability of pediculicidal products, children, after treatment, easily become re-infested if the outbreak has not been controlled on a class or school level. Lice repellents and re-infestation deterrents have been developed to protect children post-treatment. In vitro assays, which are used to evaluate the performance of these products, have limited correlation to in vivo efficacy. In this study, a chicken model was developed as an alternative to in vitro models, more closely mimicking the in vivo situation of children at school. Chickens with natural infestations of Menopon spp. and Menacanthus spp. were divided into three groups and co-housed for 23 h: Group 1 was treated with a commercial product designed to kill lice and protect from re-infestation (Oystershell Laboratories); group 2 was used to assess lice re-population onto lice-free, untreated chickens; and group 3, the seeder group, consisted of lice-infested chickens. The chickens were examined for lice before and at regular intervals after treatment. The group 1 chickens had an average of 40 lice pre-treatment, 0 lice post-treatment and did not become re-infested during the 23-h period. Lice were slow to re-populate the group 2 chickens but were seen 3 h after co-housing with an average of 6 lice each at the end of the study. Group 3 chickens maintained their lice throughout the study (average of 32 at end of study). Based on this study, chickens can be used as a model to test the performance of lice repellents and re-infestation deterrents.

New drugs and devices from 2011 - 2012 that might change your practice

To be honest, I thought this would be a lost cause. Even after skipping a New Drugs and Devices essay in 2012, I figured that I would have to search long and hard to find 10 new things that emergency practitioners needed to know about. Although there were no true blockbuster medications for emergency physicians, I nonetheless found 10 medicines that we probably should know, along with a new device that may change the way we work up patients with palpitations, and a clever new delivery system for subcutaneous epinephrine.

Designing randomized-controlled trials to improve head-louse treatment: systematic review using a vignette-based method

Head-louse infestation remains a public health problem. Despite published randomized-controlled trials, no consensus-based clinical practice guidelines for its management emerged because of the heterogeneity of trial methodologies. Our study was undertaken to attempt to find an optimal trial framework: minimizing the risk of bias, while taking feasibility into account. To do so, we used the vignette-based method. A systematic review first identified trials on head-louse infestation; 49 were selected and their methodological constraints assessed. Methodological features were extracted and combined by arborescence to generate a broad spectrum of potential designs, called vignettes, yielding 357 vignettes. A panel of 48 experts then rated one-on-one comparisons of those vignettes to obtain a ranking of the designs. Methodological items retained for vignette generation were income level of the population, types of treatments compared, randomization unit, blinding, treatment-administration site, diagnosis method and criteria, and primary outcome measure. The expert panel selected vignettes with cluster randomization, centralized treatment administration, and blinding of the outcome assessor. The vignette method identified optimal designs to standardize future head-louse treatment trials, thereby obtaining valid conclusions and comparable data from future trials, and appears to be a reliable way to generate evidence-based guidelines.

Survey assessment on pediatricians' attitudes on head lice management

Background

Pediculosis capitis is a worldwide health problem. One of the most important factor in effective head lice eradication is to ensure that infestation is adequately recognized and treated. Our survey investigated the knowledge and practice among primary care Italian pediatricians regarding to the prevention and treatment of head lice.

Methods

The questionnaire was distributed to all the pediatricians registered at the Annual Congress of Practice in Pediatrics held in Florence, Italy, November 11–12, 2011. It includes 10 questions in a multiple choice format, and one answer for each question was provided. The questionnaire was conceived by pediatricians at the Infectious Disease Unit of the Department of Science for the Health of Woman and Child, University of Florence. Questions were designed according to the guidelines by the Italian Pediatric Society (SIP), and international guidelines, such as the Centers for Disease Control and Prevention (CDC), and the American Academy of Pediatrics (AAP).

Results

Overall, 364/600 pediatricians (60.7% of physicians registered to the Congress) returned the questionnaire. The majority of them (232/364; 63,7%) believe that parents consult their primary care pediatrician only after the failure of other “remedies”. Mostly, they prescribe Malathion (116/364, 31,8%) as first line treatment. Two-hundred-fourty-three (66.7%) of participants consider creams, foams and gels the most effective formulations. Two-hundred-sixty-two of pediatricians interviewed (72.0%) suggest to repeat the treatment after one week, 37/364 (10.2%) after two weeks. The majority of the pediatricians interviewed reported that recurrences occur in less than 30% of cases (279/364; 76,6%). In their own opinion, most of recurrences are the consequence of a reinfestation in the community (259/264; 77%). Three-hundred-thirty-four (91.7%) of them have never prescribed oral therapy for the treatment of head lice. Finally, 289/364 (79.4%) pediatricians believe that no product is effective for prevention.

Conclusions

This is the first study that investigates the clinical practice of family pediatricians about the management and treatment of head lice globally, the Italian pediatricians surveyed proved to be quite informed on the head lice management. However, even in a country where pediatric assistance is free for everybody, a considerable proportion of parents do not seek advice to their own family pediatrician. Therefore, educations of parents, other than continuous updating of pediatricians, may contribute to a better management of head lice in the community.

Topical Ivermectin 0.5% Lotion for Treatment of Head Lice

Objective: To investigate the pharmacology, pharmacokinetics, efficacy, adverse effects, and place in therapy of a single application of topical ivermectin 0.5% lotion for head lice treatment. Data Sources: Literature was obtained by searching MEDLINE, PubMed, CINAHL, and Scopus (January 1980 to January 2013). Abstracts were searched for the terms ivermectin AND (head lice or pediculus or pediculosis), topical ivermectin, ivermectin lotion, ivermectin AND (pharmacology OR pharmacokinetics). The New Drug Application filed with the Food and Drug Administration and the product data sheets for ivermectin were obtained. Study Selection and Data Extraction: All English-language articles retrieved from the search were evaluated for relevance to the objective. Data Synthesis: The recommended first-line head lice treatments in the United States are permethrin 1% or pyrethrins, with malathion 0.5% lotion used as a second-line treatment. Significantly more of the 289 head lice–infested participants using topical ivermectin 0.5% lotion were lice-free at day 15 when compared with vehicle control (73.8% vs 17.6%; P < .001) in 2 studies. Although this rate is lower than other third-line treatments (eg, spinosad 0.9% or benzyl alcohol 5%), topical ivermectin 0.5% lotion is well tolerated (pruritus, the most common adverse event, 0.9%) and requires only a single application. Conclusions: Topical ivermectin 0.5% lotion kills head lice by increasing chloride in muscle cells, causing hyperpolarization and paralysis. Only 1 application is required; when the treated eggs hatch, the lice are not viable because they cannot feed as a result of pharyngeal muscle paralysis. Minimal systemic absorption occurs following topical application. Studies have demonstrated that topical ivermectin 0.5% is a safe and efficacious treatment for head lice. Although it has no documented resistance, there is limited clinical experience, it requires a prescription, and it is expensive. Therefore it should be reserved as a third-line treatment for head lice in the United States.

Assessment of the safety and efficacy of three concentrations of topical ivermectin lotion as a treatment for head lice infestation

BACKGROUND

Ivermectin is a broad-spectrum parasiticide in widespread systemic use, including as an off-label treatment for head lice infestation. The potential of the topical use of ivermectin as a treatment for head lice infestation was suggested by an in vitro report of a novel lotion formulation.

OBJECTIVES

This study investigated the relative effectiveness of three ivermectin lotion concentrations (0.15, 0.25, and 0.5%) compared with vehicle placebo in eliminating head lice infestation.

METHODS

In this randomized, blinded study, 78 head lice-infested subjects, aged 2-62 years, received a single, 10-minute application of product on day 1. Evaluations were completed at two and six hours post-application, and on days 2, 8 (±1), and 15 (+2). Safety was assessed according to the evaluations of trained observers and adverse event (AE) reports. Efficacy was assessed according to scalp and hair examinations.

RESULTS

Compared with placebo, all ivermectin concentrations resulted in the statistically significant (P ≤ 0.003) eradication of head lice through to day 15, with the highest level of eradication (73.7%) in subjects who received the 0.5% concentration. The severity of pruritus decreased from baseline in all treatment groups, including the placebo group, from six hours post-treatment to day 15, with the greatest reduction in the 0.5% concentration group. No ocular irritation was observed. All three ivermectin treatment strengths and vehicle were well tolerated.

CONCLUSIONS

A single application of a 0.5% concentration of this ivermectin lotion formulation shows promise as a safe and effective treatment for head lice infestation and the associated signs of pruritus.

Pharmacokinetics and safety of 0.5% ivermectin lotion for head louse infestations

The safety of a novel 0.5% ivermectin lotion (IVL) and potential for ivermectin absorption after application was investigated in an open-label study in young children, and a human repeat insult patch test (HRIPT) and cumulative irritation test (CIT) assessed any potential for cumulative dermal irritation and contact sensitization. In the pharmacokinetic and safety study, 30 head louse-infested children ages 6 months to 3 years received a 10-minute application of IVL on day 1. Blood was collected before application; 0.5, 1, and 6 hours after rinsing; and on days 2 and 8. Samples from 20 subjects were assayed for ivermectin (test sensitivity 0.05 ng/mL). Liver panel and complete blood counts were completed for all subjects. For the HRIPT/CIT, occlusive patches containing IVL or vehicle control lotion (CL) were repeatedly applied to 220 healthy adult subjects to assess contact sensitization; for cumulative dermal irritation testing, additional patches with normal saline and sodium dodecyl sulfate (SDS) were applied to 36 subjects. In the open-label study, all detected ivermectin plasma concentrations were <1 ng/mL. No safety signals emerged, and treatment was well tolerated. In the HRIPT/CIT, IVL was significantly less irritating than normal saline and SDS, with no evidence of dermal irritation or sensitization in human skin. IVL was safe when applied topically, absorption was de minimus, there was no evidence of irritation or sensitization from repeated exposures, and results support the safety of topical IVL use in children as young as 6 months.

Recent new drug approvals. Part 1: drugs with pediatric indications

This two-part review provides information about drugs that have been recently approved by the Food and Drug Administration and focuses on drugs approved with pediatric indications or approved in adults with active pediatric studies. Information was obtained from the product labeling and selected published studies. Part 1 reviews recently approved drugs with labeled pediatric indications, and Part 2 will review recent drug approvals in adults that have potential use in pediatrics and have active studies.

Spinosad: An effective and safe pediculicide

Although head lice are not a major health hazard, they have been a source of irritation and disgust for thousands of years. Despite the use of over-the-counter (OTC) treatments, it has high prevalence, and epidemics occur regularly. Permethrin 1% is currently recommended as a drug of choice, but many areas have shown resistance to this insecticide. A 0.9% suspension of spinosad, a naturally occurring pest control product, has recently been approved by the USFDA for treatment of pediculosis capitis. It acts by enhancing the action of nicotinic acetylcholine, resulting in paralysis of the parasite. Clinical trials show that spinosad is more effective and safe than current drugs of treatment. Additionally, it does not require nit combing. Spinosad appears as a powerful recruit in the battle against head lice.

Advancements in the treatment of head lice in pediatrics

Head lice infestations occur commonly each year in children of all socioeconomic statuses. However, head lice have become more of a nuisance as resistance to first-line agents, such as permethrin 1% and pyrethrins, has increased. Newer topical products provide unique mechanisms of action without current signs of resistance. As with older agents, proper application of products must be emphasized to ensure that treatment is effective. In addition, nonpharmacologic measures should be taken to avoid reinfestation in the patient and to prevent the spread of lice to close personal contacts.