Head lice in schoolchildren

HEAD LOUSE PALEOEPIDEMIOLOGY IN THE OSMORE RIVER VALLEY, SOUTHERN PERU

Recent studies of louse ectoparasites from mummies have developed robust data sets that allow a true epidemiological approach to the prehistory of louse parasitism. One epidemiological principle is that the binomial of overdispersion is normally negative, meaning that in a host population, parasites are aggregated in a few individuals. We demonstrate the overdispersion of lice in 3 different prehistoric communities that differ along 3 axes or variables: environmental setting, socioeconomic status, and cultural affiliation. Distinct cultural practices could have been involved in different patterns of louse infestation. Prevalence, intensity, and abundance of infestations exhibit statistically significant differences between the communities. We also find differences in prevalence between subadults and adults that contrasted by cultural affiliation and suggest conditions different from those seen today. We show that overall prevalence was affected primarily by ecological setting, not socioeconomic status nor cultural affiliation. These findings demonstrate that statistical analysis of archaeological data can reveal the states of infestation in past populations with lifestyles not seen in modern people. Our approach paves the way for future comparisons of subpopulations within archaeological communities.

Explaining the Determinants of Pediculosis Control and Prevention: A Qualitative Study in Southern Iran

In many regions of the world, human head lice infestations caused by Pediculus capitis are a major health concern among school-aged children. This study was carried out to explain variables influencing pediculosis prevention and control from the perspective of parents and teachers of female elementary school pupils, as well as healthcare practitioners in Bandar Abbas, Iran. Participants in this qualitative study included 23 participants, including parents and teachers of primary school girls, as well as healthcare practitioners. Purposive sampling was employed and sustained until data saturation was reached. Data was acquired through in-depth interviews and evaluated using content analysis in the form of constant comparison. To assess the quality of the outcomes, Lincoln and Guba’s criteria were used. The data were extracted into 2 primary categories, including challenges and facilitators to controlling pediculosis, each with several subcategories as follows: 1) economic-political aspects; 2) family factors; 3) social-cultural elements; 4) personal and mental issues; 5) geographical position of the investigated region; 6) school and education factors; and 7) factors related to medications and therapy. There were 2 types of facilitators: 1) informative factors and 2) social-cultural variables. According to the findings, pediculosis prevention, control, and treatment necessitate multifaceted and multi-level intervention. Some solutions must be addressed at the personal-psychological, familial, political-economic, geographical, and informational levels, as well as school-related concerns, social stigma elimination, and evaluation of cultural components of the issue at the social level.

Efficacy of Peer Education for Adopting Preventive Behaviors against Head Lice Infestation in Female Elementary School Students: A Randomised Controlled Trial

BACKGROUND

Pediculosis is a common parasitic infestation in students worldwide, including Iran. This condition is more prevalent in populous and deprived communities with poor personal hygiene. This study sought to assess the efficacy of peer education for adopting preventive behaviors against pediculosis in female elementary school students based on the Health Belief Model (HBM).

METHODS

A total of 179 female fifth grade students were selected using multistage random sampling and were randomly allocated to control and intervention groups. A standard questionnaire was designed and administered to collect baseline information. An educational intervention was then designed based on the conducted needs assessment. The educational program consisted of three sessions, held by peers for the intervention group. The questionnaire was re-administered one month after the intervention. Independent and paired t-test, Pearson's correlation coefficient, and regression analysis were applied as appropriate.

RESULTS

The two groups had no significant differences in the scores of knowledge, HBM constructs, or behavior before the intervention. After the intervention, however, the mean scores of all parameters significantly improved in the intervention group.

CONCLUSION

Peer education based on HBM is an effective strategy to promote preventive behaviors against pediculosis in among fifth grade female elementary school students in Iran.

Management and Treatment of Human Lice

Of the three lice (head, body, and pubic louse) that infest humans, the body louse is the species involved in epidemics of louse-borne typhus, trench fever, and relapsing fever, but all the three cause pediculosis. Their infestations occur today in many countries despite great efforts to maintain high standards of public health. In this review, literature searches were performed through PubMed, Medline, Google Scholar, and EBSCOhost, with key search words of "Pediculus humanus", "lice infestation", "pediculosis", and "treatment"; and controlled clinical trials were viewed with great interest. Removing lice by hand or with a lice comb, heating infested clothing, and shaving the scalp were some of the oldest methods of controlling human lice. Despite the introduction of other resources including cresol, naphthalene, sulfur, mercury, vinegar, petroleum, and insecticides, the numbers of lice infestation cases and resistance have increased. To date, viable alternative treatments to replace insecticides have been developed experimentally in vitro. Today, the development of new treatment strategies such as symbiotic treatment and synergistic treatment (antibiotics + ivermectin) in vitro has proved effective and is promising. Here, we present an overview on managing and treating human lice and highlight new strategies to more effectively fight pediculosis and prevent resistance.

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.

Head lice

Head lice infestation is associated with limited morbidity but causes a high level of anxiety among parents of school-aged children. Since the 2010 clinical report on head lice was published by the American Academy of Pediatrics, newer medications have been approved for the treatment of head lice. This revised clinical report clarifies current diagnosis and treatment protocols and provides guidance for the management of children with head lice in the school setting.

Prevalence of head lice and hygiene practices among women over twelve years of age in Sindh, Balochistan, and North West Frontier Province: National Health Survey of Pakistan, 1990-1994

BACKGROUND

Head lice infestation is an infection of the scalp and skin which causes blood loss, discomfort, and social and psychological distress with the possibility of secondary bacterial infections occurring at scratch sites. In Pakistan, although some small scale studies have been conducted to investigate prevalence of head lice in school children and the general population, no population based estimates have been reported. The National Health Survey of Pakistan (NHSP 1990 - 94) was a nationally representative health examination survey of the Pakistani population. The NHSP is the first population based household survey to collect data on the prevalence of head lice in adult women in Pakistan. In this paper we use data from the NHSP to present an epidemiological profile of personal hygiene practices and head lice infestation among women aged 12 years or older in three provinces of Pakistan; Balochistan, Sindh and North West Frontier Province (NWFP).

RESULTS

Overall about 7% women aged 12 years and older suffered from head lice infestation. Multivariable logistic regression analysis identified factors independently associated with presence of head lice. Age less than 16 years and crowding at home were associated with higher infestation-rates. The impact of household socio-economic status on infestation rates among women was different in urban and rural settings; urban women with low socio-economic status were more vulnerable than similar women in rural settings. Bathing infrequently in summer was associated with higher prevalence rates only in Sindh, possibly due to the fact that among the three provinces Sindh has a hotter and more humid summer.

CONCLUSIONS

The results of our analysis of NHSP indicate high levels of head lice infestation among girls and women in the three Provinces. The epidemiological profile of hygienic practices of women indicated that NWFP and Balochistan as compared to Sindh, and rural as compared to urban areas were less developed with respect to access to water supply and soap for maintaining personal hygiene. Simple and cost-effective measures such as provision of water and soap, and improving awareness regarding maintaining personal hygiene can contribute significantly towards improving public health status of the women in Pakistan.

Oral ivermectin for head lice: a comparison with 0.5 % topical malathion lotion

BACKGROUND

Reports of treatment failure of head lice have become increasingly common. Oral ivermectin has been proposed as a potential alternative for the treatment of head lice infestation. The aim of this study was to compare the efficacy of oral ivermectin with topical malathion lotion in the treatment of head lice.

PATIENTS AND METHODS

Eighty apparently healthy children with head lice infestation were randomly assigned to 2 groups, with 40 patients in each. The first group received oral ivermectin as a single dose of 200 μg/kg and the second group received single topical application of malathion lotion 0.5%. Follow up visits were done at days 8, 15 and 29. A second dose of either drug was given at day 8 in case of treatment failure.

RESULTS

After a single dose, complete cure was achieved in 77.5% and 87.5% of ivermectin and malathion groups respectively. After the second dose for nonresponders, the cure rate increased to 92.5% in the ivermectin group and 95% in the malathion group. No major adverse effects were observed in either group.

CONCLUSIONS

Oral ivermectin is a promising effective approach for the treatment of head lice and could be an ideal substitute for conventional pediculicides.

Head lice

Head lice infestation is associated with limited morbidity but causes a high level of anxiety among parents of school-aged children. Since the 2002 clinical report on head lice was published by the American Academy of Pediatrics, patterns of resistance to products available over-the-counter and by prescription have changed, and additional mechanical means of removing head lice have been explored. This revised clinical report clarifies current diagnosis and treatment protocols and provides guidance for the management of children with head lice in the school setting.

The impact of well-developed preventative strategies on the eradication of head lice

In the 1970s Donaldson applied the principles of infectious disease surveillance to pediculosis capitis infestation with head lice. This provided a lasting insight into an effective strategy for prevention. Research in Teesside, UK, proved that the first step in breaking the chain of transmission is the engagement of parents in an intensive detection/treatment campaign. United action halved the infestation rate, even though failing lindane treatments were in use. Subsequently although effective malathion treatment was introduced, it became clear that the late detection of light cases of head lice still undermines eradication. This paper analyzes the development by the health charity, Community Hygiene Concern, of the Bug Busting programme based on this solid evidence. In the 1990s the charity solved the problem of detecting asymptomatic lice using a specially designed Bug Buster louse comb in wet, conditioned hair. It undertook the popularization of this method and the co-ordination of national detection days (Bug Busting Days) through primary schools. In 2004 this structured approach to prevention was adopted in Chester. It produced a 24% reduction in health authority spending on treatment products in the first year and appreciable savings in professional time. It is concluded that participation in the Bug Busting programme benefits community health providers and schools. Provision of dependable detection combs with the correct instructions to families at risk, empowers them to gain sustainable, cost-effective control of head lice.

Fomite transmission in head lice

Control of various infestations requires an accurate understanding of transmission. After thousands of years of lice infestation, scientific documentation of indirect contact transmission has been substantiated. Lice can be transferred in the egg, instar, and adult stages. Lice have now been shown in the laboratory to be readily dislodged by air movements such as blow-drying one's hair, combing, and toweling. Moreover, passive transfer to adjoining fabric is also frequently observed. Louse transmission by fomites occurs more frequently than has been commonly believed. Close proximity suffices to increase the likeliness of a new infestation. Thus louse control measures should take account of fomite transmission and include screening of all individuals within an infested person's immediate circle of contact, laundering of everything within the infested individuals' bed or quarantining of such material for 10 days, thorough vacuuming of floors, carpets, upholstery, with a standard vacuum cleaner.

Pediculosis capitis

Pediculosis capitis is a worldwide public health concern. Infestation occurs most commonly in children, with a peak incidence between 5 to 11 years of age. The condition is more common in girls and less common in Black children. Direct head-to-head contact is the most common mode of transmission. Pruritus is the most common symptom of infestation. The gold standard for diagnosing pediculosis capitis is finding a live louse or nymph in the scalp or viable egg in the scalp hair. Pediculicides are the most effective treatment. All household members and close contacts should be examined and treated concurrently if infested. The child should be allowed to return to school or to a child care facility after proper treatment. The child should be discouraged from close, direct head contact with others or from sharing items that have come in contact with the hair.

A simple treatment for head lice: dry-on, suffocation-based pediculicide

OBJECTIVES

The emergence of drug-resistant lice has created the need for new therapies. This study assesses a new method without neurotoxins, extensive household cleaning, or nit removal.

METHODS

One hundred thirty-three subjects participated in 2 open clinical trials. In the first trial, 93 subjects completed treatment using a nontoxic, dry-on, suffocation-based, pediculicide lotion, minimal household cleaning measures, and physical removal of the nits. In the second trial, 40 subjects completed treatment using an identical protocol except that the nits were not removed. Head lice infestation was defined as a wet combing test showing lice. Cure was defined as a wet combing test showing no lice, with an absence of symptoms. Subjects were contacted 6 months later, for assessment of their disease status.

RESULTS

Cure was achieved for 97% of the patients in the first trial and 95% in the second trial. Remission at the follow-up assessment was reported for 77 of 82 subjects (94%) in the first trial and 36 of 38 subjects (95%) in the second trial. There was no statistical difference in cure rates or remission rates between the protocols with and without nit removal. The overall cure rate was 96%, with a remission rate of 94%. There were no adverse effects.

CONCLUSIONS

Dry-on, suffocation-based, pediculicide lotion effectively treats head lice without neurotoxins, nit removal, or extensive house cleaning. These results are comparable or superior to the results previously reported for treatments with permethrin, pyrethrin, and malathion.

Louse infestation of the Chiribaya culture, southern Peru: variation in prevalence by age and sex

In order to improve the interpretive potential of archaeoparasitology, it is important to demonstrate that the epidemiology of ancient parasites is comparable to that of modern parasites. Once this is demonstrated, then we can be secure that the evidence of ancient parasitism truly reflects the pathoecology of parasitic disease. Presented here is an analysis of the paleoepidemiology of Pediculus humanus infestation from 146 mummies from the Chiribaya culture 1000-1250 AD of Southern Peru. The study demonstrates the modern parasitological axiom that 10% of the population harbors 70% of the parasites holds true for ancient louse infestation. This is the first demonstration of the paleoepidemiology of prehistoric lice infestation.

Wet combing for head lice: feasibility in mass screening, treatment preference and outcome

There is no scientific consensus on the best way to control head louse infestation in schoolchildren. A study was conducted to test the feasibility and acceptability of a screening campaign by wet combing and a community approach to head-louse control with home visits, and to explore parents' treatment preferences and treatment outcomes. A non-controlled intervention (advice on treatment options offered to all positive children) was nested within an epidemiological prevalence study. All children in three primary schools in Ghent, Belgium, were invited to take part in screening by wet combing (n=677, 3-11 years). Positive children were offered structural treatment advice, a home visit on day 7, and a check by wet combing on day 14. 83% of the children were screened. The prevalence of active infestation (living moving lice) was 13.0% in school 1 and 19.5% in school 3. In school 2, prevalence of signs of active and past infestation was 40.7%. A home visit was made to 58% of the positive children. 85% of the positive children were screened again on day 14. Wet combing was the most widely used treatment, followed by chemical treatment and a combination of the two. In school 1 and 3 51% were cured, and in school 2 24% became nit-free. A wet combing screening campaign and a community-oriented approach to head-louse control is feasible though resource-intensive. The prevalence of head lice was high and the cure rate was low, with either topical treatments or wet combing.

Wet Combing for Head Lice: Feasibility in Mass Screening, Treatment Preference and Outcome

There is no scientific consensus on the best way to control head louse infestation in schoolchildren. A study was conducted to test the feasibility and acceptability of a screening campaign by wet combing and a community approach to head-louse control with home visits, and to explore parents’ treatment preferences and treatment outcomes. A non-controlled intervention (advice on treatment options offered to all positive children) was nested within an epidemiological prevalence study. All children in three primary schools in Ghent, Belgium, were invited to take part in screening by wet combing (n=677, 3–11 years). Positive children were offered structural treatment advice, a home visit on day 7, and a check by wet combing on day 14.

83% of the children were screened. The prevalence of active infestation (living moving lice) was 13.0% in school 1 and 19.5% in school 3. In school 2, prevalence of signs of active and past infestation was 40.7%. A home visit was made to 58% of the positive children. 85% of the positive children were screened again on day 14. Wet combing was the most widely used treatment, followed by chemical treatment and a combination of the two. In school 1 and 3 51% were cured, and in school 2 24% became nit-free. A wet combing screening campaign and a community-oriented approach to head-louse control is feasible though resource-intensive. The prevalence of head lice was high and the cure rate was low, with either topical treatments or wet combing.

Towards the eradication of head lice: literature review and research agenda

Head lice infestation is a public health issue. In the effort to compile an evidence-base about the physiology, detection, treatment, effects and management strategies of head lice infestations we reviewed current literature. This literature signalled significant evidence gaps and these gaps provide incentives for further research. Our conclusions from the literature are that parents of children are responsible for head lice detection and treatment but have varying access to advice about how best to treat this condition. Concern is exacerbated by misconceptions surrounding the circumstances of infestation. Head lice are a low priority for health professionals in Australia, whereas parents and teachers believe the problem necessitates greater attention. It is important to provide a unified evidence-based approach to good information. It is timely for health care professionals to re-examine and prioritize this public health issue. They should research and work collaboratively towards the eradication of head lice.

Head lice resistance: itching that just won't stop

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.

Scanning electron microscopy of adult head lice (Pediculus humanus capitis) with focus on clinical implications

BACKGROUND

The incidence of head lice infestations in North America is escalating with an estimated 12 million cases of head lice per year despite the existence of insecticidal therapies.

OBJECTIVE

To evaluate certain characteristics of the human head louse, including their chitinous structure, nymphal developmental stages, legs with claw adaptations, antennae with sensory perceptions, and spiracles by which oxygen exchange occurs, for assessment of possible means to control the spread and growth of this insect.

METHODS

Scanning electron-microscopic examination of head lice was performed.

RESULTS

Newer treatments of head lice must acknowledge defense mechanisms that are based on anatomic structure and physiologic characteristics, details of louse transmission, and the insects' ability to 'resurrect' after sham death.

CONCLUSIONS

An understanding of lice entomology is essential in the pursuit of novel means to control the lice epidemic.

Comparison of wet combing with malathion for treatment of head lice in the UK: a pragmatic randomised controlled trial

BACKGROUND

Concern about the effectiveness and toxicity of insecticide lotions has led to promotion of mechanical methods to remove head lice. We compared the effectiveness of "bug-busting" (wet combing with a fine-toothed comb) and malathion lotion.

METHODS

We screened 4037 schoolchildren in two counties in Wales, UK (intermediate resistance to malathion). Of 167 found to have head lice, 81 (aged 3-14 years) were eligible to participate in a randomised controlled trial that compared mechanical removal of lice by a commercial kit every 3-4 days for 2 weeks with two applications of 0.5% malathion lotion 7 days apart; parents carried out both treatments. The outcome measure was the presence of live lice 7 days after the end of treatment. Analyses were by intention to treat.

FINDINGS

74 children completed the study and 72 were included in the analysis. The cure rate was 38% (12 of 32) for bug-busting and 78% (31 of 40) for malathion. Children assigned bug-busting were 2.8 (95% CI 1.5-5.2) times more likely than those assigned malathion to have lice at the end of treatment (p=0.0006).

INTERPRETATION

Malathion lotion was twice as effective as bug-busting, even in an area with intermediate resistance. Policies advocating bug-busting as first-line treatment for head lice in the general population are inappropriate. Assessment of the outcome of treatment 1-2 weeks after completion is essential for successful management. Only about 50% of participants complied fully with treatment, so future trials should be pragmatic in design, avoid false incentives, and study representative samples of children.

Head lice: is there a solution?

Head lice is an old problem that won't go away. Infestation with the head louse Pediculus capitis is still common in school-aged children. The majority of information about this condition is based on anecdotal evidence. There is a definite need for the standardization of detection methods for diagnosis and epidemiological purposes, and for properly designed trials to ascertain the effectiveness of the different treatment methods available.

Prevention and treatment of head lice in children

Head louse infestations (pediculosis) are prevalent worldwide. In developed countries, the infestation rate of 4- to 13-year-old children remains high despite preventive efforts. This is due to the existence of numerous ineffective pediculicides, the incorrect use of the effective agents, toxicological concerns and the development of louse strains resistant to insecticides. One of the most effective tools for the prevention and control of lice is the louse comb, which should be used regularly for the detection of living lice at an early stage of infestation, and as an accessory to any treatment method to remove living and dead lice. The louse comb can also be used systematically for the treatment of infestations, for confirmation that treatment with pediculicides has been successful, and for the removal of nits (dead eggs or egg shells). Most pediculicides are only partially ovicidal. Therefore, 10 days after beginning treatment with any antilouse product, the scalp of the child should be examined. If no living lice are found, the treatment should be discontinued. If living lice are still present, treatment should be continued with a product containing a different active ingredient. Suffocating agents such as olive, soya, sunflower and corn oils, hair gels and mayonnaise are able to kill a significant number of lice only if they are applied in liberal quantities for more than 12 hours. However, they lubricate the hair and therefore may facilitate combing and removing lice and eggs from the scalp. Nits may remain glued on the hair for at least 6 months, even after a successful treatment, and lead to a false positive diagnosis of louse infestation. If nits are seen on the hair, the child should be examined, but treatment should be initiated only if living lice are found. Formulations containing 5% acetic acid or 8% formic acid, as well as acid shampoos (pH 4.5 to 5.5) and conditioners, in combination with a louse comb, can be helpful for removing nits. There is no conclusive evidence that using essential oils to repel lice is effective. Regular examination of the child's head using a louse comb is the best measure to detect re-infestation at an early stage. Educating caregivers, nurses and teachers about louse biology, epidemiology, prevention and control is of paramount importance. The psychological effect of an infestation with lice is significant and often associated with anxiety and fear. The child should not be made to feel responsible for having lice, or be punished or reprimanded.

An assessment of topical and oral prescription and over-the-counter treatments for head lice

A plethora of head lice cases that require optimal therapeutic assessments are developing in elementary schools. Over-the-counter therapies continue to be the mainstream solution for most cases of pediculosis capitis, but the onset of resistant cases dictates a review of available treatment modalities. The increased efficacy of prescription drugs, namely topical 5% permethrin and oral ivermectin, underline the expanding role that physicians will serve in the eradication of head lice in our communities.