Global output of research on epidermal parasitic skin diseases from 1967 to 2017.

BACKGROUND: Epidermal parasitic skin diseases (EPSD) occur in most countries and cause a considerable health and economic burden, particularly in the tropics and subtropics. The aim of this study was to assess and analyse peer-reviewed literature on EPSD in humans. The results of this study serve as an indicator of the extent the scientific community, health authorities, and international health agencies interact with EPSD as a health problem that is commonly associated with poverty and poor hygiene. METHODS: A bibliometric analysis methodology was used. The Scopus database was used to retrieve documents about EPSD for the study period (1967-2017). The study focused on scabies, tungiasis, pediculosis, hookworm-related cutaneous larva migrans (HrCLM), myiasis, and cutaneous strongyloidiasis. Documents that specifically and explicitly discuss EPSD in animals, aquatic organisms, and birds were excluded. RESULTS: In total, 4186 documents were retrieved. A fluctuated growth of publications on EPSD in the past five decades was found. The retrieved documents received 43 301 citations, an average of 10.3 citations per article and an h-index of 74. The keywords "scabies" and was the most commonly encountered keyword followed by the keywords "head lice" and "pediculosis". The most active journal involved in publishing articles on EPSD was the International Journal of Dermatology (164; 3.9%). Researchers from 93 different countries published the retrieved articles. The USA led with 735 (17.6%) documents, followed by the UK (274; 6.5%), and Germany (259; 6.2%). In terms of institutions, the Charité - Universitätsmedizin Berlin in Germany was the most active in this field with 78 (1.9%) publications, followed by the Universidade Federal do Ceará in Brazil with 52 (1.2%) publications. CONCLUSIONS: Research on scabies and pediculosis dominated the field of EPSD research to the expense of tungiasis, HrCLM, myiasis, and cutaneous strongyloidiasis. There was an underrepresentation of literature from the tropics and subtropics despite EPSD being common in these areas. This could possibly be explained by the presence of limited number of non-English journals in the Scopus database. International research collaborations and research networking should be strengthened to help advance and prioritize research on EPSD.

Impact of family ownerships, individual hygiene, and residential environments on the prevalence of pediculosis capitis among schoolchildren in urban and rural areas of northwest of Iran.

In the appraisal of head lice outbreak, in addition to socioeconomic factors and availability of health care services, environmental conditions of the households must be taken into account. However, interviewing with children or mailing questionnaires to families may not reflect the actualities. Therefore, in this study, all the inclusive factors which may be associated with head lice outbreak were thoroughly and closely investigated. The data were collected by examining students at schools and surveying patients' households. A questionnaire concerning children's personal hygienic practices, family features, and environmental conditions of the households was filled out during the close assessment of the residential area. The overall prevalence of head lice was obtained as 5.9%, and the difference was not significant within the urban (5.1%) and rural (6.1%) communities. Overall, the number of infested students was more frequent in girls (6.6%) than boys (2.8%), but the difference was not significant. The highest infestation rate was obtained in the examined students whose fathers were unemployed, farmer, and herdsman. Family income showed greater correlation with the prevalence of pediculosis capitis. A high frequency of pediculosis capitis was identified among the students who were sharing individual items with siblings. Assessment of households showed that room flooring material and keeping animals at home were highly correlated with head lice prevalence. Households should be informed that infestations happen, irrespective of socioeconomic status. However, the physical and environmental conditions of living areas and households play an important role in head lice prevention.

Prevalence of head lice in two socio-economically different schools in the center of Izmir City, Turkey.

OBJECTIVE: The well-known and common infestation caused by Pediculus humanus capitis is an important public health and a social issue in many communities in the world. The aim of this study was to compare the head louse infestation rate in two schools having pupils from different socio-economic levels in the city center of Izmir. METHODS: The pupils aged between 6 and 11 years, were screened for the presence of eggs and nymph/adult lice using a fine-tooth head louse comb. RESULTS: A total of 88 and 126 pupils from the schools with low and medium socio-economic level were screened and 24 (27.2%) and 5 (3.96%) of them were found to be positive for head lice, respectively. Overall, the infestation rate among girls was 3.14 times higher than in boys. CONCLUSION: Head louse infestation is a significant public health problem among primary schools. Increasing the knowledge about pediculosis and self-hygiene would be helpful in successfully reducing head louse infestation in the school setting. School authorities must encourage the parents to look for head lice routinely and a "school nurse" system is needed for effective head louse control in the schools.

Guidelines for treatment of lice in sheep with long wool based on a model of the development of wool damage.

OBJECTIVE: This study used a model of the development of wool damage caused by lice in long wool to examine the conditions under which treatment of the sheep is advisable on an economic basis. METHODS: The model uses the proportion of a flock showing visible signs of rubbing and the number of days until the next shearing to compare the cost of treatment (product plus labour) with production losses because of the reduction in wool value caused by lice. From the model output, guidelines are provided to inform producers of the most cost-effective option for lice control. RESULTS: Under normal conditions, if there are any signs of rubbing ≥140 days before shearing, then treatment was the best option. If signs of wool damage are not observed until there are ≤70 days before shearing, then the most cost-effective option is to not treat at all. Between these two periods, the time period in which not treating is the most cost-effective option decreases as the number of sheep visibly affected by lice increases. At higher wool values (A$70/head vs A$35), the option to treat is brought forward approximately 25 days, whereas at a low wool value (A$17.50/head) the period in which no treatment is the most cost-effective is extended by approximately 25 days. Treating only the visibly affected sheep is the best option only for a very short time for all wool values and treatment costs. CONCLUSION: The model provides guidelines for control of lice in long wool to minimise the net cost of infestation and limit unnecessary pesticide use.

Head lice surveillance on a deregulated OTC-sales market: a study using web query data.

The head louse, Pediculus humanus capitis, is an obligate ectoparasite that causes infestations of humans. Studies have demonstrated a correlation between sales figures for over-the-counter (OTC) treatment products and the number of humans with head lice. The deregulation of the Swedish pharmacy market on July 1, 2009, decreased the possibility to obtain complete sale figures and thereby the possibility to obtain yearly trends of head lice infestations. In the presented study we wanted to investigate whether web queries on head lice can be used as substitute for OTC sales figures. Via Google Insights for Search and Vårdguiden medical web site, the number of queries on "huvudlöss" (head lice) and "hårlöss" (lice in hair) were obtained. The analysis showed that both the Vårdguiden series and the Google series were statistically significant (p<0.001) when added separately, but if the Google series were already included in the model, the Vårdguiden series were not statistically significant (p = 0.5689). In conclusion, web queries can detect if there is an increase or decrease of head lice infested humans in Sweden over a period of years, and be as reliable a proxy as the OTC-sales figures.

Head lice in Norwegian households: actions taken, costs and knowledge.

INTRODUCTION: Head lice infestations cause distress in many families. A well-founded strategy to reduce head lice prevalence must shorten the infectious period of individual hosts. To develop such a strategy, information about the actions taken (inspection, treatment and informing others about own infestations), level of knowledge and costs is needed. The present study is the first to consider all these elements combined. MATERIALS AND METHODS: A questionnaire was answered by 6203 households from five geographically separated municipalities in Norway. RESULTS: 94% of the households treated members with pediculicides when head lice were discovered. Nearly half of the households checked biannually or not at all. Previous occurrence of head lice and multiple children in a household improved both checking frequency and method. More than 90% of the households informed close contacts about their own pediculosis. Direct costs of pediculosis were low (less than €6.25 yearly) for 70% of the households, but the ability to pay for pediculicides decreased with the number of head lice infestations experienced. One in three households kept children from school because of pediculosis. Other widespread misconceptions, such as that excessive cleaning is necessary to fight head lice, may also add unnecessary burden to households. School affiliation had a significant effect on checking frequency and method, knowledge and willingness to inform others about own pediculosis. CONCLUSIONS: Increased checking frequencies appear to be the most important element to reduce head lice prevalence in Norway and should be a primary focus of future strategies. National campaigns directed through schools to individual households, might be an important tool to achieve this goal. In addition to improving actions taken, such campaigns should also provide accurate information to reduce costs and enhance the level of knowledge about head lice in households.

Head lice and the use of spinosad.

BACKGROUND: Head lice infestations are responsible for social and economic distress. Despite a reported increase in resistance, permethrin 1% is still the first-line treatment of head lice. Alternative topical pediculicidal agents include malathion and benzyl alcohol, but resistance is of growing concern. In 2011, a new pediculicide, spinosad, was introduced. OBJECTIVE: Our aim was to review the clinical pharmacology, efficacy, tolerability, and current place in therapy of spinosad for the treatment of head lice. METHODS: Pertinent articles and abstracts were identified through searches of MEDLINE/Ebsco and MEDLINE/Ovid from 1948 to September 2011 and International Pharmaceutical Abstracts from 1966 to September 2011. RESULTS: Two reports described 3 trials of spinosad used for the treatment of head lice. One study (n = 120) demonstrated efficacy of both spinosad 0.5% and spinosad 1% compared with placebo, with 82.5% and 86.1% of patients free of live lice 14 days after treatment, respectively, compared with 25.6% in the placebo group (P < 0.001 for each treatment). The difference between the spinosad 0.5% and 1% treatment groups was not significant. Two trials (n = 1038) comparing spinosad 0.9% with permethrin 1% reported greater efficacy for spinosad with absence of live lice 14 days after 1 or 2 treatments for 84.6% and 86.7%, respectively, of primary cases compared with 44.9% and 42.9% with permethrin (P < 0.001 for both studies). The most common reported adverse events were eye and scalp irritation, but they were not statistically significant (P = 0.329 and P = 0.395, respectively). Only application-site erythema reactions showed statistical significance, with 6.8% in the permethrin group versus 3.1% in the spinosad group (P = 0.007). CONCLUSIONS: Although limited, the available literature suggests that spinosad is an effective and well-tolerated agent for the treatment of head lice. In a time of increasing resistance, spinosad has demonstrated superior performance compared with permethrin. A review of the literature did not identify any studies comparing spinosad to benzyl alcohol 5% or malathion 0.5%.

Head lice treatments and school policies in the US in an era of emerging resistance: a cost-effectiveness analysis.

BACKGROUND: Head lice are a common infection in school-age children worldwide. Several authorities in the US have recommended different treatments and school policies in order to control this disease. Recent concerns of emerging lice resistance worldwide raise the necessity to reassess the current recommendations. OBJECTIVES: To perform a cost-effectiveness analysis (from the US caregiver perspective) of three head lice treatments commonly used in the US, permethrin 1%, malathion 0.5% and the lice comb, in order to evaluate the cost effectiveness of different treatments in the current era, and to explore the effect of different factors in this analysis. METHODS: We used a decision-tree model to represent the costs and effectiveness of the different treatment strategies. A patient/caregiver perspective was applied, with a time horizon of 2 weeks. Probabilities of treatment success or failure of the three treatments were based on the literature. Effectiveness was measured as the successful eradication of head lice, and costs - including the costs of the treatment, the physician co-pay and the costs of days out of school - were calculated. One-way and multi-way analyses were performed using decision analysis software (Treeage Pro Healthcare 2008). RESULTS: Combing was dominated by permethrin 1%. The incremental cost-effectiveness ratio of malathion 0.5% versus permethrin 1% was $US161.75 per cure. For caregivers whose willingness to pay is <$US161.75 per cure, permethrin 1% is the most cost-effective option. For those with a willingness to pay of > or =$US161.75 per cure malathion 1% may offer the highest net monetary benefit. Twenty percent of the uncertainty in the model is due to variation in permethrin 1% resistance, and approximately 73% of the total variability of the model is attributed to the number of days the student has to be out of school because of the school's policy. CONCLUSIONS: Our study suggests that permethrin 1% was the most cost-effective treatment for those with a willingness to pay of <$US162 per cure. Sensitivity of lice to permethrin and the specific school head lice policy had major effects on the model. Thus, informing communities in a given geographical area about the degree of head lice resistance and sensitivity is necessary in order for the public to make a rational decision regarding treatment. Schools' head lice policies have a major effect on the cost of head lice treatments.

Does dimeticone clear head lice?

Head lice infestation is common and mainly affects children of primary school age. Treatments include licensed topical preparations containing conventional chemical insecticides and medical devices. Each of these fail to eradicate head lice in some patients and resistance is a problem with chemical insecticides. Dimeticone 4% lotion (Hedrin - Thornton & Ross) is a new treatment licensed "for the eradication of head lice infestations". Here we consider its place in the context of other options.

What parents in Australia know and do about head lice.

INTRODUCTION: Although parents in developed market economies regard head lice infections (pediculosis) as a significant problem, health departments generally rate pediculosis as a low priority health issue, encouraging parents to manage and control it. But how well equipped and willing are parents to manage the infections? There do not appear to be any studies in the literature addressing these issues. This article presents the results of a survey conducted in Australia that aimed to answer these questions. METHODS: A cross-sectional survey of parents of primary school aged children in Victoria (Vic) and north Queensland (NQ) was conducted using a self-administered questionnaire. The study investigated the knowledge, attitudes and practices of parents regarding head lice infections. RESULTS: Only 7.1% of 1338 who completed the questionnaire answered all 10 knowledge questions correctly and more than one-third failed to answer half correctly. There was a weak negative correlation between parents' knowledge and the prevalence of active pediculosis in the school. Almost all parents wanted the responsibility for treating pediculosis and more than three-quarters saw it as a health concern. A higher proportion of parents in NQ used preventative strategies (67% vs 41%). Most parents spent less than AU$50 per year on treatments. Alarmingly, however, the proportion of children missing school as a result of pediculosis was 24.4% and 30.3% in Vic and NQ, respectively. In Vic there was a positive correlation (r = 0.39) between missing school in the previous 12 months and prevalence of pediculosis in the school. CONCLUSIONS: This appears to be the most comprehensive study of parental knowledge, beliefs, and practices regarding head lice infections. Although parents wanted responsibility for the management of pediculosis, deficiencies in their knowledge indicate they may be inadequately equipped to do so. Given the high proportion of children in both states who have missed school as a result of head lice, it is recommended that health departments in Australia should work to ensure that consistent and accurate messages about pediculosis are disseminated, and that relevant legislation is amended to prevent children being excluded from school.

Head louse infestations: the "no nit" policy and its consequences.

Health authorities in the USA, Canada and Australia recommend a "no nit" policy, i.e. the immediate dismissal of all children who have head lice, eggs and/or nits on their hair from school, camp or child-care settings. These children would be readmitted to the institution only when all head lice, eggs and nits have been removed. The "no nit" policy assumes that all nits seen when examining the scalp are viable and therefore the infested individual should be treated for lice, and all nits must be removed from the scalp. However, it has been repeatedly shown that only a small number of children who have nits on their scalp are also infested with living lice. Accordingly, in the USA alone 4-8 million children are treated unnecessarily for head lice annually, which amounts to 64% of all lice treatments. In addition, 12-24 million school days are lost annually. The annual economic loss owing to missed workdays by parents who have to stay home with their children adds US$4-8 billion to the country's economy. The policy also results in serious psychological problems for children and their parents. Therefore, the "no nit" policy should be abandoned and alternative ways of examination and treatment for head lice should be found.

Head lice treatment costs and the impact on managed care.

The number of head lice infestations occurring annually in the United States is estimated at 6 million to 12 million. Although a formal economic analysis of head lice treatments has not been conducted, the direct cost of treatment can be roughly estimated by considering the costs of pediculicides and taking into consideration that patients may self-treat up to 5 times before seeking medical care. Added to the direct costs of treatment are indirect costs because of lost school days and lost productivity and wages of parents who must stay home to care for children who are sent home from schools that employ no-nit policies. The cost of head lice infestation is tied to diagnostic and treatment practices. Research suggests that head lice infestations are frequently misdiagnosed. In addition, over-the-counter treatments are often used incorrectly. The combination of misdiagnosis and improper treatment has contributed to decreased efficacy of pediculicides. This, in turn, further contributes to ineffective treatment and the necessity for retreatment and related increases in costs. Lindane, a prescription pediculicide, is associated with serious safety concerns and is now recommended for use in selected populations only when conventional treatment fails. Malathion 0.5% is the only prescription pediculicide that is considered to be safe and effective with no decrease in efficacy over time. Managed care organizations, in collaboration with school nurses and other healthcare providers, are working to promote more accurate diagnosis and proper use of pediculicides. The objectives of these efforts are to make the treatment of head lice more effective and ultimately to lower the cost of treatment by introducing better options early on.

Economic considerations associated with Pediculus humanus capitis infestation.

An estimated 6 to 12 million head lice infestations occur in the United States annually, with children ages 3 to 12 most likely to be affected. There are significant direct costs associated with treatment and indirect costs due to lost time from school. Anecdotal reports suggest that direct costs of treatment are in the hundreds of millions of dollars annually. Indirect costs are also substantial but more difficult to quantify. Examples of indirect costs include missed days from schools that use a "no nit" policy, lost wages for parents who must stay home with children, and costs of daycare for parents who cannot miss work. Contributors to the expense of treating head lice include misdiagnosis, and, consequently unneeded treatment; treatment failure due to misuse of pediculicides or other agents; and developing resistance, particularly to over-the-counter pyrethroid agents. An overview of direct and indirect costs of infestation are included in this review, along with a discussion of factors that lead to misuse and overuse of pediculicides. More accurate diagnosis of head lice infestation may provide the most effective means of controlling the costs of care and ensuring proper use of pediculicides.

Prevalence, risk factors and economic importance of infestations with Sarcoptes scabiei and Haematopinus suis in sows of pig breeding farms in Hesse, Germany.

A cross-sectional survey was performed in 110 randomly selected pig-breeding farms of southern Hesse, Germany to estimate the prevalence of ectoparasite infestations and to find possible risk factors. Ear scrapings of, if available, 10 sows per farm were examined for Sarcoptes scabiei var. suis (De Geer) (Acaridida: Sarcoptidae) by the potassium hydroxide digestion method, and a total of 2754 sows was inspected for skin lesions and infestations with Haematopinus suis (L.) (Anoplurida: Haematopinidae). Data on farm profiles and sows were collected by a questionnaire. In total, 19.1% and 2.5% of the sows were found to be infested with S. scabiei or H. suis, respectively. The percentage of mite or louse infestation was significantly higher in sows showing pruritus than in those without skin lesions. Both ectoparasite infestations were related neither to the age of sows nor their reproduction status, nor to the time interval to last ectoparasite treatment. Using farms as the unit of analysis, the estimated prevalence of mange mite and louse infestations was 45.4% and 14.5%, respectively. There was no significant association between the presence of S. scabiei and H. suis in the farms. Risk factors for S. scabiei infestation were mixed housing of dry and nursing sows in the same unit (vs. separate housing) and straw bedding (vs. strawless). For louse infestation, only mechanical cleaning of stable units (vs. additional use of disinfection methods) and pasturing of gilts and dry sows were identified as risk factors. The economic loss by S. scabiei infestation in the study population was assessed at euro 4200 per affected farm and year on average.

[The importance of different pig diseases in the Netherlands]. / Het belang van de verschillende varkensziekten in Nederland.

As part of the project 'Clean pigs', IPG Institute for Pig Genetics BV made an inventory of the impact of different diseases on the Dutch pig industry. An expert panel assessed the importance of the different diseases with regard to public health, farm economy, the pig sector and export sales. The possibilities for the diagnosis of the different pathogens were listed and the goal for the next years, was set. Diseases were classified into three categories, according to their importance for the Dutch pig industry (Table 2). The diseases that can be eradicated are Salmonella (only specific strains), Pasteurella multocida DNT + PAR), Actinobacillus pleuropneumoniae, Haematopinus suis (lice) and Sarcoptes scabei (var. suis) (mange). National introduction of list A en most list B diseases of the OIE classification must be prevented.

Head lice: changing the expensive chemotherapy culture.

The revulsion prompted by the discovery of head lice on a child's head, and the money spent by the NHS each year on supplying licensed medicines for head lice, is disproportionate to the medical impact that lice have on their hosts. This article discusses the evidence available on the effectiveness of the commonest parasiticidal preparations, and argues the case for a more rational, simpler and cost-effective response to this common problem.

[The influence of skin parasite infection on the productivity of gilts at pig testing stations]. / Wplyw zarazenia pasozytami skóry na produkcyjnosc loszek uzyskiwana w stacjach kontroli skurtch.

On the basis of skin scrapings collected together with cerumen from the inside of ears, the occurrence of a hidden mite and louse infection was assessed to evaluate its effect on the productive traits of gilts fattened during 1996-1997 at Pig Testing Stations (PTS). The productivity was highly influenced by the station factors. The low level of infection had, however, some negative effect in a few cases, and in few it was not clear, probably due to the phenomenon of resilience.

Diversity of ectoparasites in sheep flocks in São Paulo, Brazil.

The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of São Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the 'Associação Paulista de Criadores de Ovinos' (ASPACO; São Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.

Effects of parasitic infestation on the productivity of alpacas (Lama pacos).

A trial was carried out in alpacas (Lama pacos) to determine the economic benefit of controlling both external and internal parasites using ivermectin (Ivomec, Merck, Sharpe and Dohme). After four months the treated male alpacas had gained on average 3.1 kg more than the untreated males and their fleece weighed 0.36 kg more. Treated females gained 1.9 kg more than the controls but their fleece weighed 0.03 kg less. This resulted in a net financial benefit to the farmer of US$3.54 for each male alpaca and US$1.36 for each female.