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Sample records for lice pediculus capitis

  1. Repellency against head lice (Pediculus humanus capitis).

    PubMed

    Semmler, Margit; Abdel-Ghaffar, Fathy; Al-Rasheid, Khaled; Klimpel, Sven; Mehlhorn, Heinz

    2010-02-01

    The head louse problem increases at all levels of the international societies due to activities or life conditions that lead to often hair contacts among people. Lice occur exclusively on humans. Thus, they avoid dropping down from a head and therefore accept even a bad smelling hair of new a host. Due to this behaviour, there are only a few products on the markets which dare to claim a repellency activity that protects humans from infestation with head lice. The present study shows that a combination of an extract of the seeds of the plant Vitex agnus castus (monk pepper) and the compound paramenthan-3,8-diol (which is also found in some plants, e.g. Eucalyptus) act synergistically and are able to protect human hair for at least 7 h from invasion of head lice (Pediculus humanus capitis). The recently developed product containing both compounds is named Licatack Preventive Spray. PMID:20054562

  2. Pediculus humanus capitis (head lice) and Pediculus humanus humanus (body lice): response to laboratory temperature and humidity and susceptibility to monoterpenoids.

    PubMed

    Gallardo, A; Mougabure Cueto, G; Picollo, M I

    2009-07-01

    Human pediculosis is produced by Pediculus humanus humanus (Linnaeus 1758) and Pediculus humanus capitis (De Geer 1767). Laboratory-reared body lice, susceptible to insecticides, were used as reference in toxicological studies on head lice. In this work, we evaluated the survival of both subspecies at different temperatures and relative humidities and we propose the optimal conditions for comparative bioassays. Moreover, we used these conditions to test the activity of three monoterpenoids against both lice. The results showed differential response to changes in temperature and humidity between both organisms. The survival of body lice ranged between 83% and 100% and was not affected for the tested conditions. The survival of head lice depended on temperature, humidity, and exposure time. The optimal conditions for head lice were 18 masculineC and 97% relative humidity at 18 h of exposition. The insecticidal activity of three monoterpenoids (pulegone, linalool, and 1,8-cineole), evaluated according the selected conditions by topical application, showed no significant differences between males of body and head lice. To conclude, as head lice required more special laboratory conditions than body lice, the optimal head lice conditions should be used in both organisms in comparative bioassays. Body louse is an appropriate organism for testing products against of head louse. PMID:19242723

  3. Bioactivity of Argentinean essential oils against permethrin-resistant head lice, Pediculus humanus capitis.

    PubMed

    Toloza, Ariel C; Zygadlo, Julio; Biurrun, Fernando; Rotman, Alicia; Picollo, María I

    2010-01-01

    Infestation with the head louse, Pediculus humanus capitis De Geer (Phthiraptera: Pediculidae), is one of the most common parasitic infestation of humans worldwide. Traditionally, the main treatment for control of head lice is chemical control that is based in a wide variety of neurotoxic synthetic insecticides. The repeated overuse of these products has resulted in the selection of resistant populations of head lice. Thus, plant-derived insecticides, such as the essential oils seem to be good viable alternatives as some have low toxicity to mammals and are biodegradable. We determined the insecticidal activity of 25 essential oils belonging to several botanical families present in Argentina against permethrin-resistant head lice. Significant differences in fumigant activity against head lice were found among the essential oils from the native and exotic plant species. The most effective essential oils were Cinnamomum porphyrium, followed by Aloysia citriodora (chemotype 2) and Myrcianthes pseudomato, with KT(50) values of 1.12, 3.02 and 4.09; respectively. The results indicate that these essential oils are effective and could be incorporated into pediculicide formulations to control head lice infestations once proper formulation and toxicological tests are performed. PMID:21062140

  4. Bioactivity of Argentinean Essential Oils Against Permethrin-Resistant Head Lice, Pediculus humanus capitis

    PubMed Central

    Toloza, Ariel C; Zygadlo, Julio; Biurrun, Fernando; Rotman, Alicia; Picollo, María I

    2010-01-01

    Infestation with the head louse, Pediculus humanus capitis De Geer (Phthiraptera: Pediculidae), is one of the most common parasitic infestation of humans worldwide. Traditionally, the main treatment for control of head lice is chemical control that is based in a wide variety of neurotoxic synthetic insecticides. The repeated overuse of these products has resulted in the selection of resistant populations of head lice. Thus, plant-derived insecticides, such as the essential oils seem to be good viable alternatives as some have low toxicity to mammals and are biodegradable. We determined the insecticidal activity of 25 essential oils belonging to several botanical families present in Argentina against permethrin-resistant head lice. Significant differences in fumigant activity against head lice were found among the essential oils from the native and exotic plant species. The most effective essential oils were Cinnamomum porphyrium, followed by Aloysia citriodora (chemotype 2) and Myrcianthes pseudomato, with KT50 values of 1.12, 3.02 and 4.09; respectively. The results indicate that these essential oils are effective and could be incorporated into pediculicide formulations to control head lice infestations once proper formulation and toxicological tests are performed. PMID:21062140

  5. Ovicidal and adulticidal effects of monoterpenoids against permethrin-resistant human head lice, Pediculus humanus capitis.

    PubMed

    Toloza, A C; Vassena, C; Picollo, M I

    2008-12-01

    The improper use of pediculicides containing permethrin has led to the development of resistance. Thus, new alternatives for control are needed. Plant-derived insecticides are attractive alternatives to common chemical insecticides because most of them are environmentally friendly and non-toxic to mammals. The toxic activity of 23 monoterpenoids belonging to several chemical classes was tested against the eggs of permethrin-resistant head lice, Pediculus humanus capitis De Geer (Phthiraptera: Pediculidae). Significant differences in ovicidal action were observed among the tested substances. The most effective chemicals were hydrocarbons and ethers, followed by ketones, alcohols, phenols and esters. A linear relationship between egg mortality and knockdown time (KT(50)) on adults by the tested components revealed that most of the components were effective on both egg and adult stages. The monoterpenoids described herein are good candidates as effective pediculicides. PMID:19120961

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

    PubMed

    Ketzis, Jennifer K; Clements, Kathleen; Honraet, Kris

    2014-05-01

    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. PMID:24647985

  7. Effectiveness of isopropyl myristate/cyclomethicone D5 solution of removing cuticular hydrocarbons from human head lice (Pediculus humanus capitis)

    PubMed Central

    2012-01-01

    Background In the treatment of human head lice infestation, healthcare providers are increasingly concerned about lice becoming resistant to existing pesticide treatments. Traditional pesticides, used to control these pests, have a neurological mechanism of action. This publication describes a topical solution with a non-traditional mechanism of action, based on physical disruption of the wax layer that covers the cuticle of the louse exoskeleton. This topical solution has been shown clinically to cure 82% of patients with only a 10-minute treatment time, repeated once after 7 days. All insects, including human head lice, have a wax-covered exoskeleton. This wax, composed of hydrocarbons, provides the insect with protection against water loss and is therefore critical to its survival. When the protective wax is disrupted, water loss becomes uncontrollable and irreversible, leading to dehydration and death. A specific pattern of hydrocarbons has been found in all of the head louse cuticular wax studied. Iso-octane effectively removes these hydrocarbons from human head lice’s cuticular wax. Methods A method of head louse cuticle wax extraction and analysis by gas chromatography was developed. Human head lice (Pediculus humanus capitis) were collected from infested patients and subjected to any of three extraction solvents comprising either the test product or one of two solvents introduced as controls. A gas chromatograph equipped with a flame ionization detector (GC/FID) was used to determine the presence of hydrocarbons in the three head lice extracts. Results In the study reported herein, the test product isopropyl myristate/cyclomethicone D5 (IPM/D5) was shown to perform comparably with iso-octane, effectively extracting the target hydrocarbons from the cuticular wax that coats the human head louse exoskeleton. Conclusions Disruption of the integrity of the insect cuticle by removal of specific hydrocarbons found in the cuticular wax appears to offer a

  8. Comparative efficacy of commercial combs in removing head lice (Pediculus humanus capitis) (Phthiraptera: Pediculidae).

    PubMed

    Gallardo, Anabella; Toloza, Ariel; Vassena, Claudia; Picollo, María Inés; Mougabure-Cueto, Gastón

    2013-03-01

    The use of a fine comb for removing lice from the head of the human host is a relevant tool both in the diagnosis of infestations and as part of an integrated control strategy of head lice. The effectiveness of a fine comb depends, in part, on the design and material they are built. The aim of this study was to compare in vivo the efficacy of metal and plastic combs that are currently used in the removal of head lice and eggs worldwide. The space between comb teeth and the length was 0.23 and 13 mm in KSL® plastic, 0.3 and 10.7 mm in NOPUCID® plastic, 0.15 and 31 mm in KSL® metal and 0.09 and 37 mm in ASSY® metal. The assays were performed comparing the combs in pairs: (a) KSL® vs. NOPUCID® plastic combs, (b) KSL® vs. ASSY® metal combs and (c) KSL® plastic comb vs. ASSY® metal comb. The most effective plastic comb was KSL®, removing a higher number of individuals of all stages. The most effective metal comb was ASSY®, removing more insects of all stages (except adults). The comparative test between KSL® plastic and ASSY® metal showed that ASSY® was the most effective in removing head lice and their eggs. PMID:23212391

  9. Comparative efficacy of new commercial pediculicides against adults and eggs of Pediculus humanus capitis (head lice).

    PubMed

    Gallardo, Anabella; Mougabure-Cueto, Gastón; Vassena, Claudia; Picollo, María Inés; Toloza, Ariel Ceferino

    2012-05-01

    The use of pyrethroids to control head louse infestations have suffered considerable loss of efficacy due to the development of resistance. In the last past years, several new alternative products to synthetic pyrethroids have been developed and are sold in the Argentinean market against head lice. The present study investigated the efficacy of two new Argentinean products Nopucid Qubit® and Nopucid Bio Citrus® and its comparison with two reference products Nyda® and Hedrin®. Nopucid Qubit® is a two-phase lotion containing geraniol and citronellol (phase 1) and ciclopentaxiloxane (phase 2); while Nopucid Bio Citrus® contains dimethicone, ciclopentaxiloxane, and bergamot essential oil. These products are physically acting compounds. The sensitivity of two laboratory assays for testing insecticide activity of new formulations was also compared. Mortality (100%) of motile forms occurred after they were exposed to any product for 1 and 2 min, either by in vitro or ex vivo test. Concerning ovicidal activity, the most effective pediculicides were Nopucid Bio Citrus® and Nyda®, followed by Hedrin® and Nopucid Qubit®. The present study revealed, for the first time, the efficacy of over-the-counter commercial pediculicides available in Argentine (Nopucid Bio Citrus® and Nopucid Qubit®) on either motile stages or eggs against head lice. PMID:21984369

  10. Treatment of head lice (Pediculus humanus capitis) infestation: is regular combing alone with a special detection comb effective at all levels?

    PubMed

    Kurt, Özgür; Balcıoğlu, I Cüneyt; Limoncu, M Emin; Girginkardeşler, Nogay; Arserim, Süha K; Görgün, Serhan; Oyur, Tuba; Karakuş, Mehmet; Düzyol, Didem; Gökmen, Aysegül Aksoy; Kitapçıoğlu, Gül; Özbel, Yusuf

    2015-04-01

    Head lice infestation (HLI) caused by Pediculus humanus capitis has been a public health problem worldwide. Specially designed combs are used to identify head lice, while anti-lice products are applied on the scalp for treatment. In the present study, we aimed to test whether combing only by precision detection comb (PDC) or metal pin comb (MPC) could be effective alternatives to the use of anti-lice products in children. A total of 560 children from two rural schools in Turkey were screened. In the PDC trial, children were combed every second day for 14 days, while in the MPC trial, combing was performed once in every four days for 15 days. Children were divided into two groups (dry combing and wet combing) for both trials and results were compared. The results showed no significant differences between dry and wet combing strategies for both combs for the removal of head lice (p > 0.05). The number of adult head lice declined significantly on each subsequent combing day in both approaches, except on day 15 in the MPC trial. In the end, no louse was found in 54.1 and 48.9% of children in the PDC and MPC trials, respectively. Since family members of infested children were not available, they were not checked for HLI. Four times combing within 2 weeks with MPC combs was found effective for both treatment of low HLI and prevention of heavy HLI. In conclusion, regular combing by special combs decreases HLI level in children and is safely applicable as long-term treatment. PMID:25604670

  11. Ex vivo effectiveness of French over-the-counter products against head lice (Pediculus humanus capitis De Geer, 1778).

    PubMed

    Combescot-Lang, Catherine; Vander Stichele, Robert H; Toubate, Berthine; Veirron, Emilie; Mumcuoglu, Kosta Y

    2015-05-01

    Head lice infestation is still a public health problem worldwide, with an intracountry and intercountry prevalence variation of 0.7 to 59%. There is a large variety of over-the-counter anti-louse products, but their efficacy is not always well assessed. Our objective was to test the pediculicidal and ovicidal efficacy of 21 over-the-counter head louse products, available in France during the period of 2008 to 2012. We tested children living in Tours City in central France and visiting preschools, primary schools, kindergarten, camps, and child care facilities, as well as children in their family houses, and were examined for the presence of lice. The products were collected from randomly selected pharmacies by covert investigators and then tested in the laboratory on an ex vivo sample of head lice and their eggs, collected from the hair of infested children. Living lice and unharmed eggs were collected from the scalps of 3-12 years old. The laboratory conditions for ex vivo testing mimicked the manufacturers' instructions for exposure time and application method. In 21 runs, 3919 living lice and 4321 undamaged living eggs were collected from the scalp of over 400 children. The 21 products were classified in three groups: 6 products in a group of potentially 100% pediculicidal activity and potentially 100% ovicidal activity, 8 products in a group of potentially 100% pediculicidal activity but insufficient ovicidal activity (including 2 products with claims of single application treatment), and 7 products in a group of insufficient pediculicidal activity and ovicidal activity. The pharmaceutical market for head lice products in France is swamped with poorly tested and ineffective products. Rigorous efficacy testing preregistration and periodic screening and testing of effectiveness in the post-registration period should be endorsed by the health authorities. PMID:25716822

  12. Determination, mechanism and monitoring of knockdown resistance in permethrin-resistant human head lice, Pediculus humanus capitis.

    PubMed

    Clark, J Marshall

    2009-03-01

    Permethrin resistance has been reported worldwide and clinical failures to commercial pediculicides containing permethrin have likewise occurred. Permethrin resistance in head lice populations from the U.S. is widespread but is not yet uniform and the level of resistance is relatively low (~4-8 fold). Permethrin-resistant lice are cross-resistant to pyrethrins, PBO-synergized pyrethrins and to DDT. Nix((R)), when applied to human hair tufts following manufacture's instructions, did not provide 100% control when assessed by the hair tuft bioassay in conjunction with the in vitro rearing system. Resistance to permethrin is due to knockdown resistance (kdr), which is the result of three point mutations within the alpha-subunit gene of the voltage-gated sodium channel that causes amino acid substitutions, leading to nerve insensitivity.A three-tiered resistance monitoring system has been established based on molecular resistance detection techniques. Quantitative sequencing (QS) has been developed to predict the kdr allele frequency in head lice at a population level. The speed, simplicity and accuracy of QS made it an ideal candidate for a routine primary resistance monitoring tool to screen a large number of louse populations as an alternative to conventional bioassay. As a secondary monitoring method, real-time PASA (rtPASA) has been devised for a more precise determination of low resistance allele frequencies. To obtain more detailed information on resistance allele zygosity, as well as allele frequency, serial invasive signal amplification reaction (SISAR) has been developed as an individual genotyping method. Our approach of using three tiers of molecular resistance detection should facilitate large-scale routine resistance monitoring of permethrin resistance in head lice using field-collected samples. PMID:20161186

  13. Lice, body with stool (Pediculus humanus) (image)

    MedlinePlus

    ... capitis ), or the pubic area ( Phthirus pubis ). Some body lice may carry diseases such as epidemic typhus, relapsing fever, or trench fever. (Image courtesy of the Centers for Disease Control and ...

  14. Head Lice (Pediculosis Capitis)

    MedlinePlus

    ... Pronto®, R&C®, RID®, Triple X®) and permethrin lotion 1% (Nix®). Both medicines kill only live lice, ... than recommended. Before applying the over-the-counter lotions, do not use conditioner on the hair, as ...

  15. The fumigant and repellent activity of aliphatic lactones against Pediculus humanus capitis (Anoplura: Pediculidae).

    PubMed

    Toloza, Ariel Ceferino; Zygadlo, Julio; Mougabure-Cueto, Gastón; Zerba, Eduardo; Faillaci, Silvina; Picollo, María Inés

    2006-02-01

    New alternative insecticides are necessary for the chemical control of head lice. In this study the fumigant knockdown time 50% (KT50) and repellency index (RI) of three aliphatic lactones was compared with two essential oils and DDVP, against permethrin-resistance Pediculus humanus capitis from Argentina. In the fumigant assay, none of the lactones were effective compared to the highest activity of eucalyptus (KT50 15.53 m). In the repellency test, the three lactones were equally or more effective (RI ranging from 60.50 to 76.68) than the positive control (piperonal). These lactones are promising as head lice repellents. PMID:16699710

  16. Efficacy of herbal shampoo base on native plant against head lice (Pediculus humanus capitis De Geer, Pediculidae: Phthiraptera) in vitro and in vivo in Thailand.

    PubMed

    Soonwera, Mayura

    2014-09-01

    Head lice infestation (or pediculosis) is an important public health problem in Thailand, especially in children between the ages 5 and 11 years. Head lice resistance is increasing, chemical pediculicides have lost their efficacy, and, therefore, alternative pediculicides such as herbal shampoos have been proposed to treat head lice infestation. Thus, the present study investigated the efficacy of three herbal shampoos based on native plants in Thailand (Acorus calamus Linn., Phyllanthus emblica Linn., and Zanthoxylum limonella Alston) against head lice and compared them with carbaryl shampoo (Hafif shampoo, 0.6% w/v carbaryl), malathion shampoo (A-Lice shampoo, 1.0% w/v malathion), and commercial shampoos (Babi Mild Natural' N Mild and Johnson's baby shampoo) in order to assess their in vitro and in vivo efficacy. For in vitro study, doses of 0.12 and 0.25 ml/cm(2) of each herbal shampoo were applied to filter paper, then 10 head lice were place on the filter paper. The mortalities of head lice were recorded at 5, 15, 30, and 60 min. The results revealed that all herbal shampoo were more effective on pediculicidal activity than chemical and commercial shampoos with 100% mortality at 15 min; LT₅₀ values ranged from 0.25 to 1.90 min. Meanwhile, chemical shampoos caused 20-80% mortality, and LT₅₀ values ranged from 6.50 to 85.43 min. On the other side, commercial shampoos showed 4.0% mortality. The most effective pediculicide was Z. limonella shampoo, followed by A. calamus shampoo, P. emblica shampoo, carbaryl shampoo, malathion shampoo, and commercial shampoo, respectively. In vivo results showed that all herbal shampoos were also more effective for head lice treatment than chemical and commercial shampoos with 94.67-97.68% of cure rate after the first treatment; the second treatment, 7 days later, revealed that the cure rate was 100%. Meanwhile, chemical shampoo showed 71.67-93.0% of cure rate and, unfortunately, commercial shampoos were nontoxic to

  17. Clinical efficacy and safety in head lice infection by Pediculus humanis capitis De Geer (Anoplura: Pediculidae) of a capillary spray containing a silicon-oil complex.

    PubMed

    Izri, A; Uzzan, B; Maigret, M; Gordon, M S; Bouges-Michel, C

    2010-12-01

    Head lice are endemic worldwide. Resistance to permethrin and doubts about the safety of pesticides promoted the use of physical therapies (wet-combing, dry-on suffocation). The aim of our study was to test the pediculicidal and ovicidal effects of one application of a silicon-oil complex composed of dimethiconol and castor oil. The study was a prospective cohort of 108 infested patients (11 males, 97 females; 58 children, 50 adults), in Sri-Lanka. Pediculicidal efficacy was evaluated as the percentage of patients free of live lice one hour after the application of the treatment and at day 1 (wet combing). Ovicidal efficacy was calculated as the proportion of subjects without larval stages at days 1 and 7 among subjects followed up all over the study. In normal conditions of use, in this open cohort, a pediculicidal effect of a dimethiconol-castor-oil lotion was.shown one hour after application in 99/108 (91.7%) treated subjects and at day 1 in 86/99 (87%) subjects and an ovicidal effect at day 7 in 79/108 (73.2%) treated subjects. A second application of the same product was necessary to increase the cure rate to 79.6% (86/108) at day 8. In our study, the second application of the same product was performed seven days later, but the best time for additional applications should be defined in further studies. However, the efficacy of this safe physical treatment was similar to that of chemical pediculicides (malathion, permethrin). PMID:21275239

  18. The prevalence of pediculus capitis among the middle schoolchildren in Fars Province, southern Iran

    PubMed Central

    Davarpanah, Mohammad Ali; Rasekhi Kazerouni, Akbar; Rahmati, Hashem; Neirami, Roxana Neirami; Bakhtiary, Hamid; Sadeghi, Mohammad

    2013-01-01

    Background: Pediculosis capitis is a common parasitic infection of children. In this study we assessed the prevalence of head pediculosis among the middle schoolchildren in the urban and rural areas of Fars province, southern Iran. Methods: All middle schoolchildren ages 11-14, in all the urban and rural areas of the province were screened for head lice infestation by examining their hair and scalp. The parents of the infested children were also examined. The study was repeated in the different seasons in the same areas. Moreover, the infested children were treated with permethrin shampoo and re-examined one week later for any relapse. Results: The general prevalence of head lice infestation in middle school students was 0.23% in autumn, 0.27% in winter and 0.11% in spring. In all three seasons, pediculosis capitis prevalence was higher among females and in the rural areas. Treatment with permethrin shampoo was markedly more successful in males from both regions in all months except the urban areas in spring. Conclusion: The results show that pediculus capitis is generally uncommon among Fars Province middle schoolchildren. It is needed that health providers promote heath education programs especially in the rural areas. PMID:24009945

  19. Effect of Environmental Conditions and Toxic Compounds on the Locomotor Activity of Pediculus humanus capitis (Phthiraptera: Pediculidae).

    PubMed

    Ortega-Insaurralde, I; Toloza, A C; Gonzalez-Audino, P; Mougabure-Cueto, G A; Alvarez-Costa, A; Roca-Acevedo, G; Picollo, M I

    2015-09-01

    In this work, we evaluated the effect of environmental variables such as temperature, humidity, and light on the locomotor activity of Pediculus humanus capitis. In addition, we used selected conditions of temperature, humidity, and light to study the effects of cypermethrin and N,N-diethyl-3-methylbenzamide (DEET) on the locomotor activity of head lice. Head lice increased their locomotor activity in an arena at 30°C compared with activity at 20°C. When we tested the influence of the humidity level, the locomotor activity of head lice showed no significant differences related to humidity level, both at 30°C and 20°C. Concerning light influence, we observed that the higher the intensity of light, the slower the movement of head lice. We also demonstrated that sublethal doses of toxics may alter locomotor activity in adults of head lice. Sublethal doses of cypermethrin induced hyperactivated responses in adult head lice. Sublethal doses of DEET evocated hypoactivated responses in head lice. The observation of stereotyped behavior in head lice elicited by toxic compounds proved that measuring locomotor activity in an experimental set-up where environmental conditions are controlled would be appropriate to evaluate compounds of biological importance, such as molecules involved in the host-parasite interaction and intraspecific relationships. PMID:26336260

  20. Prevalence of Pediculus humanus capitis infestation among kindergarten children in Bahía Blanca city, Argentina.

    PubMed

    Gutiérrez, María Mercedes; González, Jorge Werdin; Stefanazzi, Natalia; Serralunga, Gabriela; Yañez, Loreto; Ferrero, Adriana Alicia

    2012-09-01

    The human head louse, Pediculus humanus capitis De Geer (Anoplura: Pediculidae), is a worldwide public health concern. This human obligate ectoparasite usually infests school age children. The aim of this work was to investigate the prevalence of head lice in kindergarten children from Bahia Blanca. In addition, the influence of risk factors for pediculosis infestation, such as gender, hair characteristics, and socioeconomic class, was studied in relation to the prevalence of this ectoparasite. From a total of 220 pupils examined (125 girls and 95 boys), 94 showed pediculosis. The overall prevalence of head lice infestation was 42.7 %. Pediculosis was more frequent in girls (53.6 %) than in boys (28.4 %) and in medium, long, and very long hairs. No differences were found between socioeconomic classes. This indicated that head lice are relatively common in kindergarten children from Bahía Blanca. PMID:22752696

  1. The potential application of plant essential oils to control Pediculus humanus capitis (Anoplura: Pediculidae).

    PubMed

    Gutiérrez, María Mercedes; Werdin-González, Jorge Omar; Stefanazzi, Natalia; Bras, Cristina; Ferrero, Adriana Alicia

    2016-02-01

    The human head louse, Pediculus humanus capitis (Anoplura: Pediculidae), is an ectoparasite confined to the scalp and human hairs. The repeated use of insecticides for the control of head lice during past decades has resulted in the development of marked levels of resistance. Natural compounds such as essential oils (EOs) have been suggested as alternative sources for insect control agents. In order to introduce a new pediculicide based on EOs, the effectiveness of the product and their effects on human being must be analyzed. In consequence, the biological activity of EOs from the leaves and fruits of Schinus areira (Anacardiaceae) and the leaves of Thymus vulgaris (Lamiaceae), Aloysia polystachya and Aloysia citriodora (Verbenacea) were evaluated against the eggs and adults of P. humanus capitis by fumigant and contact toxicity bioassays. Additionally, dermal corrosion/irritation tests were performed on New Zealand albino rabbits. In a fumigant bioassay, EOs from the leaves and fruits of S. areira were the most toxic against P. humanus capitis adults while these EOs and T. vulgaris were the most effective against the eggs. In contact bioassay, the EO from T. vulgaris was the most toxic against both stages. In the corrosion/irritation tests, the EOs did not produce dermal effects. According to the results, the essential oils from the leaves of T. vulgaris would be a valid tool for the management of P. humanus capitis. This EO produces a high knockdown effect in adults (followed by mortality) and toxicity in the eggs when it is applied for 21 min at a low concentration. PMID:26462802

  2. Epidemiological and Clinical Study of Infested Cases with Pediculus capitis and P. corporis in Khorasan-e-Razavi, Iran

    PubMed Central

    Riabi, H Ramezani Awal; Atarodi, AR

    2012-01-01

    Background Pediculosis (head lice) is considered as one of the most common health problems of the students in primary schools. The purpose of this study was to survey the prevalence rate of the infestation in the schools of Gonabad City (south of Khorasan-e-Razavi Province) to prevent its outbreak by on-time planning. Methods In this retrospective-descriptive study, data were collected from the files of recorded health examinations of 55,997 female and male students of Gonabad City. We surveyed the infested cases to Pediculus capitis and P. corporis during 2006-2010. We used schools health unit of the city health center and review reports of infestation to head lice and body lice in cumulative centers. Results The reports showed 398 cases of P. capitis and 3 P. corporis infestations, which 91.5% were female (P <0.05). Generally 46.4% were from rural and 63.6% were from urban areas (P <0.05). 71.3% of the infestation to head lice was from the last month and the rest had recently been infested. The most age group being infested were students of 6-10 years old and the lowest were >17 yr. Conclusion Pediculosis infestation has become a major health problem in primary school students in south of Khorasan-e-Razavi. PMID:23133477

  3. Nuclear genetic diversity in human lice (Pediculus humanus) reveals continental differences and high inbreeding among worldwide populations.

    PubMed

    Ascunce, Marina S; Toups, Melissa A; Kassu, Gebreyes; Fane, Jackie; Scholl, Katlyn; Reed, David L

    2013-01-01

    Understanding the evolution of parasites is important to both basic and applied evolutionary biology. Knowledge of the genetic structure of parasite populations is critical for our ability to predict how an infection can spread through a host population and for the design of effective control methods. However, very little is known about the genetic structure of most human parasites, including the human louse (Pediculus humanus). This species is composed of two ecotypes: the head louse (Pediculus humanus capitis De Geer), and the clothing (body) louse (Pediculus humanus humanus Linnaeus). Hundreds of millions of head louse infestations affect children every year, and this number is on the rise, in part because of increased resistance to insecticides. Clothing lice affect mostly homeless and refugee-camp populations and although they are less prevalent than head lice, the medical consequences are more severe because they vector deadly bacterial pathogens. In this study we present the first assessment of the genetic structure of human louse populations by analyzing the nuclear genetic variation at 15 newly developed microsatellite loci in 93 human lice from 11 sites in four world regions. Both ecotypes showed heterozygote deficits relative to Hardy-Weinberg equilibrium and high inbreeding values, an expected pattern given their parasitic life history. Bayesian clustering analyses assigned lice to four distinct genetic clusters that were geographically structured. The low levels of gene flow among louse populations suggested that the evolution of insecticide resistance in lice would most likely be affected by local selection pressures, underscoring the importance of tailoring control strategies to population-specific genetic makeup and evolutionary history. Our panel of microsatellite markers provides powerful data to investigate not only ecological and evolutionary processes in lice, but also those in their human hosts because of the long-term coevolutionary

  4. Nuclear Genetic Diversity in Human Lice (Pediculus humanus) Reveals Continental Differences and High Inbreeding among Worldwide Populations

    PubMed Central

    Ascunce, Marina S.; Toups, Melissa A.; Kassu, Gebreyes; Fane, Jackie; Scholl, Katlyn; Reed, David L.

    2013-01-01

    Understanding the evolution of parasites is important to both basic and applied evolutionary biology. Knowledge of the genetic structure of parasite populations is critical for our ability to predict how an infection can spread through a host population and for the design of effective control methods. However, very little is known about the genetic structure of most human parasites, including the human louse (Pediculus humanus). This species is composed of two ecotypes: the head louse (Pediculus humanus capitis De Geer), and the clothing (body) louse (Pediculus humanus humanus Linnaeus). Hundreds of millions of head louse infestations affect children every year, and this number is on the rise, in part because of increased resistance to insecticides. Clothing lice affect mostly homeless and refugee-camp populations and although they are less prevalent than head lice, the medical consequences are more severe because they vector deadly bacterial pathogens. In this study we present the first assessment of the genetic structure of human louse populations by analyzing the nuclear genetic variation at 15 newly developed microsatellite loci in 93 human lice from 11 sites in four world regions. Both ecotypes showed heterozygote deficits relative to Hardy–Weinberg equilibrium and high inbreeding values, an expected pattern given their parasitic life history. Bayesian clustering analyses assigned lice to four distinct genetic clusters that were geographically structured. The low levels of gene flow among louse populations suggested that the evolution of insecticide resistance in lice would most likely be affected by local selection pressures, underscoring the importance of tailoring control strategies to population-specific genetic makeup and evolutionary history. Our panel of microsatellite markers provides powerful data to investigate not only ecological and evolutionary processes in lice, but also those in their human hosts because of the long-term coevolutionary

  5. Eucalyptus essential oil toxicity against permethrin-resistant Pediculus humanus capitis (Phthiraptera: Pediculidae).

    PubMed

    Toloza, Ariel C; Lucía, Alejandro; Zerba, Eduardo; Masuh, Hector; Picollo, María Inés

    2010-01-01

    During the past decades, chemical control against the head louse Pediculus humanus capitis De Geer has been based in the application of products containing permethrin. The repetitive overuse of pediculicides has resulted in the development of high levels of resistance to one or more of these products worldwide. Essential oils obtained from aromatic plants like Eucalyptus are good and safe alternatives due to their low toxicity to mammals and easy biodegradability. In the present study, we reported the chemical composition of Eucalyptus dunnii and Eucalyptus gunni, and the fumigant activity of five Eucalyptus essential oils and their main compounds against permethrin-resistant head lice from Argentina. The most effective essential oils were Eucalyptus sideroxylon, Eucalyptus globulus ssp globulus, and Eucalyptus globulus ssp maidenii, with knockdown time 50% (KT(50)) values of 24.75, 27.73, and 31.39 min. A linear regression analysis between percentage of 1,8-Cineole and KT(50) values of the essential oils showed a significant correlation at a p < 0.01. Since Eucalyptus essential oils showed to be effective against head lice and are classified as safer compounds, they can be employed into pediculicide formulations. PMID:19902249

  6. Epidemiology of Pediculus humanus capitis infestation in Malaysian school children.

    PubMed

    Sinniah, B; Sinniah, D; Rajeswari, B

    1981-05-01

    A survey of 308,101 primary school children in Peninsular Malaysia conducted in 1979 by the School Health Services, Ministry of Health, Malaysia, revealed that 10.7% of children were infested with Pediculus humanus capitis. The prevalence rate was higher in the economically less advanced states of Terenganu (34%), Kelantan (23%), and Perlis (21%) than in the other states (4-13%). Of 14,233 school children examined in the State of Melaka, 26% of Indians, 18.7% of Malays, 6.1% of Europeans, and 0.7% of Chinese had pediculosis. The prevalence rate, which has remained unchanged over the past 5 years, does not appear to vary with age but is higher in children with long hair and those from the lower socioeconomic groups. Boys have a lower infestation rate than do girls. The higher incidence in Indians and Malays correlates well with their lower socioeconomic status in the community, and their cultural habit of maintaining longer hair than do the Chinese. The difference become less apparent in the higher socioeconomic groups. PMID:7258487

  7. Evidence of pyrethroid resistance in eggs of Pediculus humanus capitis (Phthiraptera: Pediculidae) from Argentina.

    PubMed

    Cueto, Gastón Mougabure; Zerba, Eduardo Nicolás; Picollo, María Inés

    2008-07-01

    Insecticide resistance in Pediculus humanus capitis De Geer 1778 (Phthiraptera: Pediculidae) from different countries has been well documented in the last years. Otherwise, little research has been reported about insecticide resistance in insect embryos and none in human louse embryos. In this work, we studied insecticide resistance in eggs of three head lice populations whose pyrethroid resistance was shown in adults and nymphs compared with a susceptible laboratory body louse strain. All head louse populations showed high permethrin resistance in eggs. Levels of permethrin resistance (LCRs) assessed in eggs by immersion technique were higher than those previously reported for the corresponding populations of adults by topical application. Comparison of LCR values for different populations showed that there was a direct relationship between the resistance levels assessed in eggs and those in adults. All permethrin-resistant eggs showed high resistance to d-phenothrin and dichloro-diphenyl-trichloroethane (DDT) and low resistance to carbaryl, which is in common with the resistance profile established for adults and nymphs. The results concerning the high resistance to pyrethroid (permethrin and d-phenothrin) and the cross-resistance to DDT and carbaryl detected in head louse eggs and adults suggested similar resistance mechanisms in eggs and adults of head louse populations from adults. PMID:18714869

  8. Increased monooxygenase activity associated with resistance to permethrin in Pediculus humanus capitis (Anoplura: Pediculidae) from Argentina.

    PubMed

    González Audino, P; Barrios, S; Vassena, C; Mougabure Cueto, G; Zerba, E; Picollo, M I

    2005-05-01

    We studied the profile of permethrin resistance in populations of head lice infesting children 6-12 yr old in schools and their homes in and around Buenos Aires, Argentina. Five permethrin-resistant populations with different levels of resistance were collected: Hogar Loyola (HL), Republica de Turquia (RT), Hogar Mitre (HM), Guardia de Honor (GH), and Ricardo Guiraldes (RG). One susceptible population, Bandera Argentina (BA), also was collected. Their level of resistance was evaluated, and results showed resistance ratios of 13 for HL, 16 for RT, 22 for HM, 61 for GH, and 69 for RG. To elucidate the possible involvement of the cytochrome P450 monooxygenase system in conferring permethrin resistance, ethoxycoumarin-O-deethylase (ECOD) activity was measured in abdomens of individual third instars and adults by using a fluorometric assay. The ECOD activity was lower in the susceptible BA population (4.7 ng per louse) than in the resistant ones (13.7 ng per louse for RG, 12.3 ng per louse for GH, 8.6 ng per louse for RT, and 8.2 ng per louse for HL). ECOD activity was significantly correlated with the level of resistance in the field populations (r = 0.97, P = 0.0009), suggesting a role for cytochrome monooxygenase P450 system in permethrin resistance by head louse, Pediculus humanus capitis De Geer. PMID:15962785

  9. In vitro pediculicidal activity of herbal shampoo base on Thai local plants against head louse (Pediculus humanus capitis De Geer).

    PubMed

    Rassami, Watcharawit; Soonwera, Mayura

    2013-04-01

    Head lice infestation, a worldwide head infestation caused Pediculus humanus capitis De Geer, is an important public health problem in Thailand. Several chemical pediculicides have lost in efficacy due to increasing resistance of lice against insecticide. Therefore, non-toxic alternative products, such as natural products from plants, e.g. plant extract pediculicides, are needed for head lice control. The aims of this study were to evaluate the potential of pediculicidal activity of herbal shampoo base on three species of Thai local plants (Accacia concinna (Willd.) DC, Averrhoa bilimbi Linn. and Tamarindus indica Linn.) against head lice and to compare them with carbaryl shampoo (Hafif shampoo®; 0.6% w/v carbaryl) and non-treatment control in order to assess their in vitro. Doses of 0.12 and 0.25 ml/cm2 of each herbal shampoo were applied to filter paper, and ten head lice were place on the filter paper. The mortalities of head lice on the filter paper were recorded at 1, 5, 10, 30 and 60 min by sterio-microscope. All herbal shampoos at 0.25 ml/cm2 were more effective pediculicide than carbaryl shampoo with 100% mortality at 5 min. The median lethal time (LT50) of all herbal shampoos at 0.25 ml/cm2 showed no significant differences over at 0.12 ml/cm2 (P<0.01). The most effective pediculicide was T. indica extract shampoo, followed by Av. bilimbi extract shampoo and Ac. concinna extract shampoo, with LT50 values<1.0 min. Our data showed that all herbal shampoos have high potential of pediculicide to head lice treatments for schoolchildren. PMID:23334727

  10. Resistance to insecticides and effect of synergists on permethrin toxicity in Pediculus capitis (Anoplura: Pediculidae) from Buenos Aires.

    PubMed

    Picollo, M I; Vassena, C V; Mougabure Cueto, G A; Vernetti, M; Zerba, E N

    2000-09-01

    Permethrin-resistant colonies of Pediculus capitis (De Geer) from Buenos Aires were used to establish a resistance profile and to examine resistance mechanisms. All permethrin-resistant head lice (resistance ratio from 52.8 to > 88.7) were also resistant to d-phenothrin (resistance ratio from 40.86 to > 48.39) and deltamethrin (resistance ratio from 16.24 to 38.06). No cross-resistance to carbaryl was found in any of the pyrethroid-resistant P. capitis tested. Otherwise, all resistant colonies showed low to high levels of resistance to beta-cypermethrin. This pyrethroid had never been applied as a pediculicide in Argentina; however, the high level of resistance found in these permethrin-resistant colonies (resistance ratio from 9.74 to 50.97) demonstrated that pyrethroid cross-resistance occurred to this novel insecticide. Treatment with piperonyl butoxide (PBO) or triphenylphosphate (TPP) significantly decreased the toxicity of permethrin in the four colonies tested. The esterase inhibitor TPP produced lower enhancement of toxicity than the multifunction oxidase inhibitor PBO in the colonies having the highest resistance levels. Results presented here concerning the cross-resistance profile and synergism by enzyme inhibitors in permethrin-resistant head lice demonstrated that enhanced metabolism was involved in the pyrethroid resistance. However, the substantial degree of resistance that remained after synergism suggested the presence of another resistance mechanism. Cross-resistance to pyrethroid and susceptibility to the carbamate carbaryl suggested a common action mechanism. PMID:11004784

  11. Prevalence and risk factors of Pediculus (humanus) capitis (Anoplura: Pediculidae), in primary schools in Sanandaj City, Kurdistan Province, Iran.

    PubMed

    Vahabi, A; Shemshad, K; Sayyadi, M; Biglarian, A; Vahabi, B; Sayyad, S; Shemshad, M; Rafinejad, J

    2012-06-01

    Human head lice, Pediculus (humanus) capitis, infest people worldwide and are most prevalent in children. The aim of this study was to determine the prevalence of head lice, in relation to socioeconomic status of the family and hygienic practices in the home. The prevalence rate was determined in 27 primary schools that had 810 students in Sanandaj city who were selected by multistage, systematic random sampling. A total of 38 students from all grades were infested with different rates of infestations. In addition, standard questionnaire recorded information about demographic features of each student were fulfilled. Children aged 10-11 years were the most frequently affected, there was a significant relationship between head louse infestation, family income and parents education level (α=5%). Pediculosis is a public health problem in many parts of the world. Pediculosis was found to be more prevalent among children of fathers with lower level of education and socioeconomic status, it is necessary to give health education to families in order to prevent pediculosis in this area. PMID:22735841

  12. The prevalence of Pediculus humanus capitis and the coexistence of intestinal parasites in young children in boarding schools in Sivas, Turkey.

    PubMed

    Değerli, Serpil; Malatyali, Erdoğan; Çeliksöz, Ali; Özçelik, Semra; Mumcuoğlu, Kosta Y

    2012-01-01

    The aim of this study was to investigate the prevalence of Pediculus humanus capitis and the coexistence of intestinal parasites in boarding primary schools in Sivas, Turkey. Seven hundred seventy-two students (350 [45.3%] girls, 422 [54.7%] boys) were evaluated with combing for the presence of head lice, collection of fecal samples, and examination of the perianal region for intestinal parasites using the cellophane tape method. The overall infestation rate for head lice was 6% (n=46). Nine children had evidence of nits only (1.2%), whereas living lice and nits or eggs were found in 37 children (4.8%). Girls were significantly more commonly infested (12.9%) than boys (0.2%). Of the parameters evaluated, socioeconomic level, number of rooms per family, and size and weight of the children were statistically significantly different between the children with and without lice. Although the infestation rate of children with intestinal parasites was higher in the head louse-infested group (23.9%) than in the group of children without lice (17.6%), the differences were not statistically significant. PMID:22107034

  13. Lethal effects of treatment with a special dimeticone formula on head lice and house crickets (Orthoptera, Ensifera: Acheta domestica and Anoplura, phthiraptera: Pediculus humanus). Insights into physical mechanisms.

    PubMed

    Richling, Ira; Böckeler, Wolfgang

    2008-01-01

    The present study provides the first convincing explanation of the mode of action of the medical device NYDA, a special dimeticone (CAS 9006-65-9) formula containing 92% of two dimeticones with different viscosities specifically designed for the physical treatment of head lice infestations (pediculosis capitis) by suffocation. Both, lice (Pediculus humanus) and house crickets (Acheta domestica) treated with this anti-head lice product are knocked out to the status "of no major vital signs" within less than 1 min that in consequence is accompanied irreversibly with the death of the respective insects. Scanning electron microscopical investigations have revealed that the cuticle is coated by a thin closed layer of the dimeticone formula that also enters the stigmata. In vivo observations and dissections of Acheta domestica have shown that application of the medical device to the thoracic stigmata invariably leads to rapid death; this is strongly correlated with the influx of the special dimeticone formula into the head trachea, whereby the solution effectively blocks the oxygen supply of the central nervous system. Dissections after application of the stained product show that it also enters the finest tracheal branches. Analogous in vivo observations in Pediculus humanus have confirmed the correlation between the disappearance of major vital signs and the displacement of air by the dimeticone formula in the tracheal system of the head. For both insect species, statistical data are provided for the chronological sequence of the filling of the tracheal system in relation to the respective vitality conditions of the Insects. On average, the special dimeticone formula reaches the insect's head tracheae within 0.5 min in house crickets and in less than 1 min in lice with a complete filling of the entire head tracheal system of lice within 3.5 min. In addition, a timed sequence of images illustrates this process for lice. The experiments clearly reveal the exclusive and

  14. In vitro efficacy of over-the-counter botanical pediculicides against the head louse Pediculus humanus var capitis based on a stringent standard for mortality assessment.

    PubMed

    Heukelbach, J; Canyon, D V; Oliveira, F A; Muller, R; Speare, R

    2008-09-01

    Infestation of the head louse Pediculus humanus var capitis DeGeer (Phthiraptera: Pediculidae) is an important public health problem in Australia, with up to a third of children infested in some primary schools. Insecticide resistance and inadequate attention to the application instructions of topical pediculicides are common reasons for treatment failure. This study evaluated six popular Australian over-the-counter products against head lice, primarily comprised of different botanical extracts, and compared them with permethrin 1% (Quellada) and a non-treatment control in order to assess their in vitro efficacy. We also assessed commonly used criteria for evaluating pediculicide efficacy in vitro. All tested products failed to demonstrate high levels of efficacy with the exception of Tea Tree Gel((R)), which outperformed 1% permethrin. Permethrin had a high level of efficacy, but using stringent criteria 18% of lice were not dead at 3 h, indicating some resistance to Quellada. Commonly used less stringent criteria were shown to overestimate mortality of head lice as a result of the protective phenomenon of stasis or sham death observed in exposed lice that may recover after some time. Using two different levels of stringency resulted in different rankings of efficacy for most products, with the exception of the first ranked product, Tea Tree Gel. Rankings of efficacy also varied over time, even within the different assessment criteria. Government regulatory agencies should require standard in vitro tests using stringent mortality criteria, with an observation period of >or= 6 h, to determine the efficacy of new pediculicides, and only products that cause a minimum mortality rate (e.g. 80%) in head lice collected from the target population should be licensed for sale. PMID:18816275

  15. Identification and characterization of an esterase involved in malathion resistance in the head louse Pediculus humanus capitis.

    PubMed

    Kwon, Deok Ho; Kim, Ju Hyeon; Kim, Young Ho; Yoon, Kyong Sup; Clark, J Marshall; Lee, Si Hyeock

    2014-06-01

    Enhanced malathion carboxylesterase (MCE) activity was previously reported to be involved in malathion resistance in the head louse Pediculus humanus capitis (Gao et al., 2006 [8]). To identify MCE, the transcriptional profiles of all five esterases that had been annotated to be catalytically active were determined and compared between the malathion-resistant (BR-HL) and malathion-susceptible (KR-HL) strains of head lice. An esterase gene, designated HLCbE3, exhibited approximately 5.4-fold higher transcription levels, whereas remaining four esterases did not exhibit a significant increase in their transcription in BR-HL, indicating that HLCbE3 may be the putative MCE. Comparison of the entire cDNA sequences of HLCbE3 revealed no sequence differences between the BR-HL and KR-HL strains and suggested that no single nucleotide polymorphism is associated with enhanced MCE activity. Two copies of the HLCbE3 gene were observed in BR-HL, implying that the over-transcription of HLCbE3 is due to the combination of a gene duplication and up-regulated transcription. Knockdown of HLCbE3 expression by RNA interference in the BR-HL strain led to increases in malathion susceptibility, confirming the identity of HLCbE3 as a MCE responsible for malathion resistance in the head louse. Phylogenetic analysis suggested that HLCbE3 is a typical dietary esterase and belongs to a clade containing various MCEs involved in malathion resistance. PMID:24974112

  16. Study of archaeological nits/eggs of Pediculus humanus capitis by scanning electron microscopy.

    PubMed

    Arriaza, Bernardo; Standen, Vivien; Núñez, Hipólito; Reinhard, Karl

    2013-02-01

    This paper presents and discusses archaeological samples of Pediculus humanus capitis nits/eggs in Arica, northern Chile, dating between 2000 B.C. and A.D. 500. Eight samples of nits/eggs taken directly from seven mummified bodies of both the valley and the coast of Arica, were collected and studied. Samples were analysed with scanning electron microscopy (SEM), uncoated, using low and variable pressure modes. The aim was to study the morphology of the nits/eggs, the different degrees of preservation and their research potential. All samples were in good external condition and due to manipulation before SEM analysis, the oldest ones were fractured allowing the observation in situ of the hatching ad portas of an embryo. This inside view of the egg allowed observation and identification of microstructures of the embryo such as abdominal and thoracic spiracles and claws. In the most recent and best preserved samples, external structures characteristic of the egg such as aeropyles and operculum were observed. SEM can contribute significantly to the study of ectoparasites that affected ancient American populations and in this particular case to illustrate the stages and morphology of Andean archaeological specimens of P. humanus capitis. PMID:23176818

  17. Contact and fumigant toxicity of hexane flower bud extract of Syzygium aromaticum and its compounds against Pediculus humanus capitis (Phthiraptera: Pediculidae).

    PubMed

    Bagavan, Asokan; Rahuman, Abdul Abdul; Kamaraj, Chinnaperumal; Elango, Gandhi; Zahir, Abdul Abduz; Jayaseelan, Chidambaram; Santhoshkumar, Thirunavukkarasu; Marimuthu, Sampath

    2011-11-01

    The head lice, Pediculus humanus capitis De Geer is an obligate ectoparasite of humans that causes pediculosis capitis, a nuisance for millions of people worldwide, with high prevalence in children. P. humanus capitis has been treated by methods that include the physical remotion of lice, various domestic treatments, and conventional insecticides. None of these methods render complete protection, and there is clear evidence for the evolution of resistance and cross-resistance to conventional insecticides. Non-toxic alternative options are hence needed for head lice treatment and/or prevention, and natural products from plants are good candidates for safer control agents that may provide good anti-lice activity. The plant extracts are good and safe alternatives due to their low toxicity to mammals and easy biodegradability. The present study carried out the pediculocidal activity using the hexane flower bud extract of Syzygium aromaticum (Myrtaceae) against P. humanus capitis examined by direct contact and fumigant toxicity (closed- and open-container methods) bioassay. The chemical composition of S. aromaticum flower bud hexane extract was analyzed by gas chromatography-mass spectrometry. The major chemical constituent (58.79%) of flower bud hexane extract S. aromaticum was identified as chavibetol (5-allyl-2-methoxyphenol) by comparison of mass spectral data and retention times. The hexane extract of S. aromaticum was subjected to gas chromatography analysis, and totally 47 compounds were detected, of which chavibetol was predominantly present. The other major constituents present in the hexane extract were eugenol acetate (phenol,2-methoxy-4-(2-propenyl)-,acetate (15.09%), caryophyllene-(I1) (2,6,10,10-tetramethyl bicyclo [7.2.0] undeca-1,6-diene (13.75%), caryophyllene oxide (3.04%), 2,6,6,9-tetramethyl-1,4,8-cycloundecatriene (1.67%), and copaene (1.33%). The filter paper contact bioassay study showed pronounced pediculicidal activity in the flower bud hexane

  18. Ovicidal and adulticidal activity of Eucalyptus globulus leaf oil terpenoids against Pediculus humanus capitis (Anoplura: Pediculidae).

    PubMed

    Yang, Young-Cheol; Choi, Han-Young; Choi, Won-Sil; Clark, J M; Ahn, Young-Joon

    2004-05-01

    The toxic effects of Eucalyptus globulus leaf oil-derived monoterpenoids [1,8-cineole, l-phellandrene, (-)-alpha-pinene, 2-beta-pinene, trans-pinocarveol, gamma-terpinene, and 1-alpha-terpineol] and the known Eucalyptusleaf oil terpenoids (beta-eudesmol and geranyl acetate) on eggs and females of the human head louse, Pediculus humanus capitis, were examined using direct contact and fumigation bioassays and compared with the lethal activity of delta-phenothrin and pyrethrum, two commonly used pediculicides. In a filter paper contact bioassay with female P. h. capitis, the pediculicidal activity was more pronounced with Eucalyptus leaf oil than with either delta-phenothrin or pyrethrum on the basis of LT(50) values (0.125 vs 0.25 mg/cm(2)). 1,8-Cineole was 2.2- and 2.3-fold more toxic than either delta-phenothrin or pyrethrum, respectively. The pediculicidal activities of (-)-alpha-pinene, 2-beta-pinene, and (E)-pinocarveol were comparable to those of delta-phenothrin and pyrethrum. l-Phellandrene, gamma-terpinene, and 1-alpha-terpineol were relatively less active than delta-phenothrin and pyrethrum. beta-Eudesmol and geranyl acetate were ineffective. 1-alpha-Terpineol and (E)-pinocaveol were highly effective at 0.5 and 1.0 mg/cm(2), respectively, against P. h. capitis eggs. At 1.0 mg/cm(2), (-)-alpha-pinene, 2-beta-pinene, and gamma-terpinene exhibited moderate ovicidal activity, whereas little or no ovicidal activity was observed with the other terpenoids and with delta-phenothrin and pyrethrum. In fumigation tests with female P. h. capitis at 0.25 mg/cm(2), 1,8-cineole, (-)-alpha-pinene, (E)-pinocarveol, and 1-alpha-terpineol were more effective in closed cups than in open ones, indicating that the effect of the monoterpenoids was largely due to action in the vapor phase. Neither delta-phenothrin nor pyrethrum exhibited fumigant toxicity. Eucalyptus leaf oil, particularly 1,8-cineole, 1-alpha-terpineol, and (E)-pinocaveol, merits further study as potential

  19. Chemical composition and efficacy of some selected plant oils against Pediculus humanus capitis in vitro.

    PubMed

    Yones, Doaa A; Bakir, Hanaa Y; Bayoumi, Soad A L

    2016-08-01

    Natural compounds have been suggested as alternative sources for pediculosis capitis control. We aimed to investigate the chemical composition and evaluate the pediculicidal activity of spearmint, clove, cassia, thyme, eucalyptus, and anise essential oils in addition to sesame oil against human head lice in vitro. A filter paper contact bioassay method was used by applying 0.25 and 0.5 mg/cm(2) of each tested oil to filter paper in Petri dishes with 15 females head lice and another with ten nits. The lice mortalities were reported every 5 min for 180 min. The percentage of inhibition of hatch (PIH) was used to calculate ovicidal activity by daily microscopic inspections 5 days after the hatching of controls. Comparison with the widely used pediculicide (malathion) was performed. The most effective essential oil was spearmint followed by cassia and clove with KT50 values of 4.06, 7.62, and 12.12 at 0.5 mg/cm(2) and 8.84, 11.38, and 19.73 at 0.25 mg/cm(2), respectively. Thyme, eucalyptus, and anise were also effective adulticides with KT50 values of 18.61, 32.65, and 37.34 at 0.5 mg/cm(2) and 29.92, 43.16, and 45.37 at 0.25 mg/cm(2), respectively. Essential oils were also successful in inhibiting nymph emergence. Spearmint oil was the most effective, with a complete inhibition of emergence at 0.5 mg/cm(2). Sesame fixed oil did not show any adulticidal or ovicidal activity against head lice in vitro. The observed insecticidal activity was comparable to malathion. The results herein described the effectiveness of these essential oils as potential pediculicides for head lice control. Incorporation of essential oils in pediculicide formulations needs proper formulation and clinical trials. PMID:27112758

  20. Fumigant and repellent properties of essential oils and component compounds against permethrin-resistant Pediculus humanus capitis (Anoplura: Pediculidae) from Argentina.

    PubMed

    Toloza, Ariel Ceferino; Zygadlo, Julio; Cueto, Gastón Mougabure; Biurrun, Fernando; Zerba, Eduardo; Picollo, María Inés

    2006-09-01

    The repeated use of permethrin and other insecticides for the control of head lice, Pediculus humanus capitis De Geer (Anoplura: Pediculidae), during past decades has resulted in the development of marked levels of resistance. Thus, new alternative insecticides are needed for the control of head lice. We studied the fumigant and repellent properties of essential oils from 16 native and exotic plants in Argentina, and 21 chemical components against permethrin-resistant head lice from Argentina. With a direct vapor-exposure bioassay, the most effective oil was from the native Myrcianthes cisplatensis Cambess (Myrtaceae) with a time to 50% knockdown (KT50) of 1.3 min, followed by exotic species, Eucalyptus cinerea F.V. Muell., Eucalyptus viminalis Labill., and Eucalyptus saligna Smith. with KT50 values of 12.0, 14.9, and 17.4 min, respectively. The most effective components were 1,8-cineole and anisole, with KT50 values of 11.1 and 12.7 min, respectively. Regression analysis of KT50 values and vapor pressures and water-partition coefficients for the essential oil components revealed that the most effective fumigants were among the more volatile components. Repellency assays indicated that the essential oil from Mentha pulegium L. and its benzyl alcohol component were the most effective repellents, having repellency indices of 75.5 and 57.8%, respectively. Thus, some Argentinean plants contain essential oils and components that function as fumigants or as repellents and thereby show potential for development of new control products for head lice. PMID:17017225

  1. Effectiveness of lotions based on essential oils from aromatic plants against permethrin resistant Pediculus humanus capitis.

    PubMed

    Gonzalez Audino, Paola; Vassena, Claudia; Zerba, Eduardo; Picollo, María

    2007-10-01

    In Argentina, field populations of the head louse Pediculus humanus capitis De Geer (Phthiraptera: Pediculidae) have developed resistance to permethrin and other pyrethroids. Thus, the aim of this work was the development of a lotion containing essential oils from plants and an alcoholic coadjuvant to improve biological effect. Ethanol + isopropanol (1 + 1 in volume) 50% in water and ethanol 96% were taken as bases for preparation of experimental lotions containing essential oils from plants. We found that experimental lotions containing lavender, peppermint and eucalyptus oils in a 5% composition and the combination of eucalyptus and peppermint in a total concentration of 10%, dissolved in 50% ethanol + isopropanol (1 + 1) in water, showed the best knockdown effect. On the other side, lotion containing peppermint oil and eucalyptus oil (1 + 1) 10%, dissolved in ethanol 96%, showed to be as effective as the best commercial lotion now available in Argentina. Furthermore, addition of 1-dodecanol in all cases increased the effectiveness of all the experimental lotions. This difference is significantly important for 1-dodecanol concentration of 10%, reaching a toxic activity compared to the best commercial lotion available in the market. PMID:17647002

  2. A ghost covered in lice: a case of severe blood loss with long-standing heavy pediculosis capitis infestation.

    PubMed

    Hau, Veronica; Muhi-Iddin, Nadia

    2014-01-01

    An 11-year-old child presented with poor school attendance, and signs and symptoms of severe anaemia. He was heavily covered in lice. He was investigated for other causes of anaemia. Following treatment for head lice and also iron supplementation, he was back in full-time education. This case highlights the link between head lice (pediculosis capitis) infestation and iron-deficiency anaemia. PMID:25527684

  3. Lice.

    PubMed

    Do-Pham, Giao; Monsel, Gentiane; Chosidow, Olivier

    2014-09-01

    Pediculosis (capitis, corporis, and pubis) share well-known features: worldwide prevalence (involving millions of people annually); parasites inducing skin lesions directly, and indirectly as a result of itching and hypersensitivity to parasites; and treatment based on good entomological knowledge of the parasite and practical considerations (ie, most available treatments do not act on eggs and should be repeated, depending on the life cycle of the parasites). Infestations are spread most commonly by close contacts. Social stigma and persistent misconceptions complicate the implementation of appropriate management strategies. Head and pubic lice infestations are diagnosed by the visualization of insects or viable nits (eggs). Primary treatments are topical pediculicides (permethrin or malathion), used twice, but emergence of resistance against pediculicides has created the need of alternative treatments including topical or oral ivermectin. Pubic lice are treated the same as head lice, but this finding should prompt evaluation for other sexually transmitted diseases. Body lice infestation should be suspected when symptoms of generalized itching occur in persons who do not change or wash their clothing or bedding regularly; lice may be found in the seams of their clothing.Topically administered permethrin may help to eradicate body lice, but personal hygiene measures are essential for successful treatment. Environmental treatment is also necessary for the eradication of the infestation. Health care personnel who come into contact with this population need to be well informed of the facts in order to disseminate accurate information for diagnosis and management. PMID:25577849

  4. PREHISTORICAL Pediculus humanus capitis INFESTATION: QUANTITATIVE DATA AND LOW VACUUM SCANNING MICROSCOPY

    PubMed Central

    Dutra, Juliana M.F.; Alves, Arthur Daniel; Pessanha, Thaila; Rachid, Rachel; de Souza, Wanderley; Linardi, Pedro Marcos; Ferreira, Luiz Fernando; de Souza, Sheila Mendonça; Araujo, Adauto

    2014-01-01

    A pre-Columbian Peruvian scalp was examined decades ago by a researcher from the Oswaldo Cruz Foundation. Professor Olympio da Fonseca Filho described nits and adult lice attached to hair shafts and commented about the origin of head lice infestations on mankind. This same scalp was sent to our laboratory and is the subject of the present paper. Analysis showed a massive infestation with nine eggs/cm2 and an impressive number of very well preserved adult lice. The infestation age was roughly estimated as nine months before death based on the distance of nits from the hair root and the medium rate of hair growth. A small traditional textile was associated with the scalp, possibly part of the funerary belongings. Other morphological aspects visualized by low-vacuum scanning electron microscopy are also presented here for adults and nits. PMID:24626412

  5. Prehistorical Pediculus humanus capitis infestation: quantitative data and low vacuum scanning microscopy.

    PubMed

    Dutra, Juliana M F; Alves, Arthur Daniel; Pessanha, Thaila; Rachid, Rachel; Souza, Wanderley de; Linardi, Pedro Marcos; Ferreira, Luiz Fernando; Souza, Sheila Mendonça de; Araujo, Adauto

    2014-01-01

    A pre-Columbian Peruvian scalp was examined decades ago by a researcher from the Oswaldo Cruz Foundation. Professor Olympio da Fonseca Filho described nits and adult lice attached to hair shafts and commented about the origin of head lice infestations on mankind. This same scalp was sent to our laboratory and is the subject of the present paper. Analysis showed a massive infestation with nine eggs/cm2 and an impressive number of very well preserved adult lice. The infestation age was roughly estimated as nine months before death based on the distance of nits from the hair root and the medium rate of hair growth. A small traditional textile was associated with the scalp, possibly part of the funerary belongings. Other morphological aspects visualized by low-vacuum scanning electron microscopy are also presented here for adults and nits. PMID:24626412

  6. Pediculicidal effect of herbal shampoo against Pediculus humanus capitis in vitro.

    PubMed

    Watcharawit, R; Soonwera, M

    2013-06-01

    Human head lice infestation is an important public health problem in Thailand. Lice resistance is increasing, chemical pediculicides have lost their efficacy and thus alternative products such as herbal shampoos have been proposed to treat lice infestation. The present study investigated the efficacy of twenty nine herbal shampoos based on zinbiberaceae plants, piperaceae plants and native plants against human head lice and compared them with malathion shampoo (A-lices shampoo®: 1% w/v malathion) and commercial shampoo (BabiMild Natural'N Mild®) in order to assess their in vitro efficacy. All herbal shampoo were more effective than commercial shampoo with 100% mortality at 60 seconds and LT50 values ranged from 11.30 to 31.97 seconds, meanwhile, commercial shampoo caused 14.0-15.0% mortality and LT50 values ranged from 83.96 to 87.43 seconds. The nine herbal shampoos from Zingiber cassumunar, Piper betle, Piper ribesioides, Averrhoa bilimbi, Clitoria ternatea, Plectranthus amboincus, Myristica fragrans, Tacca chantrieri and Zanthoxylum limonella were more effective pediculicide than malathion shampoo with 100% mortality at 30 seconds and LT50 values ranged from 11.30-13.58 seconds, on the other hand malathion shampoo showed LT50 values ranging from 12.39 to 13.67 seconds. LT50 values indicated the order of pediculicidal activity in the herbal shampoos as Z. cassumunar shampoo > P. betle shampoo > Za. limonella shampoo > Av. bilimbi shampoo > P. ribesioides shampoo > My. fragrans shampoo > T. chantrieri shampoo > Pl. amboincus shampoo. Our data showed that eight of the twenty nine herbal shampoos in this study were of high potential pediculicide to human head lice treatments for Thai children. PMID:23959497

  7. Insecticidal activity of individual and mixed monoterpenoids of geranium essential oil against Pediculus humanus capitis (Phthiraptera: Pediculidae).

    PubMed

    Gallardo, A; Picollo, M I; González-Audino, P; Mougabure-Cueto, G

    2012-03-01

    The major components of geranium (Geranium maculatum L.) oil and their mixtures were tested against female Pediculus humanus capitis De Geer (Phthiraptera: Pediculidae). Chemical analysis by gas chromatography coupled to mass spectrometry revealed four major constituents: citronellol (38%), geraniol (16%), citronellyl formate (10.4%), and linalool (6.45%) (concentration expressed as percentage of total). Topical application demonstrated that the most potent component was citronellol and geraniol, with LD50 values 9.7 and 12.7 microg/insect, respectively. Linalool and Citronellyl formate were less toxic with LD50 values 24.7 and 38.5 microg/insect, respectively. Toxicity of these four major constituents in the same proportion as the natural oil, was greater than whole oil and each individual component. Removal of any four constituents produced a decreased in effectiveness. The absence of citronellol caused the greatest decrease in toxicity (DL50 from 2.2 to 10.9 microg/insect), leading us to conclude that this constituent is the major contributor to oil toxicity. The knowledge of the role of each constituent in the toxicity of the whole oil gives the possibility to create artificial blends of different constituents for the development of more effective control agents. PMID:22493851

  8. Influence of the formulations in removing eggs of Pediculus humanus capitis (Phthiraptera: Pediculidae).

    PubMed

    Ortega-Insaurralde, Isabel; Toloza, Ariel Ceferino; Picollo, María Inés; Vassena, Claudia

    2014-09-01

    Head lice lay eggs in human head hairs in order to reproduce. There is a difficulty associated to the process of detaching these eggs: they are tightly gripped to the hair by a secretion produced by female head lice. The physical removal of eggs has become an important part of treatment of louse infestations. The finding of new products to loosen the eggs is necessary to avoid mistaken diagnosis or reinfestations. This work aimed to compare different kinds of pediculicide formulations in order to find if their presentations represented differences in the egg remover effect. We also wanted to present a new device to test the efficacy of the egg remover formulations. Products with creamy presentations (Bio infant lice and egg remover and hair conditioner) and one containing dimethicone (Nyda) showed the lower mean forces compared with the control (lower mean forces represented best removal activity). Whereas, the Biferdil egg remover (gel) and Nopucid Tribit (hydroalcoholic lotion) had no egg removal effect, presenting the highest mean forces (177.82 and 189.99 mN, respectively) compared with the control. Additionally, we proposed a removal index (RI) to compare the efficacy of different products on the egg removal activity (RI > 0, good performance). The higher index values were for Bio infant lice and egg remover (0.72) and Biferdil hair conditioner (0.58). The lowest index values were for Biferdil egg remover (-0.26) and Nopucid Tribit (-0.35).The formulation of over the counter pediculicides in the egg remover effect was discussed. PMID:25033812

  9. Lousicidal activity of synthesized silver nanoparticles using Lawsonia inermis leaf aqueous extract against Pediculus humanus capitis and Bovicola ovis.

    PubMed

    Marimuthu, Sampath; Rahuman, Abdul Abdul; Santhoshkumar, Thirunavukkarasu; Jayaseelan, Chidambaram; Kirthi, Arivarasan Vishnu; Bagavan, Asokan; Kamaraj, Chinnaperumal; Elango, Gandhi; Zahir, Abdul Abduz; Rajakumar, Govindasamy; Velayutham, Kanayairam

    2012-11-01

    In the present work, we describe inexpensive, nontoxic, unreported and simple procedure for synthesis of silver nanoparticles (Ag NPs) using leaf aqueous extract of Lawsonia inermis as eco-friendly reducing and capping agent. The aim of the present study was to assess the lousicidal activity of synthesized Ag NPs against human head louse, Pediculus humanus capitis De Geer (Phthiraptera: Pediculidae), and sheep body louse, Bovicola ovis Schrank (Phthiraptera: Trichodectidae). Direct contact method was conducted to determine the potential of pediculocidal activity and impregnated method was used with slight modifications to improve practicality and efficiency of tested materials of synthesized Ag NPs against B. ovis. The synthesized Ag NPs characterized with the UV showing peak at 426 nm. X-ray diffraction (XRD) spectra clearly shows that the diffraction peaks in the pattern indexed as the silver with lattice constants. XRD analysis showed intense peaks at 2θ values of 38.34°, 44.59°, 65.04°, and 77.77° corresponding to (111), (200), (220), and (311) Bragg's reflection based on the fcc structure of Ag NPs. Fourier transform infrared spectroscopy (FTIR) spectra of Ag NPs exhibited prominent peaks at 3,422.13, 2,924.12, 2,851.76, 1,631.41, 1,381.60, 1,087.11, and 789.55 cm(-1). Scanning electron microscopy (SEM) micrograph showed mean size of 59.52 nm and aggregates of spherical shape Ag NPs. Energy dispersive X-ray spectroscopy (EDX) showed the complete chemical composition of the synthesized Ag NPs. In pediculocidal activity, the results showed that the optimal times for measuring percent mortality effects of synthesized Ag NPs were 26, 61, 84, and 100 at 5, 10, 15, and 20 min, respectively. The average percent mortality for synthesized Ag NPs was 33, 84, 91, and 100 at 10, 15, 20, and 35 min, respectively against B. ovis. The maximum activity was observed in the aqueous leaf extract of L. inermis, 1 mM AgNO(3) solution, and synthesized Ag NPs against P. humanus

  10. Prevalence of Pediculus humanus capitis among school girls of Chuang-Wei and Nan-Ao Districts in I-Lan County and Man-Chow District in Ping-Tung County, Taiwan.

    PubMed

    Chao, D; Liu, H Y; Fan, P C

    1981-03-01

    By using the naked eye examination and comb method, a field survey and combing collection of head louse (Pediculus humanus capitis) among school girls in three different area (Man-Chow, Nan-Ao and Chuang-Wei) of Taiwan were performed from July 1979 to February, 1980. The general infestation rate of head louse was 39.8% (or 998/2,509). In the primary schools, comparatively, the rate at Man-Chow (66.7%) was highest, the next at Nan-Ao (55.4%) and the lowest at Chuang-Wei (39.4%). While in the junior high schools, the rate was apparently higher at Nan-Ao (38.4%) than that at Man-Chow (15.6%) and Chang-Wei (12.0%). The highest rate in the primary schools was found in 3rd graders except at Chuang-Wei in 5th graders. The corresponding figure in the junior high schools was found in 1st graders except at Nan-Ao in 2nd graders. Of 774 infested girls studied, according to the number of lice per infested girl, the percentages of infestation in the 5 groups were: the very light (nits only) 54.5, light (1-10) 38.5, moderate (11-50) 6.5, heavy (51-100) 0.4 and very heavy (over 100) 0.1 respectively. Of 2,178 head lice examined, 53.0% was nymphs; 28.7% females; 18.2% males. The average number of head louse in each infested girl 6.2. PMID:7261698

  11. Efficacy of products to remove eggs of Pediculus humanus capitis (Phthiraptera: Pediculidae) from the human hair.

    PubMed

    Lapeere, Hilde; Brochez, Lieve; Verhaeghe, Evelien; Stichele, Robert H Vander; Remon, Jean-Paul; Lambert, Jo; Leybaert, Luc

    2014-03-01

    Head lice infestations are very common in children aged between 3 and 12 yr old. The eggs of the head louse are difficult to remove and remain firmly attached to the hair even after any head louse treatment. Solid in vitro and in vivo evidence to support the use of any of the proposed products to facilitate nit removal is scarce. The objective of the current study was to determine the efficacy of several products to remove eggshells from human hair using an objective measurement procedure. Water and ordinary hair conditioner significantly facilitated the removal of nits in vitro. We found no difference between ordinary conditioner and products specifically marketed for the purpose of nit removal. Other products such as formic acid solution and almond oil did not have a beneficial effect. PMID:24724290

  12. Lice

    MedlinePlus

    ... Intense itching Rash Visible nits (lice eggs) or crawling lice Lice spread most commonly by close person- ... do not spread human lice. Lice move by crawling. They cannot hop or fly. If you get ...

  13. [Pyrethroid resistance mechanisms in the body lice Pediculus humanus humanus L.: detoxification enzyme systems].

    PubMed

    Lopatina, Iu V; Eremina, O Iu; Iakovlev, É A

    2014-01-01

    Synergists (piperonyl butoxide, MGK-264 (N-octyl bicycloheptene dicarboximide), DEF (S, S, S, tributyl phosphorotrithioate), and diethylmaleate) were used to investigate the metabolic resistance of body lice to permethrin. Instances of the synergistic activity ofpermethrin when combined with enzyme system inhibitors have been identified. The synergic ratios were 3.3 to 52.0 for monooxygenase inhibitors; 5.2 to 7.4 for esterases, and about 4 for glutathione-S-transferases. Since the use of the synergists did not lead to full inhibition of resistance, it was concluded that the lice had also a kdr-like type of resistance. PMID:24738222

  14. Cytogenetic Features of Human Head and Body Lice (Phthiraptera: Pediculidae).

    PubMed

    Bressa, María José; Papeschi, Alba Graciela; Toloza, Ariel Ceferino

    2015-09-01

    The genus Pediculus L. that parasitize humans comprise two subspecies: the head lice Pediculus humanus capitis De Geer and the body lice Pediculus humanus humanus De Geer. Despite the 200 yr of the first description of these two species, there is still a long debate about their taxonomic status. Some authors proposed that these organisms are separate species, conspecifics, or grouped in clades. The sequencing of both forms indicated that the difference between them is one gene absent in the head louse. However, their chromosomal number remains to be determined. In this study, we described the male and female karyotypes, and male meiosis of head and body lice, and examined the chromatin structure by means of C-banding. In P. h. humanus and P. h. capitis, the diploid chromosome complement was 2 n = 12 in both sexes. In oogonial prometaphase and metaphase and spermatogonial metaphase, it is evident that chromosomes lack of a primary constriction. No identifiable sex chromosomes or B chromosomes were observed in head and body lice. Neither chiasmata nor chromatin connections between homologous chromosomes were detected in male meiosis. The meiotic behaviour of the chromosomes showed that they are holokinetic. C-banding revealed the absence of constitutive heterochromatin. Our results provide relevant information to be used in mapping studies of genes associated with sex determination and environmental sensing and response. PMID:26336229

  15. Pediculosis capitis: new insights into epidemiology, diagnosis and treatment.

    PubMed

    Feldmeier, H

    2012-09-01

    Pediculosis capitis is a ubiquitous parasitic skin disease caused by Pediculus humanus capitis. Head lice are highly specialised parasites which can propagate only on human scalp and hair. Transmission occurs by direct head-to-head contact. Head lice are vectors of important bacterial pathogens. Pediculosis capitis usually occurs in small epidemics in play groups, kindergartens and schools. Population-based studies in European countries show highly diverging prevalences, ranging from 1% to 20%. The diagnosis of head lice infestation is made through the visual inspection of hair and scalp or dry/wet combing. The optimal method for the diagnosis of active head lice infestation is dry/wet combing. Topical application of a pediculicide is the most common treatment. Compounds with a neurotoxic mode of action are widely used but are becoming less effective due to resistant parasite populations. Besides, their use is restricted by safety concerns. Dimeticones, silicone oils with a low surface tension and the propensity to perfectly coat surfaces, have a purely physical mode of action. This group of compounds is highly effective and safe, and there is no risk that head lice become resistant. The control of epidemics requires active contact tracing and synchronised treatment with an effective and safe pediculicide. PMID:22382818

  16. Solanum trilobatum extract-mediated synthesis of titanium dioxide nanoparticles to control Pediculus humanus capitis, Hyalomma anatolicum anatolicum and Anopheles subpictus.

    PubMed

    Rajakumar, Govindasamy; Rahuman, Abdul Abdul; Jayaseelan, Chidambaram; Santhoshkumar, Thirunavukkarasu; Marimuthu, Sampath; Kamaraj, Chinnaperumal; Bagavan, Asokan; Zahir, Abdul Abduz; Kirthi, Arivarasan Vishnu; Elango, Gandhi; Arora, Pooja; Karthikeyan, Rajan; Manikandan, Sivan; Jose, Sujin

    2014-02-01

    Titanium dioxide nanoparticles (TiO2 NPs) are widely used in paints, printing ink, rubber, paper, cosmetics, sunscreens, car materials, cleaning air products, industrial photocatalytic processes, and decomposing organic matters in wastewater due to their unique physical, chemical, and biological properties. The present study was conducted to assess the antiparasitic efficacies of synthesized TiO2 NPs utilizing leaf aqueous extract of Solanum trilobatum against the adult head louse, Pediculus humanus capitis De Geer (Phthiraptera: Pediculidae); larvae of cattle tick Hyalomma anatolicum (a.) anatolicum Koch (Acari: Ixodidae), and fourth instar larvae of malaria vector Anopheles subpictus Grassi (Diptera: Culicidae). The green synthesized TiO2 NPs were analyzed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy analysis (EDX), and Atomic force microscopy (AFM). XRD analysis of synthesized TiO2 NPs revealed that the particles were in the form of nanocrystals as evidenced by the major peaks at 2θ values of 27.52°, 36.21°, and 54.43° identified as 110, 101, and 211 reflections, respectively. FTIR spectra exhibited a prominent peak at 3,466 cm(-1) and showed OH stretching due to the alcoholic group, and the OH group may act as a capping agent. SEM images displayed NPs that were spherical, oval in shape, individual, and some in aggregates with an average size of 70 nm. Characterization of the synthesized TiO2 NPs using AFM offered a three-dimensional visualization and uneven surface morphology. The pediculocidal and acaricidal activities of synthesized TiO2 NPs showed the percent mortality of 31, 42, 63, 82, 100; 36, 44, 67, 89, and 100 at 2, 4, 6, 8, and 10 mg/L, respectively, against P. h. capitis and H. a. anatolicum. The average larval percent mortality of synthesized TiO2 NPs was 38, 47, 66, 79, and 100 at 1, 2, 3, 4, and 5 mg/L, respectively, against A. subpictus

  17. Efficacy of ivermectin for the treatment of head lice (Pediculosis capitis).

    PubMed

    Glaziou, P; Nyguyen, L N; Moulia-Pelat, J P; Cartel, J L; Martin, P M

    1994-09-01

    Twenty six male and female patients aged 5 to 17 years who had head lice infestation confirmed by eggs presence and received treatments with a single 200 mu/kg oral dose of ivermectin in open fashion. At day 14 after treatment, 20 responded to the treatment (77%), and 6 patients (23%) presented with a complete disappearance of eggs and all clinical symptoms. At day 28, 7 patients were healed (27%), but 4 patients of the 6 healed at day 14 presented with signs of reinfestation. This study suggests that ivermectin is a promising treatment of head lice, and a second dose at day 10 should be appropriate for a further comparative trial. PMID:7899799

  18. Ovicidal and adulticidal activities of Origanum majorana essential oil constituents against insecticide-susceptible and pyrethroid/malathion-resistant Pediculus humanus capitis (Anoplura: Pediculidae).

    PubMed

    Yang, Young-Cheol; Lee, Si Hyeock; Clark, J Marshall; Ahn, Young-Joon

    2009-03-25

    The toxicity of essential oil constituents from marjoram, Origanum majorana, to eggs and adult females of the susceptible KR-HL and dual malathion- and permethrin-resistant BR-HL strains of human head louse, Pediculus humanus capitis, was examined using contact + fumigant mortality bioassay. Results were compared with those following treatment with two pyrethroid pediculicides, d-phenothrin or pyrethrum. As judged by the lethal time to 50% mortality (LT(50)) values at the exposure rate of 0.25 mg/cm(2), 1,8-cineole (14.1 min) was the most toxic compound, followed by linalool (15.4 min) to KR-HL females. These compounds were faster acting than either d-phenothrin (24.1 min) or pyrethrum (33.4 min). Based on the lethal concentration causing 50% mortality (LC(50)) values, (-)-camphor (0.022 mg/cm(2)) was the most toxic compound, followed by linalool (0.035 mg/cm(2)), (-)-terpinen-4-ol (0.040 mg/cm(2)), alpha-terpineol (0.045 mg/cm(2)), and 1,8-cineole (0.068 mg/cm(2)) against KR-HL females. These monoterpenoids were less toxic than either d-phenothrin (LC(50), 0.0015 mg/cm(2)) or pyrethrum (0.0013 mg/cm(2)). However, the toxicities of these monoterpenoids were almost identical against females from either of the two strains, even though the BR-HL females exhibited high levels of resistance to d-phenothrin [resistance ratio (RR), 667] and pyrethrum (RR, 754). After a 24 h exposure to linalool, BR-HL egg hatch was inhibited 100 and 84% at 0.25 or 0.125 mg/cm(2), respectively, while (-)-terpinen-4-ol caused 94 and 69% inhibition of egg hatch at 0.25 and 0.125 mg/cm(2). alpha-Terpineol caused 88 and 76% inhibition of egg hatch at 0.5 and 0.25 mg/cm(2), respectively. Thus, certain monoterpenoids from O. majorana essential oil, particularly linalool, (-)-terpinen-4-ol and alpha-terpineol, merit further study as potential pediculicides and ovicides for the control of insecticide-resistant P. h. capitis populations as fumigants with contact action. PMID:19292466

  19. Examining the prevalence rate of Pediculus capitis infestation according to sex and social factors in primary school children

    PubMed Central

    Doroodgar, Abbas; Sadr, Fakhraddin; Doroodgar, Masoud; Doroodgar, Moein; Sayyah, Mansour

    2014-01-01

    Objective To determine the prevalence rate of head louse infestation among elementary students, and examine the associated factors with infection in the city of Aran and Bidgol. Methods A total of 19 boys' and girls' primary schools were selected by multistage, systematic random sampling. Overall, 3 590 students were examined for head lice infestation in urban areas of Aran and Bidgol during 2008. The diagnosis was based on live louse or nit on the scalp of students. The students were screened by standard questionnaire and demographic data in addition to related information were obtained by interview and observation. The data were analyzed by SPSS software using chi-square and Fisher's exact tests. Results The mean age of students was (8.68±1.58) years ranging between 6-12 years. The total prevalence of head louse infestation was 0.47%. This rate was 0.42% and 0.05% in female and male, respectively. There was a significant association between pediculosis and sex, father's job, mother's education, access to bathroom in home, prior infection, drug use and nationality, respectively (P<0.05). Conclusions The results showed that pediculosis was not a major health priority among primary school in city of Aran and Bidgol. However, enhancing the knowledge of students about head lice infestation and the existence of health teachers in schools can play a significant role in disease control.

  20. Ovicidal effects of a neem seed extract preparation on eggs of body and head lice.

    PubMed

    Mehlhorn, Heinz; Abdel-Ghaffar, Fathy; Al-Rasheid, Khaled A S; Schmidt, Jürgen; Semmler, Margit

    2011-11-01

    The eggs (nits) of head and body lice (Pediculus humanus capitis, Pediculus humanus corporis) were incubated for 5, 10, 15, 20, 30 or 45 min into a neem seed extract contained in a fine shampoo formulation (e.g. Wash Away® Louse), which is known for its significant killing effects of larvae and adults of head lice. The aim of the study was to test whether the developmental stages inside the eggs are also killed after the incubation into the shampoo. It was found that an incubation time of only 5 min was sufficient to prohibit any hatching of larvae, whilst 93 ± 4% of the larvae in the untreated controls of body lice hatched respectively about 76% of the controls in the case of head lice. Apparently, the neem-based shampoo blocked the aeropyles of the eggs, thus preventing the embryos of both races of lice from accessing oxygen and from releasing carbon dioxide. Thus, this product offers a complete cure from head lice upon a single treatment, if the lice (motile stages, eggs) are fully covered for about 10 min. PMID:21484346

  1. Response of Pediculus humanus humanus (Pediculidae: Phthiraptera) to water or 70% ethanol immersion and determination of optimal times for measuring toxic effects.

    PubMed

    Mougabure Cueto, Gastón; Inés Picollo, María

    2010-05-01

    Human pediculosis is caused by Pediculus humanus humanus (Linnaeus 1758) and Pediculus humanus capitis (De Geer 1767). We studied the response of body lice to immersion in water and ethanol 70% and determined the optimal times for measuring knockdown and mortality. After immersion in water, all lice remained alive from 5 min to 22 h for both times of exposure. A low proportion of lice were affected after 2 min of immersion in ethanol in the 10-min exposure test, but recovered completely after 5 min. Different proportions of lice were affected between 2 and 7 h after immersion in ethanol, depending on the immersion time. However, a high proportion of lice recovered after 22 h. The results suggest that the optimal times for measuring early knockdown effects of insecticides are the 5-min to 7-h interval for water and 5-min to 1-h interval for ethanol. On the other hand, the best time for measuring mortality is 22 h after immersion. These results should improve the interpretations of the effects of pediculicides in immersion bioassays. PMID:20358227

  2. [Understanding mitochondrial genome fragmentation in parasitic lice (Insecta: Phthiraptera)].

    PubMed

    Dong, Wen-Ge; Guo, Xian-Guo; Jin, Dao-Chao; Xue, Shi-Peng; Qin, Feng; Simon, Song; Stephen, C Barker; Renfu, Shao

    2013-07-01

    Lice are obligate ectoparasites of mammals and birds. Extensive fragmentation of mitochondrial genomes has been found in some louse species in the families Pediculidae, Pthiridae, Philopteridae and Trichodectidae. For example, the mt genomes of human body louse (Pediculus humanus), head louse (Pediculus capitis), and public louse (Pthirus pubis) have 20, 20 and 14 mini-chromosomes, respectively. These mini-chromosomes might be the results of deletion and recombination of mt genes. The factors and mechanisms of mitochondrial genome fragmentation are currently unknown. The fragmentation might be the results of evolutionary selection or random genetic drift or it is probably related to the lack of mtSSB (mitochondrial single-strand DNA binding protein). Understanding the fragmentation of mitochondrial genomes is of significance for understanding the origin and evolution of mitochondria. This paper reviews the recent advances in the studies of mito-chondrial genome fragmentation in lice, including the phenomena of mitochondrial genome fragmentation, characteristics of fragmented mitochondrial genomes, and some factors and mechanisms possibly leading to the mitochondrial genome fragmentation of lice. Perspectives for future studies on fragmented mt genomes are also discussed. PMID:23853355

  3. A Study of Head Lice Infestation (Pediculosis Capitis) among Primary School Students in the Villages of Abadan in 2012.

    PubMed

    Salehi, Shayesteh; Ban, Maryam; Motaghi, Minoo

    2014-07-01

    Head lice contamination has a global distribution and it is regarded as a main health problem throughout the world. Given the importance of physical health of students and head lice prevalence at school age, we aimed to examine the rate of head lice contamination among primary school students in the villages of Abadan in 2012. In this descriptive study, 624 students were randomly selected from primary schools. The hair of all students under the study was examined by the researcher (community health nurse) and the result was registered in the checklist confidentially. Moreover, one questionnaire including personal and family information was filled out for each student. The obtained data were later analyzed in SPSS software, version 18, using statistical test Chi-square and central qualitative and distribution statistics. The frequency of lice contamination was 27 cases (4.33%) in total, all of whom were girls. Although the difference between the head lice contamination and gender was statistically significant (P=0.00), the difference between this contamination type and grade of students and their parents' education and fathers' occupation was not significance. The highest rate of contamination (6.73%) was, however, observed in fifth graders. All contaminations were seen in girls, which could be due to their longer hair or wearing scarf as compared with boys. Unfavorable health condition and regional hot weather can be effective as well. Therefore, it is essential to provide the students, especially girls, with health training. PMID:25349862

  4. A Study of Head Lice Infestation (Pediculosis Capitis) among Primary School Students in the Villages of Abadan in 2012

    PubMed Central

    Salehi, Shayesteh; Ban, Maryam; Motaghi, Minoo

    2014-01-01

    Head lice contamination has a global distribution and it is regarded as a main health problem throughout the world. Given the importance of physical health of students and head lice prevalence at school age, we aimed to examine the rate of head lice contamination among primary school students in the villages of Abadan in 2012. In this descriptive study, 624 students were randomly selected from primary schools. The hair of all students under the study was examined by the researcher (community health nurse) and the result was registered in the checklist confidentially. Moreover, one questionnaire including personal and family information was filled out for each student. The obtained data were later analyzed in SPSS software, version 18, using statistical test Chi-square and central qualitative and distribution statistics. The frequency of lice contamination was 27 cases (4.33%) in total, all of whom were girls. Although the difference between the head lice contamination and gender was statistically significant (P=0.00), the difference between this contamination type and grade of students and their parents’ education and fathers’ occupation was not significance. The highest rate of contamination (6.73%) was, however, observed in fifth graders. All contaminations were seen in girls, which could be due to their longer hair or wearing scarf as compared with boys. Unfavorable health condition and regional hot weather can be effective as well. Therefore, it is essential to provide the students, especially girls, with health training. PMID:25349862

  5. Of lice and math: using models to understand and control populations of head lice.

    PubMed

    Laguna, María Fabiana; Laguna, Mara Fabiana; Risau-Gusman, Sebastián

    2011-01-01

    In this paper we use detailed data about the biology of the head louse (pediculus humanus capitis) to build a model of the evolution of head lice colonies. Using theory and computer simulations, we show that the model can be used to assess the impact of the various strategies usually applied to eradicate head lice, both conscious (treatments) and unconscious (grooming). In the case of treatments, we study the difference in performance that arises when they are applied in systematic and non-systematic ways. Using some reasonable simplifying assumptions (as random mixing of human groups and the same mobility for all life stages of head lice other than eggs) we model the contagion of pediculosis using only one additional parameter. It is shown that this parameter can be tuned to obtain collective infestations whose characteristics are compatible with what is given in the literature on real infestations. We analyze two scenarios: One where group members begin treatment when a similar number of lice are present in each head, and another where there is one individual who starts treatment with a much larger threshold ("superspreader"). For both cases we assess the impact of several collective strategies of treatment. PMID:21799752

  6. Of Lice and Math: Using Models to Understand and Control Populations of Head Lice

    PubMed Central

    Laguna, Mara Fabiana; Risau-Gusman, Sebastián

    2011-01-01

    In this paper we use detailed data about the biology of the head louse (pediculus humanus capitis) to build a model of the evolution of head lice colonies. Using theory and computer simulations, we show that the model can be used to assess the impact of the various strategies usually applied to eradicate head lice, both conscious (treatments) and unconscious (grooming). In the case of treatments, we study the difference in performance that arises when they are applied in systematic and non-systematic ways. Using some reasonable simplifying assumptions (as random mixing of human groups and the same mobility for all life stages of head lice other than eggs) we model the contagion of pediculosis using only one additional parameter. It is shown that this parameter can be tuned to obtain collective infestations whose characteristics are compatible with what is given in the literature on real infestations. We analyze two scenarios: One where group members begin treatment when a similar number of lice are present in each head, and another where there is one individual who starts treatment with a much larger threshold (“superspreader”). For both cases we assess the impact of several collective strategies of treatment. PMID:21799752

  7. Treatment of head lice.

    PubMed

    Diamantis, Stephanie A; Morrell, Dean S; Burkhart, Craig N

    2009-01-01

    Pediculosis capitis, or head lice, is a common infestation among children worldwide. Multiple therapies exist for the treatment of this condition, including topical pediculicides and oral medications. When used in combination with environmental decontamination, these drugs can be very effective in eradicating head lice infestation without significant adverse events. The present study discusses the use of available over-the-counter and prescription treatments, including pyrethroids and permethrin, lindane, malathion, ivermectin, and trimethoprim-sulfamethoxazole, in the treatment of head lice. PMID:19580574

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

    PubMed

    Lindh, Johan; Magnusson, Måns; Grünewald, Maria; Hulth, Anette

    2012-01-01

    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. PMID:23144923

  9. Heteroplasmy in the Mitochondrial Genomes of Human Lice and Ticks Revealed by High Throughput Sequencing

    PubMed Central

    Xiong, Haoyu; Barker, Stephen C.; Burger, Thomas D.; Raoult, Didier; Shao, Renfu

    2013-01-01

    The typical mitochondrial (mt) genomes of bilateral animals consist of 37 genes on a single circular chromosome. The mt genomes of the human body louse, Pediculus humanus, and the human head louse, Pediculus capitis, however, are extensively fragmented and contain 20 minichromosomes, with one to three genes on each minichromosome. Heteroplasmy, i.e. nucleotide polymorphisms in the mt genome within individuals, has been shown to be significantly higher in the mt cox1 gene of human lice than in humans and other animals that have the typical mt genomes. To understand whether the extent of heteroplasmy in human lice is associated with mt genome fragmentation, we sequenced the entire coding regions of all of the mt minichromosomes of six human body lice and six human head lice from Ethiopia, China and France with an Illumina HiSeq platform. For comparison, we also sequenced the entire coding regions of the mt genomes of seven species of ticks, which have the typical mitochondrial genome organization of bilateral animals. We found that the level of heteroplasmy varies significantly both among the human lice and among the ticks. The human lice from Ethiopia have significantly higher level of heteroplasmy than those from China and France (Pt<0.05). The tick, Amblyomma cajennense, has significantly higher level of heteroplasmy than other ticks (Pt<0.05). Our results indicate that heteroplasmy level can be substantially variable within a species and among closely related species, and does not appear to be determined by single factors such as genome fragmentation. PMID:24058467

  10. Heteroplasmy in the mitochondrial genomes of human lice and ticks revealed by high throughput sequencing.

    PubMed

    Xiong, Haoyu; Barker, Stephen C; Burger, Thomas D; Raoult, Didier; Shao, Renfu

    2013-01-01

    The typical mitochondrial (mt) genomes of bilateral animals consist of 37 genes on a single circular chromosome. The mt genomes of the human body louse, Pediculus humanus, and the human head louse, Pediculus capitis, however, are extensively fragmented and contain 20 minichromosomes, with one to three genes on each minichromosome. Heteroplasmy, i.e. nucleotide polymorphisms in the mt genome within individuals, has been shown to be significantly higher in the mt cox1 gene of human lice than in humans and other animals that have the typical mt genomes. To understand whether the extent of heteroplasmy in human lice is associated with mt genome fragmentation, we sequenced the entire coding regions of all of the mt minichromosomes of six human body lice and six human head lice from Ethiopia, China and France with an Illumina HiSeq platform. For comparison, we also sequenced the entire coding regions of the mt genomes of seven species of ticks, which have the typical mitochondrial genome organization of bilateral animals. We found that the level of heteroplasmy varies significantly both among the human lice and among the ticks. The human lice from Ethiopia have significantly higher level of heteroplasmy than those from China and France (Pt<0.05). The tick, Amblyomma cajennense, has significantly higher level of heteroplasmy than other ticks (Pt<0.05). Our results indicate that heteroplasmy level can be substantially variable within a species and among closely related species, and does not appear to be determined by single factors such as genome fragmentation. PMID:24058467

  11. Epidemiology of Pediculosis capitis in elementary schools of Buenos Aires, Argentina.

    PubMed

    Toloza, Ariel; Vassena, Claudia; Gallardo, Anabella; González-Audino, Paola; Picollo, María Inés

    2009-06-01

    The infestation with the human obligate ectoparasite Pediculus humanus capitis De Geer is a common public health problem affecting mainly schoolchildren worldwide. The aim of the present study was to investigate the infestation levels of head lice in elementary schools from Buenos Aires with resistant levels to permethrin >100. A total of 1,856 children aged 3-13 years old from eight selected elementary schools were examined for head lice. Pediculosis was observed in all the studied schools. The overall infestation rate was 29.7%. Girls were statistically significant more infested than boys, with infestation rate values of 36.1% and 26.7%, respectively (P < 0.0001). Only 42 of the infested girls (12%) and 23 of the infested boys (11.4%) had >10 lice on their hair. The proportions of infested children-both girls and boys-in each age group were not found to differ significantly from one another. The infestation rate among schools varied from 19.12% to 42.74%. This indicated that pediculosis is relatively common in elementary schools from Buenos Aires, and those levels are of epidemic importance. The differences of pediculosis among the studied schools could be explained by the different control strategies applied by parents or advisors to eradicate head lice. PMID:19148682

  12. Severe head lice infestation in an Andean mummy of Arica, Chile.

    PubMed

    Arriaza, Bernardo; Orellana, Nancy C; Barbosa, Helene S; Menna-Barreto, Rubem F S; Araújo, Adauto; Standen, Vivien

    2012-04-01

    Pediculus humanus capitis is an ancient human parasite, probably inherited from pre-hominid times. Infestation appears as a recurrent health problem throughout history, including in pre-Columbian populations. Here, we describe and discuss the occurrence of pre-Columbian pediculosis in the Andean region of the Atacama Desert. Using a light microscope and scanning electron microscopy, we studied a highly infested Maitas Chiribaya mummy from Arica in northern Chile dating to 670-990 calibrated years A.D. The scalp and hair of the mummy were almost completely covered by nits and adult head lice. Low- and high-vacuum scanning electron microscopy revealed a well-preserved morphology of the eggs. In addition, the excellent preservation of the nearly 1,000-yr-old adult head lice allowed us to observe and characterize the head, antennae, thorax, abdomen, and legs. Leg segmentation, abdominal spiracles, and sexual dimorphism also were clearly observed. The preservation of the ectoparasites allowed us to examine the micromorphology using scanning electron microscopy; the opercula, aeropyles, and spiracles were clearly visible. This case study provides strong evidence that head lice were a common nuisance for Andean farmers and herders. Head lice are transmitted by direct head-to-head contact; thus, this ancient farmer and herder was potentially infesting other people. The present study contributes to the body of research focusing on lice in ancient populations. PMID:22010860

  13. In vitro screening of anti-lice activity of Pongamia pinnata leaves.

    PubMed

    Anbu Jeba Sunilson, John Samuel; Suraj, Radhamani; Rejitha, Gopinath; Anandarajagopal, Kalusalingam; Vimala, Anita Gnana Kumari Anbumani; Husain, Hj Azman

    2009-12-01

    Growing patterns of pediculocidal drug resistance towards head louse laid the foundation for research in exploring novel anti-lice agents from medicinal plants. In the present study, various extracts of Pongamia pinnata leaves were tested against the head louse Pediculus humanus capitis. A filter paper diffusion method was conducted for determining the potential pediculocidal and ovicidal activity of chloroform, petroleum ether, methanol, and water extracts of P. pinnata leaves. The findings revealed that petroleum ether extracts possess excellent anti-lice activity with values ranging between 50.3% and 100% where as chloroform and methanol extracts showed moderate pediculocidal effects. The chloroform and methanol extracts were also successful in inhibiting nymph emergence and the petroleum ether extract was the most effective with a complete inhibition of emergence. Water extract was devoid of both pediculocidal and ovicidal activities. All the results were well comparable with benzoyl benzoate (25% w/v). These results showed the prospect of using P. pinnata leave extracts against P. humanus capitis in difficult situations of emergence of resistance to synthetic anti-lice agents. PMID:19967085

  14. Activity of increased specific and non-specific esterases and glutathione transferases associated with resistance to permethrin in pediculus humanus capitis (phthiraptera: pediculidae) from Argentina.

    PubMed

    Barrios, Silvia; Zerba, Eduardo; Picollo, Maria I; Audino, Paola Gonzalez

    2010-01-01

    Enhanced metabolism by oxidative enzymes is a major cause of pyrethroid resistance in insects. In this work, we evaluated the role of specific and non-specific esterases in head louse populations from Buenos Aires with different levels of resistance to permethrin. As esterase activity is substrate-dependent, four different esters were used as unspecific substrates in order to obtain a better characterization of the possible role of these enzymes in the resistance phenomenon. The unspecific substrates were phenylthioacetate, 1- and 2-naphtyl-acetate, and p-nitrophenyl acetate. A 7-coumaryl permethrate was synthesized and used as a specific substrate to measure pyrethroid esterases by a very sensitive microfluorometric method. The results on pyrethroid esterase activity obtained with this substrate showed that these enzymes contribute to the detoxifying activity in resistant populations, although no correlation was found between pyrethroid esterase activity and resistance ratios. In this study, we established that the activity of esterase against specific and non-specific substrates is increased in pyrethroid-resistant populations of head lice from Buenos Aires. Also, dichlorodiphenyltrichloroethane (DDT) resistance values demonstrated that there is a DDT cross-resistance phenomenon in pyrethroid-resistant head louse populations and suggested that an alteration in the receptor of the nervous system (kdr gen) is a key factor of the resistance phenomena in these head louse populations. PMID:19921258

  15. Pediculosis capitis: an update.

    PubMed

    Madke, Bhushan; Khopkar, Uday

    2012-01-01

    Head louse infestation, or pediculosis capitis, caused by Pediculus humanus var. capitis, is a common health concern in pediatric age group. An itching of the scalp is the chief symptom, whereas presence of viable nits confirms the diagnosis of head louse infestation. Secondary bacterial infection with impetignization with cervical and occipital lymphadenopathy can complicate the clinical scenario with physician misdiagnosing pediculosis to a primary bacterial infection. Screening and treatment of all close contacts is necessary for an adequate management of pediculosis. Medical management of head louse infestation requires proper application of topical pediculicidal agents', chiefly permethrin lotion and wet combing with a fine toothcomb. Severe cases with high parasitic load justify the use of either oral cotrimoxazole or Ivermectin. Other described technique involves a single application of hot air for 30 minutes. Radical but culturally unacceptable method would be shaving of scalp in resistant cases. Environmental fogging with insecticides is neither necessary nor recommended. PMID:22772612

  16. A preliminary pilot survey on head lice, pediculosis in Sharkia Governorate and treatment of lice with natural plant extracts.

    PubMed

    El-Basheir, Zeinab M; Fouad, Mahmoud A H

    2002-12-01

    Twelve different representative areas in Sharkia Governorate were surveyed for head lice, Pediculus humanus capitis. The pre-valence was investigated among 120 houses containing 2,448 individual, with different age, sex and socioeconomic status. Examination was done by naked eye aided with hand-lens. A total of 137 individuals were infested. Infestation rates were higher in the rural areas with low socioeconomic levels, concrete houses with over-crowded family members. Children had significantly higher infestation rates than adults. Males had lower infestation rates than females. However, the hair length and permanent hair washing were the factors accounted for both age and sex difference in prevalence of pediculosis. Head lice infestations were found all over the year, but increased in summer and spring. One hundred infested patients (90 females and 10 males) with different aged and hair length were treated with tour mixed cream from plants Lawsonia alba L. (Henna). Trigonella faemum-gracanum (Fenugreek), Hibiscus cannabinus (Hibiscus) and Artemisia cina (Wormseed). The head lice completely disappeared within a week among those patients treated by henna mixed with aqueous extract of sheah (100%) or mixed with helba (75%) or with karkada (50%). PMID:12512805

  17. Spinosad: in pediculosis capitis.

    PubMed

    McCormack, Paul L

    2011-10-01

    Spinosad 0.9% suspension is a topical treatment for head-lice infestation (pediculosis capitis) that has been approved in the US as a prescription medicine. Spinosad is a natural mixture of the pediculicidal tetracyclic macrolides spinosyn A and spinosyn D. Spinosad 0.9% mainly interferes with nicotinic acetylcholine receptors in insects, thereby producing neuronal excitation that results in paralysis of lice from neuromuscular fatigue after extended periods of hyperexcitation. Spinosad 0.9% kills both permethrin-susceptible and permethrin-resistant populations of lice. It is also ovicidal, killing both eggs (nits) and lice. Systemic absorption was not detectable after a single topical application of spinosad 1.8% for 10 minutes in children. In randomized, evaluator-blind, multicenter clinical trials, topical spinosad 0.9% without nit combing was significantly more effective than permethrin 1% with nit combing in the eradication of head lice assessed 14 days after one or two treatments. The majority of subjects treated with spinosad 0.9% without nit combing required only a single treatment to eradicate head lice, while the majority of those treated with permethrin 1% with nit combing required two treatments. Spinosad was generally well tolerated in clinical trials, with no severe or serious adverse events. Cutaneous and ocular irritation were the most common adverse events. PMID:21834600

  18. Second-generation sequencing of entire mitochondrial coding-regions (∼15.4 kb) holds promise for study of the phylogeny and taxonomy of human body lice and head lice.

    PubMed

    Xiong, H; Campelo, D; Pollack, R J; Raoult, D; Shao, R; Alem, M; Ali, J; Bilcha, K; Barker, S C

    2014-08-01

    The Illumina Hiseq platform was used to sequence the entire mitochondrial coding-regions of 20 body lice, Pediculus humanus Linnaeus, and head lice, P. capitis De Geer (Phthiraptera: Pediculidae), from eight towns and cities in five countries: Ethiopia, France, China, Australia and the U.S.A. These data (∼310 kb) were used to see how much more informative entire mitochondrial coding-region sequences were than partial mitochondrial coding-region sequences, and thus to guide the design of future studies of the phylogeny, origin, evolution and taxonomy of body lice and head lice. Phylogenies were compared from entire coding-region sequences (∼15.4 kb), entire cox1 (∼1.5 kb), partial cox1 (∼700 bp) and partial cytb (∼600 bp) sequences. On the one hand, phylogenies from entire mitochondrial coding-region sequences (∼15.4 kb) were much more informative than phylogenies from entire cox1 sequences (∼1.5 kb) and partial gene sequences (∼600 to ∼700 bp). For example, 19 branches had > 95% bootstrap support in our maximum likelihood tree from the entire mitochondrial coding-regions (∼15.4 kb) whereas the tree from 700 bp cox1 had only two branches with bootstrap support > 95%. Yet, by contrast, partial cytb (∼600 bp) and partial cox1 (∼486 bp) sequences were sufficient to genotype lice to Clade A, B or C. The sequences of the mitochondrial genomes of the P. humanus, P. capitis and P. schaeffi Fahrenholz studied are in NCBI GenBank under the accession numbers KC660761-800, KC685631-6330, KC241882-97, EU219988-95, HM241895-8 and JX080388-407. PMID:25171606

  19. Hemocytes from Pediculus humanus humanus are hosts for human bacterial pathogens.

    PubMed

    Coulaud, Pierre-Julien; Lepolard, Catherine; Bechah, Yassina; Berenger, Jean-Michel; Raoult, Didier; Ghigo, Eric

    2014-01-01

    Pediculus humanus humanus is an human ectoparasite which represents a serious public health threat because it is vector for pathogenic bacteria. It is important to understand and identify where bacteria reside in human body lice to define new strategies to counterstroke the capacity of vectorization of the bacterial pathogens by body lice. It is known that phagocytes from vertebrates can be hosts or reservoirs for several microbes. Therefore, we wondered if Pediculus humanus humanus phagocytes could hide pathogens. In this study, we characterized the phagocytes from Pediculus humanus humanus and evaluated their contribution as hosts for human pathogens such as Rickettsia prowazekii, Bartonella Quintana, and Acinetobacter baumannii. PMID:25688336

  20. Hemocytes from Pediculus humanus humanus are hosts for human bacterial pathogens

    PubMed Central

    Coulaud, Pierre-Julien; Lepolard, Catherine; Bechah, Yassina; Berenger, Jean-Michel; Raoult, Didier; Ghigo, Eric

    2015-01-01

    Pediculus humanus humanus is an human ectoparasite which represents a serious public health threat because it is vector for pathogenic bacteria. It is important to understand and identify where bacteria reside in human body lice to define new strategies to counterstroke the capacity of vectorization of the bacterial pathogens by body lice. It is known that phagocytes from vertebrates can be hosts or reservoirs for several microbes. Therefore, we wondered if Pediculus humanus humanus phagocytes could hide pathogens. In this study, we characterized the phagocytes from Pediculus humanus humanus and evaluated their contribution as hosts for human pathogens such as Rickettsia prowazekii, Bartonella Quintana, and Acinetobacter baumannii. PMID:25688336

  1. White piedra and pediculosis capitis in the same patient.

    PubMed

    Marques, Silvio Alencar; Richini-Pereira, Virgínia Bodelão; Camargo, Rosângela Maria Pires de

    2012-01-01

    White piedra is a superficial mycosis caused by the genus Trichosporon. It is characterized by nodules on the hair shaft. Pediculosis capitis is caused by Pediculus humanus var. capitis of the suborder Anoplura. Whereas pediculosis is a common infestation, clinical reports of white piedra are rare. Molecular biology procedures identified T. inkin as the agent of white piedra in this case report. The authors present associations between the two diseases in the same patient in order to highlight their clinical differences. PMID:23044579

  2. A systematic literature review of pediculosis due to head lice in the Pacific Island Countries and Territories: what country specific research on head lice is needed?

    PubMed Central

    2014-01-01

    Background Lack of guidelines on control of pediculosis in the Solomon Islands led to a search for relevant evidence on head lice in the Pacific Island Countries and Territories (PICTs). The aim of this search was to systematically evaluate evidence in the peer reviewed literature on pediculosis due to head lice (Pediculus humanus var capitis) in the 22 PICTs from the perspective of its value in informing national guidelines and control strategies. Methods PubMed, Web of Science, CINAHL and Scopus were searched using the terms (pediculosis OR head lice) AND each of the 22 PICTs individually. PRISMA methodology was used. Exclusion criteria were: i) not on topic; ii) publications on pediculosis not relevant to the country of the particular search; iii) in grey literature. Results Of 24 publications identified, only 5 were included. Four related to treatment and one to epidemiology. None contained information relevant to informing national guidelines. Conclusions Current local evidence on head lice in the PICTs is minimal and totally inadequate to guide any recommendations for treatment or control. We recommend that local research is required to generate evidence on: i) epidemiology; ii) knowledge, attitudes and practices of health care providers and community members; iii) efficacy of local commercially available pharmaceutical treatments and local customary treatments; iv) acceptability, accessibility and affordability of available treatment strategies; and iv) appropriate control strategies for families, groups and institutions. We also recommend that operational research be done by local researchers based in the PICTs, supported by experienced head lice researchers, using a two way research capacity building model. PMID:24962507

  3. A new ivermectin formulation topically kills permethrin-resistant human head lice (Anoplura: Pediculidae).

    PubMed

    Strycharz, Joseph P; Yoon, Kyong Sup; Clark, J Marshall

    2008-01-01

    This study examines the effectiveness of a new ivermectin formulation for the topical treatment of the human head louse, Pediculus humanus capitis De Geer (Anoplura: Pediculidae). Permethrin-resistant lice originally obtained from south Florida and maintained on an in vitro rearing system were 100% susceptible to ivermectin formulations by using a semiclinical hair tuft bioassay. The formulation was 100% effective at killing lice using 1, 0.5, and 0.25% ivermectin concentrations after 10-min exposures. As judged by the lethal time (LT)50 and LT95 values, 0.5% formulated ivermectin was 3.8 and 3.2 times faster at killing lice, respectively, than 0.5% nonformulated ivermectin, indicating that the formulation may facilitate the penetration of ivermectin into the louse. The hair tuft-based bioassay in conjunction with the in vitro rearing system provides a standardized method to assess the comparative efficacy of pediculicide formulations in a reproducible format that mimics the exposure scenario that occurs on the human scalp. PMID:18283945

  4. A pediculid case: autosensitization dermatitis caused by pediculosis capitis.

    PubMed

    Takcı, Zennure; Tekin, Ozlem; Karadağ, Ayşe Serap

    2012-01-01

    Pediculosis capitis is a worldwide infestation caused by Pediculus humanus capitis ectoparasite that only lives on the hairs of the scalp. As a result of severe itching excoriation, secondary bacterial infection, cervical and occipital lymphadenopathy are seen frequently where, sometimes bite reaction, viral exanthema mimicking hypersensitivity eruption and conjunctivitis may occur. Hereby, with the presentation of a quite rarely seen pediculid case, characterized with common autosensitization dermatitis as an -id reaction to pediculosis capitis, the importance of exploring the source of the infection and/or infestation on the patients who have presented with generalized pruritic maculopapular eruption, is emphasized. PMID:23169166

  5. Tinea capitis

    MedlinePlus

    ... special test that uses a lamp called a Wood's lamp can help diagnose a fungal scalp infection. ... scalp; Ringworm - scalp Images Ringworm of the scalp Wood's lamp test - of the scalp Ringworm, tinea capitis - ...

  6. Tinea capitis

    MedlinePlus

    ... tinea capitis. A special test that uses a lamp called a Wood's lamp can help diagnose a fungal scalp infection. Your ... ketoconazole or selenium sulfide. Shampooing may slow or stop the spread of infection, but it does not ...

  7. Wet combing for the eradication of head lice.

    PubMed

    2013-03-01

    Manual removal (using conditioner and comb or a wet comb) can be used in the treatment of head lice. Head lice infestation (Pediculosis humanus capitis) is a common problem. It is diagnosed by visualising the lice. As half of people infested with head lice will not scratch, all people in contact with a person affected with head lice should be manually checked for infestations. Wet combing is easily and safely performed at home, but persistence is needed. This article describes the process of head lice removal using a wet comb. It has NHMRC Level 2 evidence of efficacy and no serious adverse effects have been reported. PMID:23529522

  8. Pyrethrins combined with piperonyl butoxide (RID) vs 1% permethrin (NIX) in the treatment of head lice.

    PubMed

    Carson, D S; Tribble, P W; Weart, C W

    1988-07-01

    In a randomized controlled trial, 58 subjects were treated for Pediculus humanus var capitis with either pyrethrins combined with piperonyl butoxide (RID, Pfizer Inc, New York) or 1% permethrin (NIX, Burroughs Wellcome Co, Research Triangle Park, NC); 31 subjects received RID and 27 subjects received NIX. Both products were applied according to manufacturer's directions so that NIX was applied only on the first visit and RID was applied on the first visit and again seven days later. After each treatment with a pediculicide, the comb supplied by the manufacturer was used to remove nits. Seven days after the initial visit, NIX was determined to be significantly better than RID for eradicating the lice infestation. Of the 27 subjects receiving NIX, 26 were live free vs 14 of the 31 RID-treated subjects. At day 14, there was no statistically significant difference in the treatments (27 of 27 NIX-treated vs 29 of 31 RID-treated subjects were lice free). The RID comb was superior to the NIX comb for nit removal. Both treatments were effective and well tolerated, and no subject experienced adverse reactions. PMID:3381781

  9. Clinical Practice Update: Pediculosis Capitis.

    PubMed

    Bohl, Brittany; Evetts, Jessica; McClain, Kymberli; Rosenauer, Amanda; Stellitano, Emily

    2015-01-01

    A review of the current evidence on primary treatment modalities of head lice demonstrates increasing resistance to current regimens. New and alternative therapies are now available. A treatment algorithm was created to address safety and efficacy of treatments, as well as to guide clinicians through navigation of the regimens. Through an online journal search, 59 articles were selected for the review. Literature searches were performed through PubMed, Medline, Ebsco Host, and CINAHL, with key search words of "Pediculosis capitis" and "head lice" in the title, abstract, and index. Meta-analyses and controlled clinical trials were viewed with greater weight if they had a large sample size, were statistically significant, and did not allude to bias. When resistant infestations are well-documented in a locality, changes to the treatment regimen are indicated, and alternative treatments should be considered. Recent studies and U.S. Food and Drug Administration (FDA) approvals have changed the available treatment options for Pediculosis capitis, including benzyl alcohol, topical ivermectin, spinosad, and the LouseBuster. Further, environmental management and prevention measures should be taken to avoid reinfestation and to prevent the spread of head lice. Continued study is recommended to establish long-term safety of new and alternative agents. PMID:26665422

  10. Evidence that clade A and clade B head lice live in sympatry and recombine in Algeria.

    PubMed

    Boutellis, A; Bitam, I; Fekir, K; Mana, N; Raoult, D

    2015-03-01

    Pediculus humanus L. (Psocodea: Pediculidae) can be characterized into three deeply divergent lineages (clades) based on mitochondrial DNA. Clade A consists of both head lice and clothing lice and is distributed worldwide. Clade B consists of head lice only and is mainly found in North and Central America, and in western Europe and Australia. Clade C, which consists only of head lice, is found in Ethiopia, Nepal and Senegal. Twenty-six head lice collected from pupils at different elementary schools in two localities in Algiers (Algeria) were analysed using molecular methods for genotyping lice (cytochrome b and the multi-spacer typing (MST) method. For the first time, we found clade B head lice in Africa living in sympatry with clade A head lice. The phylogenetic analysis of the concatenated sequences of these populations of head lice showed that clade A and clade B head lice had recombined, suggesting that interbreeding occurs when lice live in sympatry. PMID:25346378

  11. Efficacy of a grapefruit extract on head lice: a clinical trial.

    PubMed

    Abdel-Ghaffar, Fathy; Semmler, Margit; Al-Rasheid, Khaled; Klimpel, Sven; Mehlhorn, Heinz

    2010-01-01

    Twenty children aging 2-9 years old--four boys with short hair and 16 girls with long hair--were included in a clinical test on the efficacy of a product against head lice (Pediculus humanus capitis). Their hair were exposed to Licatack, which is a recently developed new anti-louse medicinal product containing extracts of grapefruits besides high quality shampoo components. Prior to this field trial, the product Licatack was tested dermatologically to be skin safe receiving the grade "very good". The children's mothers combed the kids prior to the start of the test in order to confirm that they were all lice-infested. The obtained lice were used for in vitro tests. All children were heavily infested. After combing and preservation of the living lice, the hair was wet with tap water. Then, 50 ml of the Licatack shampoo was placed onto the top of each child's head. Then, the mothers distributed the rather fluid product all over the hair thoroughly from their base at the skin until the free end. During this process, a type of massage, the product became foamy and it was easily recognized where the product covered the hair, thus, avoiding untreated spots. The hair of half of the treated children were washed with tap water after 10 min of exposition; while in the other half of the children, the exposition period was prolonged to 20 min before washing. When combing the kids with a metal louse comb after the washing, the lice were found immobile and they did not recover during the following observation period of 4 h. Only two lice from the group with an exposition time of only 10 min showed some slight leg movements after they had been combed off, but they died within the next 2 h. Thus, this new anti-louse medicinal product has a very quick and efficient activity besides its advantages of being non-inflammable, skin safe, and nice smelling. None of the kids claimed any burning at the skin or other side effects, although the skin showed, prior to treatment, lots of scars

  12. The origin and distribution of human lice in the world.

    PubMed

    Boutellis, Amina; Abi-Rached, Laurent; Raoult, Didier

    2014-04-01

    Two genera of lice parasitize humans: Pthirus and Pediculus. The latter is of significant public health importance and comprises two ecotypes: the body louse and the head louse. These ecotypes are morphologically and genetically notably similar; the body louse is responsible for three infectious diseases: Louse-borne epidemic typhus, relapsing fever, and trench fever. Mitochondrial DNA studies have shown that there are three obviously divergent clades of head lice (A, B and C), and only one clade of body lice is shared with head lice (clade A). Each clade has a unique geographic distribution. Lice have been parasitizing humans for millions of years and likely dispersed throughout the World with the human migrations out of Africa, so they can be good markers for studying human evolution. Here, we present an overview of the origin of human lice and their role in vector pathogenic bacteria that caused epidemics, and we review the association between lice clades and human migrations. PMID:24524985

  13. Evolution of Extensively Fragmented Mitochondrial Genomes in the Lice of Humans

    PubMed Central

    Shao, Renfu; Zhu, Xing-Quan; Barker, Stephen C.; Herd, Kate

    2012-01-01

    Bilateral animals are featured by an extremely compact mitochondrial (mt) genome with 37 genes on a single circular chromosome. The human body louse, Pediculus humanus, however, has its mt genes on 20 minichromosomes. We sequenced the mt genomes of two other human lice: the head louse, P. capitis, and the pubic louse, Pthirus pubis. Comparison among the three human lice revealed the presence of fragmented mt genomes in their most recent common ancestor, which lived ∼7 Ma. The head louse has exactly the same set of mt minichromosomes as the body louse, indicating that the number of minichromosomes, and the gene content and gene arrangement in each minichromosome have remained unchanged since the body louse evolved from the head louse ∼107,000 years ago. The pubic louse has the same pattern of one protein-coding or rRNA gene per minichromosome (except one minichromosome with two protein-coding genes, atp6 and atp8) as the head louse and the body louse. This pattern is apparently ancestral to all human lice and has been stable for at least 7 Myr. Most tRNA genes of the pubic louse, however, are on different minichromosomes when compared with their counterparts in the head louse and the body louse. It is evident that rearrangement of four tRNA genes (for leucine, arginine and glycine) was due to gene-identity switch by point mutation at the third anticodon position or by homologous recombination, whereas rearrangement of other tRNA genes was by gene translocation between minichromosomes, likely caused by minichromosome split via gene degeneration and deletion. PMID:23042553

  14. Evolution of extensively fragmented mitochondrial genomes in the lice of humans.

    PubMed

    Shao, Renfu; Zhu, Xing-Quan; Barker, Stephen C; Herd, Kate

    2012-01-01

    Bilateral animals are featured by an extremely compact mitochondrial (mt) genome with 37 genes on a single circular chromosome. The human body louse, Pediculus humanus, however, has its mt genes on 20 minichromosomes. We sequenced the mt genomes of two other human lice: the head louse, P. capitis, and the pubic louse, Pthirus pubis. Comparison among the three human lice revealed the presence of fragmented mt genomes in their most recent common ancestor, which lived ∼7 Ma. The head louse has exactly the same set of mt minichromosomes as the body louse, indicating that the number of minichromosomes, and the gene content and gene arrangement in each minichromosome have remained unchanged since the body louse evolved from the head louse ∼107,000 years ago. The pubic louse has the same pattern of one protein-coding or rRNA gene per minichromosome (except one minichromosome with two protein-coding genes, atp6 and atp8) as the head louse and the body louse. This pattern is apparently ancestral to all human lice and has been stable for at least 7 Myr. Most tRNA genes of the pubic louse, however, are on different minichromosomes when compared with their counterparts in the head louse and the body louse. It is evident that rearrangement of four tRNA genes (for leucine, arginine and glycine) was due to gene-identity switch by point mutation at the third anticodon position or by homologous recombination, whereas rearrangement of other tRNA genes was by gene translocation between minichromosomes, likely caused by minichromosome split via gene degeneration and deletion. PMID:23042553

  15. Body lice

    MedlinePlus

    ... also get lice from infected clothing, towels, or bedding. Body lice are bigger than other types of ... last if you: Bathe regularly Wash clothes and bedding at least once a week Placing clothes in ...

  16. Head Lice

    MedlinePlus

    Head lice are parasitic wingless insects. They live on people's heads and feed on their blood. An adult louse ... Children ages 3-11 and their families get head lice most often. Personal hygiene has nothing to ...

  17. Head Lice

    MedlinePlus

    ... or prescription products. Over-the-counter shampoos and lotions containing pyrethrin (one brand name: Rid) or permethrin ( ... commonly used to treat head lice. Shampoos and lotions that kill head lice contain pesticides and other ...

  18. Head Lice

    MedlinePlus

    Head lice are parasitic wingless insects. They live on people's heads and feed on their blood. An adult ... Children ages 3-11 and their families get head lice most often. Personal hygiene has nothing to do ...

  19. Head lice.

    PubMed

    Devore, Cynthia D; Schutze, Gordon E

    2015-05-01

    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. PMID:25917986

  20. Pubic lice

    MedlinePlus

    ... Supplements Videos & Tools Español You Are Here: Home → Medical Encyclopedia → Pubic lice URL of this page: //medlineplus.gov/ency/article/000841.htm Pubic lice To use the sharing features on this page, please enable JavaScript. Pubic lice are tiny insects that infect the pubic hair area and lay ...

  1. Geographical distribution of pyrethroid resistance allele frequency in head lice (Phthiraptera: Pediculidae) from Argentina.

    PubMed

    Toloza, Ariel Ceferino; Ascunce, Marina S; Reed, David; Picollo, María Inés

    2014-01-01

    The human head louse, Pediculus humanus capitis De Geer (Phthiraptera: Pediculidae), is an obligate ectoparasite that causes pediculosis capitis and has parasitized humans since the beginning of humankind. Head louse infestations are widespread throughout the world and have been increasing since the early 1990s partially because of ineffective pediculicides. In Argentina, the overuse of products containing pyrethroids has led to the development of resistant louse populations. Pyrethroid insecticides act on the nervous system affecting voltage-sensitive sodium channels. Three point mutations at the corresponding amino acid sequence positions M815I, T917I, and L920F in the voltage-gated sodium channel gene are responsible for contributing to knockdown resistance (kdr). The management of pyrethroid resistance requires either early detection or the characterization of the mechanisms involved in head louse populations. In the current study, we estimated the distribution of kdr alleles in 154 head lice from six geographical regions of Argentina. Pyrethroid resistance kdr alleles were found in high frequencies ranging from 67 to 100%. Of these, 131 (85.1%) were homozygous resistant, 13 (8.4%) were homozygous susceptible, and 10 (6.5%) were heterozygous. Exact tests for the Hardy-Weinberg equilibrium for each location showed that genotype frequencies differed significantly from expectation in four of the six sites studied. These results show that pyrethroid resistance is well established reaching an overall frequency of 88%, thus close to fixation. With 30 yr of pyrethroid-based pediculicides use in Argentina, kdr resistance has evolved rapidly among these head louse populations. PMID:24605463

  2. Scalp Ringworm (Tinea Capitis)

    MedlinePlus

    ... rash and rashes clinical tools newsletter | contact Share | Ringworm, Scalp (Tinea Capitis) A parent's guide to condition and treatment ... fungal infection may be the cause. Overview Scalp ringworm (tinea capitis) is a common mild infection of ...

  3. Management and Treatment of Human Lice

    PubMed Central

    Sangaré, Abdoul Karim; Doumbo, Ogobara K.

    2016-01-01

    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. PMID:27529073

  4. Management and Treatment of Human Lice.

    PubMed

    Sangaré, Abdoul Karim; Doumbo, Ogobara K; Raoult, Didier

    2016-01-01

    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. PMID:27529073

  5. Head lice.

    PubMed

    Frankowski, Barbara L; Bocchini, Joseph A

    2010-08-01

    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. PMID:20660553

  6. Evidence that head and body lice on homeless persons have the same genotype.

    PubMed

    Veracx, Aurélie; Rivet, Romain; McCoy, Karen D; Brouqui, Philippe; Raoult, Didier

    2012-01-01

    Human head lice and body lice are morphologically and biologically similar but have distinct ecologies. They were shown to have almost the same basic genetic content (one gene is absent in head lice), but differentially express certain genes, presumably responsible for the vector competence. They are now believed to be ecotypes of the same species (Pediculus humanus) and based on mitochondrial studies, body lice have been included with head lice in one of three clades of human head lice (Clade A). Here, we tested whether head and body lice collected from the same host belong to the same population by examining highly polymorphic intergenic spacers. This study was performed on lice collected from five homeless persons living in the same shelter in which Clade A lice are prevalent. Lice were individually genotyped at four spacer loci. The genetic identity and diversity of lice from head and body populations were compared for each homeless person. Population genetic structure was tested between lice from the two body regions and between the lice from different host individuals.We found two pairs of head and body lice on the same homeless person with identical multi locus genotypes. No difference in genetic diversity was found between head and body louse populations and no evidence of significant structure between the louse populations was found, even after controlling for a possible effect of the host individual. More surprisingly, no structure was obvious between lice of different homeless persons.We believe that the head and body lice collected from our five subjects belong to the same population and are shared between people living in the same shelter. These findings confirm that head and body lice are two ecotypes of the same species and show the importance of implementing measures to prevent lice transmission between homeless people in shelters. PMID:23049889

  7. Pubic lice

    MedlinePlus

    ... Have sexual contact with an infected person Share bedding or clothing with an infected person ... are treating pubic lice: Wash all clothing and bedding in hot water. Spray items that cannot be ...

  8. Head Lice

    MedlinePlus

    ... on the hair, skin, or clothing. Finding lice eggs (nits). The eggs are yellow, brown, or tan and about the ... These seem glued to the hair. If the eggs have hatched, you will see clear shells. Swollen ...

  9. Host switching of human lice to new world monkeys in South America.

    PubMed

    Drali, Rezak; Abi-Rached, Laurent; Boutellis, Amina; Djossou, Félix; Barker, Stephen C; Raoult, Didier

    2016-04-01

    The coevolution between a host and its obligate parasite is exemplified in the sucking lice that infest primates. In the context of close lice-host partnerships and cospeciation, Pediculus mjobergi, the louse of New World primates, has long been puzzling because its morphology resembles that of human lice. To investigate the possibility that P. mjobergi was transmitted to monkeys from the first humans who set foot on the American continent thousands of years ago, we obtained and compared P. mjobergi lice collected from howler monkeys from Argentina to human lice gathered from a remote and isolated village in Amazonia that has escaped globalization. Morphological examinations were first conducted and verified the similarity between the monkey and human lice. The molecular characterization of several nuclear and mitochondrial genetic markers in the two types of lice revealed that one of the P. mjobergi specimens had a unique haplotype that clustered with the haplotypes of Amazonian head lice that are prevalent in tropical regions in the Americas, a natural habitat of New World monkeys. Because this phylogenetic group forms a separate branch within the clade of lice from humans that were of American origin, this finding indicates that human lice have transferred to New World monkeys. PMID:26867815

  10. Eradication of head lice with a single treatment.

    PubMed

    DiNapoli, J B; Austin, R D; Englender, S J; Gomez, M P; Barrett, J F

    1988-08-01

    Single application of Nix (permethrin 1% creme rinse) and Rid were compared as treatments for Pediculosis capitis in 435 patients, the majority of whom were children. Seven days after the treatment, 98 per cent of the permethrin-treated and 85 per cent of the Rid-treated patients were free of lice. At 14 days, prior to nit removal, 96 per cent of the permethrin-treated and 62 per cent of the Rid-treated patients were still lice free. Seventeen (7 per cent) permethrin-treated and 32 (16 per cent) Rid-treated patients were reported to have adverse experiences. PMID:3291623

  11. [Ectoparasites. Part 1: lice and fleas].

    PubMed

    Nenoff, P; Handrick, W; Krüger, C; Herrmann, J; Schmoranzer, B; Paasch, U

    2009-08-01

    Ectoparasites and epidermal parasitic skin diseases are a heterogeneous group of infections of the external layer of the skin. The most common forms world-wide are scabies, lice (Pediculosis capitis, corporis, vestimentorum and pubis), tungiasis and the hookworm-associated Larva migrans cutanea. The head louse is the most widespread parasite in children in Germany. The symptoms, apart from pruritus, eczematous skin eruptions and ictus reactions of the skin, are often unspecific and many differential diagnoses must be considered. Treatment of ectoparasites includes manual procedures, such as repeated cleansing and combing out of lice-infected hair and also local antiparasitic treatment with permethrin, pyrethrum extract, allethrin and dimeticon. Lindan which has been used for decades can no longer be used in medications after 2008 after a decision of the EU Commission. Failure of treatment of head lice can be a result of errors in the treatment which favor survival of the eggs, larvae or adults. This can be a result of too short reaction times and too economical use or unequal distribution of medications, excessive dilution due to wet hair or omitting repeated treatment stages. Additionally resistance of head lice to pyrethrum is a known phenomenon and has been reported in several countries. PMID:19633823

  12. Head Lice: Treatment

    MedlinePlus

    ... it may be necessary to use a second bottle. Pay special attention to instructions on the label ... or printed on the label. Nit (head lice egg) combs, often found in lice medicine packages, should ...

  13. Tinea capitis mimicking dissecting cellulitis.

    PubMed

    Torok, Rachel D; Bellet, Jane S

    2013-01-01

    Tinea capitis is a common disease of childhood that typically follows one of several clinical patterns. Our patient and several previously reported cases demonstrate the existence of a dissecting cellulitis-like presentation of tinea capitis. This variant should be recognized to prevent misdiagnosis of dissecting cellulitis and allow proper treatment to prevent scarring alopecia. PMID:24134312

  14. Prevalence and Risk Factors Associated with Pediculosis Capitis in an Impoverished Urban Community in Lima, Peru

    PubMed Central

    Lesshafft, Hannah; Baier, Andreas; Guerra, Humberto; Terashima, Angelica; Feldmeier, Hermann

    2013-01-01

    Background: Pediculosis capitis is a ubiquitous parasitic skin disease associated with intense pruritus of the scalp. In developing countries it frequently affects children and adults, but epidemiological data at the community level are rare. Objectives: To assess prevalence and risk factors associated with pediculosis capitis in a resource-poor community in Lima, Peru. Materials and Methods: In total, 736 persons living in 199 households in a circumscribed neighbourhood were examined for head lice and nits by visual inspection. At the same time, socio-demographic data were collected using a structured questionnaire. Variables associated with pediculosis were identified by performing a bivariate analysis, followed by a multivariate logistic regression analysis. Results: Prevalence of pediculosis capitis was 9.1% (95% confidence interval (CI): 7.0-11.2 %) in the general population and 19.9% (CI: 15.4-24.4%) in children ≤15 years of age. Multivariate analysis showed that pediculosis capitis was significantly associated with age ≤ 15 years (OR: 16.85; CI:7.42-38.24), female sex (OR: 2.84; CI: 1.58-5.12), household size of >4 persons (OR: 1.98; CI: 1.11-3.55), low quality of house construction material (OR:2.22; CI: 1.20-4.12), and presence of animals in the household (OR: 1.94; CI: 1.11-3.39). Conclusion: Pediculosis capitis was a very common disease in the studied community in Lima, Peru. Our logistic regression analysis affirms that young age is the most important risk factor for pediculosis capitis. Moreover, female sex, large household size, living in wooden houses and the presence of animals were identified as being significantly associated with head lice infestation. PMID:24672174

  15. Tinea Capitis in Infants

    PubMed Central

    Michaels, Brent D.

    2012-01-01

    Tinea capitis is a reasonably common infection among the pediatric population; however, it is still a relatively rare entity among infants less than one year of age. As such, a high index of suspicion is necessary for diagnosis among infants and an appropriate diagnostic work up should be employed in any case where a dermatophyte infection is suspected. Several methods are available for diagnosis. In addition, proper identification of the specific dermatophyte genera involved should be considered as treatment options may be altered based on the causative pathogen identified. PMID:22468173

  16. Treatment of Pediculosis Capitis.

    PubMed

    Verma, Prashant; Namdeo, Chaitanya

    2015-01-01

    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. PMID:26120148

  17. Treatment of Pediculosis Capitis

    PubMed Central

    Verma, Prashant; Namdeo, Chaitanya

    2015-01-01

    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. PMID:26120148

  18. Differential gene expression in laboratory strains of human head and body lice when challenged with Bartonella quintana, a pathogenic bacterium.

    PubMed

    Previte, D; Olds, B P; Yoon, K; Sun, W; Muir, W; Paige, K N; Lee, S H; Clark, J; Koehler, J E; Pittendrigh, B R

    2014-04-01

    Human head and body lice are obligatory hematophagous ectoparasites that belong to a single species, Pediculus humanus. Only body lice, however, are vectors of the infectious Gram-negative bacterium Bartonella quintana. Because of their near identical genomes, yet differential vector competence, head and body lice provide a unique model system to study the gain or loss of vector competence. Using our in vitro louse-rearing system, we infected head and body lice with blood containing B. quintana in order to detect both differences in the proliferation of B. quintana and transcriptional differences of immune-related genes in the lice. B. quintana proliferated rapidly in body lice at 6 days post-infection, but plateaued in head lice at 4 days post-infection. RNAseq and quantitative real-time PCR validation analyses determined gene expression differences. Eight immunoresponse genes were observed to be significantly different with many associated with the Toll pathway: Fibrinogen-like protein, Spaetzle, Defensin 1, Serpin, Scavenger receptor A and Apolipoporhrin 2. Our findings support the hypothesis that body lice, unlike head lice, fight infection from B. quintana only at the later stages of its proliferation. PMID:24404961

  19. Differential gene expression in laboratory strains of human head and body lice when challenged with Bartonella quintana, a pathogenic bacterium

    PubMed Central

    Previte, D.; Olds, B. P.; Yoon, K.; Sun, W.; Muir, W.; Paige, K. N.; Lee, S. H.; Clark, J.; Koehler, J. E.; Pittendrigh, B. R.

    2014-01-01

    Human head and body lice are obligatory hematophagous ectoparasites that belong to a single species, Pediculus humanus. Only body lice, however, are vectors of the infectious Gram-negative bacterium Bartonella quintana. Because of their near identical genomes, yet differential vector competence, head and body lice provide a unique model system to study the gain or loss of vector competence. Using our in vitro louse-rearing system, we infected head and body lice with blood containing B. quintana in order to detect both differences in the proliferation of B. quintana and transcriptional differences of immune-related genes in the lice. B. quintana proliferated rapidly in body lice at 6 days postinfection, but plateaued in head lice at 4 days postinfection. RNAseq and quantitative real-time PCR validation analyses determined gene expression differences. Eight immunoresponse genes were observed to be significantly different with many associated with the Toll pathway: Fibrinogen-like protein, Spaetzle, Defensin 1, Serpin, Scavenger receptor A and Apolipoporhrin 2. Our findings support the hypothesis that body lice, unlike head lice, fight infection from B. quintana only at the later stages of its proliferation. PMID:24404961

  20. Variable microsatellite loci for population genetic analysis of Old World monkey lice (Pedicinus sp.).

    PubMed

    Scholl, Katlyn; Allen, Julie M; Leendertz, Fabian H; Chapman, Colin A; Reed, David L

    2012-10-01

    Parasitic lice have been valuable informants of their host's evolutionary history because they complete their entire life cycle on the host and move between hosts primarily through direct host-to-host contact. Therefore, lice are confined to their hosts both in ecological and evolutionary time. Lice on great apes have been studied to examine details of their host's evolutionary history; however, species of Pedicinus, which parasitize the Old World monkeys, are less well known. We sampled lice from 2 groups of red colobus (Procolobus spp.) in Kibale National Park in Uganda and from red colobus and black and white colobus (Procolobus polycomos) in Taï National Park in Côte d'Ivoire. We used next-generation sequencing data analysis and the human body louse (Pediculus humanus humanus) genome to search for microsatellites for population genetic studies of Pedicinus lice. The 96 primer sets for microsatellite loci designed from the human body louse genome failed to amplify microsatellites in Pedicinus sp., perhaps due to the fast rate of evolution in parasitic lice. Of 63 microsatellites identified by next-generation sequencing data analysis of Pedicinus sp., 12 were variable among populations and 9 were variable within a single population. Our results suggest that these loci will be useful across the genus Pedicinus. We found that the lice in Uganda are not structured according to their hosts' social group; rather, 2 non-interbreeding populations of lice were found on both groups of red colobus. Because direct host-to-host contact is usually required for lice to move among hosts, these lice could be useful for identification and study of behavioral interactions between primate species. PMID:22509906

  1. Evolutionary relationships of "Candidatus Riesia spp.," endosymbiotic enterobacteriaceae living within hematophagous primate lice.

    PubMed

    Allen, Julie M; Reed, David L; Perotti, M Alejandra; Braig, Henk R

    2007-03-01

    The primary endosymbiotic bacteria from three species of parasitic primate lice were characterized molecularly. We have confirmed the characterization of the primary endosymbiont (P-endosymbiont) of the human head/body louse Pediculus humanus and provide new characterizations of the P-endosymbionts from Pediculus schaeffi from chimpanzees and Pthirus pubis, the pubic louse of humans. The endosymbionts show an average percent sequence divergence of 11 to 15% from the most closely related known bacterium "Candidatus Arsenophonus insecticola." We propose that two additional species be added to the genus "Candidatus Riesia." The new species proposed within "Candidatus Riesia" have sequence divergences of 3.4% and 10 to 12% based on uncorrected pairwise differences. Our Bayesian analysis shows that the branching pattern for the primary endosymbionts was the same as that for their louse hosts, suggesting a long coevolutionary history between primate lice and their primary endosymbionts. We used a calibration of 5.6 million years to date the divergence between endosymbionts from human and chimpanzee lice and estimated an evolutionary rate of nucleotide substitution of 0.67% per million years, which is 15 to 30 times faster than previous estimates calculated for Buchnera, the primary endosymbiont in aphids. Given the evidence for cospeciation with primate lice and the evidence for fast evolutionary rates, this lineage of endosymbiotic bacteria can be evaluated as a fast-evolving marker of both louse and primate evolutionary histories. PMID:17220259

  2. An unusual autopsy case of lethal hypothermia exacerbated by body lice-induced severe anemia.

    PubMed

    Nara, Akina; Nagai, Hisashi; Yamaguchi, Rutsuko; Makino, Yohsuke; Chiba, Fumiko; Yoshida, Ken-ichi; Yajima, Daisuke; Iwase, Hirotaro

    2016-05-01

    Pediculus humanus humanus (known as body lice) are commonly found in the folds of clothes, and can cause skin disorders when they feed on human blood, resulting in an itching sensation. Body lice are known as vectors of infectious diseases, including typhus, recurrent fever, and trench fever. An infestation with blood-sucking body lice induces severe cutaneous pruritus, and this skin disorder is known as "vagabond's disease." A body lice infestation is sometimes complicated with iron deficiency anemia. In the present case, a man in his late 70s died of lethal hypothermia in the outdoors during the winter season. The case history and autopsy findings revealed that the cause of the lethal hypothermia was iron deficiency anemia, which was associated with a prolonged infestation of blood-sucking body lice. Also, he had vagabond's disease because the skin on his body was abnormal and highly pigmented. This is an unusual autopsy case since the body lice contributed to the cause of the death. PMID:26384507

  3. The single mitochondrial chromosome typical of animals has evolved into 18 minichromosomes in the human body louse, Pediculus humanus

    PubMed Central

    Shao, Renfu; Kirkness, Ewen F.; Barker, Stephen C.

    2009-01-01

    The mitochondrial (mt) genomes of animals typically consist of a single circular chromosome that is ∼16-kb long and has 37 genes. Our analyses of the sequence reads from the Human Body Louse Genome Project and the patterns of gel electrophoresis and Southern hybridization revealed a novel type of mt genome in the sucking louse, Pediculus humanus. Instead of having all mt genes on a single chromosome, the 37 mt genes of this louse are on 18 minicircular chromosomes. Each minicircular chromosome is 3–4 kb long and has one to three genes. Minicircular mt chromosomes are also present in the four other species of sucking lice that we investigated, but not in chewing lice nor in the Psocoptera, to which sucking lice are most closely related. We also report unequivocal evidence for recombination between minicircular mt chromosomes in P. humanus and for sequence variation in mt genes generated by recombination. The advantages of a fragmented mt genome, if any, are currently unknown. Fragmentation of mt genome, however, has coevolved with blood feeding in the sucking lice. It will be of interest to explore whether or not life history features are associated with the evolution of fragmented chromosomes. PMID:19336451

  4. Treating Head Lice

    MedlinePlus

    ... and Prevention. Head lice are most common among preschool children attending child care, elementary school children, and ... Emergency Preparedness International Programs News & Events Training & Continuing Education Inspections & Compliance Federal, State & Local Officials Consumers Health ...

  5. Epidemiology of Lice

    ERIC Educational Resources Information Center

    Juranek, Dennis D.

    1977-01-01

    Research into the epidemiology of lice indicates that infestation is uncommon in blacks, more common in females than males, significantly higher in low income groups, and transmission is by way of articles of clothing. (JD)

  6. Pubic "Crab" Lice Treatment

    MedlinePlus

    ... on Facebook Tweet Share Compartir A lice-killing lotion containing 1% permethrin or a mousse containing pyrethrins ... persons who weigh less than 110 pounds. Malathion* lotion 0.5% (Ovide*) is a prescription medication that ...

  7. Pubic Lice (For Parents)

    MedlinePlus

    ... area with pubic hair, they are not good protection against pubic lice. A teen who is being ... knows how STDs can be spread (during anal, oral, or vaginal sex) and that these infections often don't have ...

  8. Mitochondrial genome deletions and minicircles are common in lice (Insecta: Phthiraptera)

    PubMed Central

    2011-01-01

    Background The gene composition, gene order and structure of the mitochondrial genome are remarkably stable across bilaterian animals. Lice (Insecta: Phthiraptera) are a major exception to this genomic stability in that the canonical single chromosome with 37 genes found in almost all other bilaterians has been lost in multiple lineages in favour of multiple, minicircular chromosomes with less than 37 genes on each chromosome. Results Minicircular mt genomes are found in six of the ten louse species examined to date and three types of minicircles were identified: heteroplasmic minicircles which coexist with full sized mt genomes (type 1); multigene chromosomes with short, simple control regions, we infer that the genome consists of several such chromosomes (type 2); and multiple, single to three gene chromosomes with large, complex control regions (type 3). Mapping minicircle types onto a phylogenetic tree of lice fails to show a pattern of their occurrence consistent with an evolutionary series of minicircle types. Analysis of the nuclear-encoded, mitochondrially-targetted genes inferred from the body louse, Pediculus, suggests that the loss of mitochondrial single-stranded binding protein (mtSSB) may be responsible for the presence of minicircles in at least species with the most derived type 3 minicircles (Pediculus, Damalinia). Conclusions Minicircular mt genomes are common in lice and appear to have arisen multiple times within the group. Life history adaptive explanations which attribute minicircular mt genomes in lice to the adoption of blood-feeding in the Anoplura are not supported by this expanded data set as minicircles are found in multiple non-blood feeding louse groups but are not found in the blood-feeding genus Heterodoxus. In contrast, a mechanist explanation based on the loss of mtSSB suggests that minicircles may be selectively favoured due to the incapacity of the mt replisome to synthesize long replicative products without mtSSB and thus the

  9. Present status of head louse (Pediculus capitis) infestation among school children in Yunlin County, Taiwan.

    PubMed

    Fan, P C; Chung, W C; Kuo, C L; Hsu, H M; Chow, C Y

    1991-04-01

    In December 1990, 35 children in one kindergarten; 7,870 children in twenty-six primary schools and 2,657 students in three junior high schools in Kou-Hu, Ku-Keng and Szu-Hu Districts in Yunlin County, Taiwan, were examined by naked eye observation (NEO) for head louse infestation. The overall infestation rate was 16%. The infestation rate was highest in Kou-Hu (25%) and lowest in Ku-Keng (8%). The rate was higher among primary school children (21%) than among junior high school students (2%). The infestation rate of girls (34% in primary school children and 4% in junior high school students) was higher than that of boys (9%, less than 1% respectively). Among the primary school children the rate was highest in girls in grade 5 (39%) and boys in grade 4 (14%). The lowest rates were in girls in grade 6 (27%) and in boys in grades 5 and 6 (6%). In junior high school students, the rate of grade 1 (4%) was higher than those of grade 2 (less than 1%) and 3 (less than 1%). PMID:2030521

  10. 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.

    PubMed

    Dehghanzadeh, Reza; Asghari-Jafarabadi, Mohammad; Salimian, Shahin; Asl Hashemi, Ahmad; Khayatzadeh, Simin

    2015-11-01

    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. PMID:26276644

  11. Alternative Splice in Alternative Lice.

    PubMed

    Tovar-Corona, Jaime M; Castillo-Morales, Atahualpa; Chen, Lu; Olds, Brett P; Clark, John M; Reynolds, Stuart E; Pittendrigh, Barry R; Feil, Edward J; Urrutia, Araxi O

    2015-10-01

    Genomic and transcriptomics analyses have revealed human head and body lice to be almost genetically identical; although con-specific, they nevertheless occupy distinct ecological niches and have differing feeding patterns. Most importantly, while head lice are not known to be vector competent, body lice can transmit three serious bacterial diseases; epidemictyphus, trench fever, and relapsing fever. In order to gain insights into the molecular bases for these differences, we analyzed alternative splicing (AS) using next-generation sequencing data for one strain of head lice and one strain of body lice. We identified a total of 3,598 AS events which were head or body lice specific. Exon skipping AS events were overrepresented among both head and body lice, whereas intron retention events were underrepresented in both. However, both the enrichment of exon skipping and the underrepresentation of intron retention are significantly stronger in body lice compared with head lice. Genes containing body louse-specific AS events were found to be significantly enriched for functions associated with development of the nervous system, salivary gland, trachea, and ovarian follicle cells, as well as regulation of transcription. In contrast, no functional categories were overrepresented among genes with head louse-specific AS events. Together, our results constitute the first evidence for transcript pool differences in head and body lice, providing insights into molecular adaptations that enabled human lice to adapt to clothing, and representing a powerful illustration of the pivotal role AS can play in functional adaptation. PMID:26169943

  12. Alternative Splice in Alternative Lice

    PubMed Central

    Tovar-Corona, Jaime M.; Castillo-Morales, Atahualpa; Chen, Lu; Olds, Brett P.; Clark, John M.; Reynolds, Stuart E.; Pittendrigh, Barry R.; Feil, Edward J.; Urrutia, Araxi O.

    2015-01-01

    Genomic and transcriptomics analyses have revealed human head and body lice to be almost genetically identical; although con-specific, they nevertheless occupy distinct ecological niches and have differing feeding patterns. Most importantly, while head lice are not known to be vector competent, body lice can transmit three serious bacterial diseases; epidemictyphus, trench fever, and relapsing fever. In order to gain insights into the molecular bases for these differences, we analyzed alternative splicing (AS) using next-generation sequencing data for one strain of head lice and one strain of body lice. We identified a total of 3,598 AS events which were head or body lice specific. Exon skipping AS events were overrepresented among both head and body lice, whereas intron retention events were underrepresented in both. However, both the enrichment of exon skipping and the underrepresentation of intron retention are significantly stronger in body lice compared with head lice. Genes containing body louse-specific AS events were found to be significantly enriched for functions associated with development of the nervous system, salivary gland, trachea, and ovarian follicle cells, as well as regulation of transcription. In contrast, no functional categories were overrepresented among genes with head louse-specific AS events. Together, our results constitute the first evidence for transcript pool differences in head and body lice, providing insights into molecular adaptations that enabled human lice to adapt to clothing, and representing a powerful illustration of the pivotal role AS can play in functional adaptation. PMID:26169943

  13. Assessment of topical versus oral ivermectin as a treatment for head lice.

    PubMed

    Ahmad, Hesham M; Abdel-Azim, Eman S; Abdel-Aziz, Rasha T

    2014-01-01

    Many medications are available for treatment of pediculosis capitis including ivermectin. Our aim is to compare the efficacy and safety of topical versus oral ivermectin in treatment of pediculosis capitis. Sixty-two patients with proved head lice infestation were included and divided into group I (31 patients; received single topical application of 1% ivermectin) and group II (31 patients; received single dose of oral ivermectin). Treatment was repeated after 1 week for nonresponders. At 1 week after treatment, the eradication rates and improvement of pruritus were significantly higher among patients who received topical than oral ivermectin. When a second treatment, topical or oral, was given to nonresponders, the cure rates of infestation and pruritus was 100% and 97% among patients treated with topical and oral ivermectin, respectively with no significant difference between the two groups. This study suggests that both topical and oral ivermectin demonstrate high efficacy and tolerability in treatment of pediculosis capitis. However, a single treatment with topical ivermectin provides significantly higher cure of infestation and faster relief of pruritus than oral ivermectin. In addition, whether topical or oral ivermectin is used to treat head lice, a second dose is required in some cases to ensure complete eradication. PMID:25041547

  14. Survey assessment on pediatricians’ attitudes on head lice management

    PubMed Central

    2013-01-01

    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

  15. Apes, lice and prehistory

    PubMed Central

    Weiss, Robin A

    2009-01-01

    Although most epidemic human infectious diseases are caused by recently introduced pathogens, cospeciation of parasite and host is commonplace for endemic infections. Occasional host infidelity, however, provides the endemic parasite with an opportunity to survive the potential extinction of its host. Such infidelity may account for the survival of certain types of human lice, and it is currently exemplified by viruses such as HIV. PMID:19232074

  16. What's bugging you? An update on the treatment of head lice infestation.

    PubMed

    Tebruegge, Marc; Pantazidou, Anastasia; Curtis, Nigel

    2011-02-01

    Head lice infestation (pediculosis capitis) is a common problem in paediatric practice. It can cause considerable distress to children and their families and may lead to bullying and social stigmatisation. Therapy with "conventional" topical pediculicides with neurotoxic mode of action-such as malathion, permethrin, phenothrin and carbaryl-is increasingly associated with treatment failure as a result of the emergence of resistance within the parasite population. This review provides an overview of the natural history, clinical symptoms and diagnosis of head lice infestation. It also discusses general management principles and summarises the current data on novel treatment strategies, including wet combing, dimeticone, isopropyl myristate, benzyl alcohol, plant-based compounds and oral medication. PMID:20688849

  17. High diversity and rapid diversification in the head louse, Pediculus humanus (Pediculidae: Phthiraptera).

    PubMed

    Ashfaq, Muhammad; Prosser, Sean; Nasir, Saima; Masood, Mariyam; Ratnasingham, Sujeevan; Hebert, Paul D N

    2015-01-01

    The study analyzes sequence variation of two mitochondrial genes (COI, cytb) in Pediculus humanus from three countries (Egypt, Pakistan, South Africa) that have received little prior attention, and integrates these results with prior data. Analysis indicates a maximum K2P distance of 10.3% among 960 COI sequences and 13.8% among 479 cytb sequences. Three analytical methods (BIN, PTP, ABGD) reveal five concordant OTUs for COI and cytb. Neighbor-Joining analysis of the COI sequences confirm five clusters; three corresponding to previously recognized mitochondrial clades A, B, C and two new clades, "D" and "E", showing 2.3% and 2.8% divergence from their nearest neighbors (NN). Cytb data corroborate five clusters showing that clades "D" and "E" are both 4.6% divergent from their respective NN clades. Phylogenetic analysis supports the monophyly of all clusters recovered by NJ analysis. Divergence time estimates suggest that the earliest split of P. humanus clades occurred slightly more than one million years ago (MYa) and the latest about 0.3 MYa. Sequence divergences in COI and cytb among the five clades of P. humanus are 10X those in their human host, a difference that likely reflects both rate acceleration and the acquisition of lice clades from several archaic hominid lineages. PMID:26373806

  18. High diversity and rapid diversification in the head louse, Pediculus humanus (Pediculidae: Phthiraptera)

    PubMed Central

    Ashfaq, Muhammad; Prosser, Sean; Nasir, Saima; Masood, Mariyam; Ratnasingham, Sujeevan; Hebert, Paul D. N.

    2015-01-01

    The study analyzes sequence variation of two mitochondrial genes (COI, cytb) in Pediculus humanus from three countries (Egypt, Pakistan, South Africa) that have received little prior attention, and integrates these results with prior data. Analysis indicates a maximum K2P distance of 10.3% among 960 COI sequences and 13.8% among 479 cytb sequences. Three analytical methods (BIN, PTP, ABGD) reveal five concordant OTUs for COI and cytb. Neighbor-Joining analysis of the COI sequences confirm five clusters; three corresponding to previously recognized mitochondrial clades A, B, C and two new clades, “D” and “E”, showing 2.3% and 2.8% divergence from their nearest neighbors (NN). Cytb data corroborate five clusters showing that clades “D” and “E” are both 4.6% divergent from their respective NN clades. Phylogenetic analysis supports the monophyly of all clusters recovered by NJ analysis. Divergence time estimates suggest that the earliest split of P. humanus clades occured slightly more than one million years ago (MYa) and the latest about 0.3 MYa. Sequence divergences in COI and cytb among the five clades of P. humanus are 10X those in their human host, a difference that likely reflects both rate acceleration and the acquisition of lice clades from several archaic hominid lineages. PMID:26373806

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

    PubMed

    Ibarra, Joanna; Fry, Frances; Wickenden, Clarice; Jenner, Maryan; Franks, Andrea

    2009-07-01

    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. PMID:19650551

  20. Head Lice: Malathion Frequently Asked Questions

    MedlinePlus

    ... signs of infestation. Does malathion kill head lice eggs? Yes. The malathion lotion (Ovide*) available by prescription in the United States can kill some lice eggs. Back To Top *Use of trade names is ...

  1. Lice Aren't So Nice

    MedlinePlus

    ... to buy a special medicated shampoo, cream, or lotion that kills lice. An adult will need to ... to remove the nits. The shampoo, cream, or lotion usually kills the lice right away. The itching ...

  2. A New Clade of African Body and Head Lice Infected by Bartonella quintana and Yersinia pestis-Democratic Republic of the Congo.

    PubMed

    Drali, Rezak; Shako, Jean-Christophe; Davoust, Bernard; Diatta, Georges; Raoult, Didier

    2015-11-01

    The human body louse is known as a vector for the transmission of three serious diseases-specifically, epidemic typhus, trench fever, and relapsing fever caused by Rickettsia prowazekii, Bartonella quintana, and Borrelia recurrentis, respectively-that have killed millions of people. It is also suspected in the transmission of a fourth pathogen, Yersinia pestis, which is the etiologic agent of plague. To date, human lice belonging to the genus Pediculus have been classified into three mitochondrial clades: A, B, and C. Here, we describe a fourth mitochondrial clade, Clade D, comprising head and body lice. Clade D may be a vector of B. quintana and Y. pestis, which is prevalent in a highly plague-endemic area near the Rethy Health District, Orientale Province, Democratic Republic of the Congo. PMID:26392158

  3. Microbial symbiosis and the control of vector-borne pathogens in tsetse flies, human lice, and triatomine bugs

    PubMed Central

    Sassera, Davide; Epis, Sara; Pajoro, Massimo; Bandi, Claudio

    2013-01-01

    Symbiosis is a widespread biological phenomenon, and is particularly common in arthropods. Bloodsucking insects are among the organisms that rely on beneficial bacterial symbionts to complement their unbalanced diet. This review is focused on describing symbiosis, and possible strategies for the symbiont-based control of insects and insect-borne diseases, in three bloodsucking insects of medical importance: the flies of the genus Glossina, the lice of the genus Pediculus, and triatomine bugs of the subfamily Triatominae. Glossina flies are vector of Trypanosoma brucei, the causative agent of sleeping sickness and other pathologies. They are also associated with two distinct bacterial symbionts, the primary symbiont Wigglesworthia spp., and the secondary, culturable symbiont Sodalis glossinidius. The primary symbiont of human lice, Riesia pediculicola, has been shown to be fundamental for the host, due to its capacity to synthesize B-group vitamins. An antisymbiotic approach, with antibiotic treatment targeted on the lice symbionts, could represent an alternative strategy to control these ectoparasites. In the case of triatominae bugs, the genetic modification of their symbiotic Rhodococcus bacteria, for production of anti-Trypanosoma molecules, is an example of paratransgenesis, i.e. the use of symbiotic microorganism engineered in order to reduce the vector competence of the insect host. PMID:24188239

  4. Odorant receptor-based discovery of natural repellents of human lice.

    PubMed

    Pelletier, Julien; Xu, Pingxi; Yoon, Kyong S; Clark, John M; Leal, Walter S

    2015-11-01

    The body louse, Pediculus humanus humanus, is an obligate blood-feeding ectoparasite and an important insect vector that mediates the transmission of diseases to humans. The analysis of the body louse genome revealed a drastic reduction of the chemosensory gene repertoires when compared to other insects, suggesting specific olfactory adaptations to host specialization and permanent parasitic lifestyle. Here, we present for the first time functional evidence for the role of odorant receptors (ORs) in this insect, with the objective to gain insight into the chemical ecology of this vector. We identified seven putative full-length ORs, in addition to the odorant receptor co-receptor (Orco), and expressed four of them in the Xenopus laevis oocytes system. When screened with a panel of ecologically-relevant odorants, PhumOR2 responded to a narrow set of compounds. At the behavior level, both head and body lice were repelled by the physiologically-active chemicals. This study presents the first evidence of the OR pathway being functional in lice and identifies PhumOR2 as a sensitive receptor of natural repellents that could be used to develop novel efficient molecules to control these insects. PMID:26494014

  5. Head louse control by suffocation due to blocking their oxygen uptake.

    PubMed

    Al-Quraishy, Saleh; Abdel-Ghaffar, Fathy; Mehlhorn, Heinz

    2015-08-01

    The present study shows that head lice (Pediculus humanus capitis) are killed by suffocation when submersed into the anti-louse shampoo Licener®, which contains a mild shampoo component and an extract of neem seeds after their oil components had been pressed off. It is shown that the inner tracheal system becomes completely filled by the very fluid product. Within 3-10 min, oxygen uptake is prohibited and death of all thus treated lice stages occurred. PMID:25990060

  6. Black Dot Tinea Capitis in an Immunosuppressed Man

    PubMed Central

    Mendese, Gary W.; Loo, Daniel S.

    2013-01-01

    Tinea capitis is a common superficial fungal infection of the scalp primarily afflicting young children. In adults, this infection may have an atypical presentation that may lead to a delay in diagnosis. The authors present a case report of black dot tinea capitis in an immunosuppressed Asian man with psoriasis and provide a review of the literature. PMID:23710273

  7. Detection of a knockdown resistance mutation associated with permethrin resistance in the body louse Pediculus humanus corporis by use of melting curve analysis genotyping.

    PubMed

    Drali, Rezak; Benkouiten, Samir; Badiaga, Sékéné; Bitam, Idir; Rolain, Jean Marc; Brouqui, Philippe

    2012-07-01

    Louse-borne diseases are prevalent in the homeless, and body louse eradication has thus far been unsuccessful in this population. We aim to develop a rapid and robust genotyping method usable in large field-based clinical studies to monitor permethrin resistance in the human body louse Pediculus humanus corporis. We assessed a melting curve analysis genotyping method based on real-time PCR using hybridization probes to detect the M815I-T917I-L920F knockdown resistance (kdr) mutation in the paraorthologous voltage-sensitive sodium channel (VSSC) α subunit gene, which is associated with permethrin resistance. The 908-bp DNA fragment of the VSSC gene, encoding the α subunit of the sodium channel and encompassing the three mutation sites, was PCR sequenced from 65 lice collected from a homeless population. We noted a high prevalence of the 3 indicated mutations in the body lice collected from homeless people (100% for the M815I and L920F mutations and 56.73% for the T917I mutation). These results were confirmed by melting curve analysis genotyping, which had a calculated sensitivity of 100% for the M815I and T917I mutations and of 98% for the L920F mutation. The specificity was 100% for M815I and L920F and 96% for T917I. Melting curve analysis genotyping is a fast, sensitive, and specific tool that is fully compatible with the analysis of a large number of samples in epidemiological surveys, allowing the simultaneous genotyping of 96 samples in just over an hour (75 min). Thus, it is perfectly suited for the epidemiological monitoring of permethrin resistance in human body lice in large-scale clinical studies. PMID:22573588

  8. Borrelia recurrentis in Head Lice, Ethiopia

    PubMed Central

    Boutellis, Amina; Mediannikov, Oleg; Bilcha, Kassahun Desalegn; Ali, Jemal; Campelo, Dayana; Barker, Stephen C.

    2013-01-01

    Since the 1800s, the only known vector of Borrelia recurrentis has been the body louse. In 2011, we found B. recurrentis DNA in 23% of head lice from patients with louse-borne relapsing fever in Ethiopia. Whether head lice can transmit these bacteria from one person to another remains to be determined. PMID:23648147

  9. Identification of repellent odorants to the body louse, Pediculus humanus corporis, in clove essential oil.

    PubMed

    Iwamatsu, Takuma; Miyamoto, Daisuke; Mitsuno, Hidefumi; Yoshioka, Yoshiaki; Fujii, Takeshi; Sakurai, Takeshi; Ishikawa, Yukio; Kanzaki, Ryohei

    2016-04-01

    The control of body lice is an important issue for human health and welfare because lice act as vectors of disease such as typhus, relapsing fever, and trench fever. Body lice exhibit avoidance behavior to some essential oils, including clove essential oil. Therefore, odorants containing clove essential oil components may potentially be useful in the development of repellents to body lice. However, such odorants that induce avoidance behavior in body lice have not yet been identified from clove essential oil. Here, we established an analysis method to evaluate the avoidance behavior of body lice to specific odorants. The behavioral analysis of the body lice in response to clove essential oil and its constituents revealed that eugenol, a major component of clove essential oil, has strong repellent effect on body lice, whereas the other components failed to induce obvious avoidance behavior. A comparison of the repellent effects of eugenol with those of other structurally related odorants revealed possible moieties that are important for the avoidance effects to body lice. The repellent effect of eugenol to body lice was enhanced by combining it with the other major component of clove essential oil, β-caryophyllene. We conclude that a synthetic blend of eugenol and β-caryophyllene is the most effective repellent to body lice. This finding will be valuable as the potential use of eugenol as body lice repellent. PMID:26864790

  10. Head Lice to Dead Lice: Safe Solutions for Frantic Families. A New Treatment Program To Address Persistent Head Lice Infestations. [Videotape].

    ERIC Educational Resources Information Center

    Sawyer Mac Productions, Weston, MA.

    Head lice affect over 10 million Americans each year. Noting that head lice are becoming resistant to conventional pediculicide (insecticide) treatments, this video combines live action and animation to education parents, children, and health professionals about the use of olive oil for successfully preventing and getting rid of head lice. The…

  11. The Lice-Buster Book: What To Do When Your Child Comes Home with Head Lice!

    ERIC Educational Resources Information Center

    Copeland, Lennie

    Noting that every year, 10 to 12 million children contract head lice, this book aims to demystify and provide information about the problem of head lice infestation of children. The first chapter gives statistical details about the problem and its effects on health. Chapter 2 provides factual information concerning the features, life-cycle,…

  12. Insights on virulence from the complete genome of Staphylococcus capitis

    PubMed Central

    Cameron, David R.; Jiang, Jhih-Hang; Hassan, Karl A.; Elbourne, Liam D. H.; Tuck, Kellie L.; Paulsen, Ian T.; Peleg, Anton Y.

    2015-01-01

    Staphylococcus capitis is an opportunistic pathogen of the coagulase negative staphylococci (CoNS). Functional genomic studies of S. capitis have thus far been limited by a lack of available complete genome sequences. Here, we determined the closed S. capitis genome and methylome using Single Molecule Real Time (SMRT) sequencing. The strain, AYP1020, harbors a single circular chromosome of 2.44 Mb encoding 2304 predicted proteins, which is the smallest of all complete staphylococcal genomes sequenced to date. AYP1020 harbors two large mobile genetic elements; a plasmid designated pAYP1020 (59.6 Kb) and a prophage, ΦAYP1020 (48.5 Kb). Methylome analysis identified significant adenine methylation across the genome involving two distinct methylation motifs (1972 putative 6-methyladenine (m6A) residues identified). Putative adenine methyltransferases were also identified. Comparative analysis of AYP1020 and the closely related CoNS, S. epidermidis RP62a, revealed a host of virulence factors that likely contribute to S. capitis pathogenicity, most notably genes important for biofilm formation and a suite of phenol soluble modulins (PSMs); the expression/production of these factors were corroborated by functional assays. The complete S. capitis genome will aid future studies on the evolution and pathogenesis of the coagulase negative staphylococci. PMID:26441910

  13. Management of tinea capitis in childhood

    PubMed Central

    Bennassar, Antoni; Grimalt, Ramon

    2010-01-01

    Tinea capitis (TC) is a common dermatophyte infection affecting primarily prepubertal children. The causative pathogens belong to only two genera: Trichophyton and Microsporum. Although there is a great local variation in the epidemiology of TC worldwide, T. tonsurans is currently the most common cause of TC with M. canis second. Even though there is an emerging number of anthropophilic scalp infections, M. canis remains the predominant causative organism in many countries of the Mediterranean basin, the most important dermatophyte carriers being stray cats and dogs as well as pet puppies, kittens and rabbits. TC always requires systemic treatment because topical antifungal agents do not penetrate down to the deepest part of the hair follicle. Since the late 1950s, griseofulvin has been the gold standard for systemic therapy of TC. It is active against dermatophytes and has a long-term safety profile. The main disadvantage of griseofulvin is the long duration of treatment required which may lead to reduced compliance. The newer oral antifungal agents including terbinafine, itraconazole, ketokonazole, and fluconazole appear to have efficacy rates and potential adverse effects similar to those of griseofulvin in children with TC caused by Trichophyton species, while requiring a much shorter duration of treatment. They may, however, be more expensive. PMID:21437064

  14. 21 CFR 880.5960 - Lice removal kit.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Lice removal kit. 880.5960 Section 880.5960 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL... § 880.5960 Lice removal kit. (a) Identification. The lice removal kit is a comb or comb-like...

  15. Compromising on School for Students with Head Lice

    ERIC Educational Resources Information Center

    Education Digest: Essential Readings Condensed for Quick Review, 2004

    2004-01-01

    Pediculosis, or head lice infestation, has been a public health nuisance for thousands of years. Since most affected children are under 12 years of age, head lice is an elementary school issue. The question then becomes how schools should handle cases of head lice. Some organizations advocate immediately sending children home from school, while…

  16. Head Lice - Multiple Languages: MedlinePlus

    MedlinePlus

    ... French (français) Hindi (हिन्दी) Korean (한국어) Portuguese (português) Russian (Русский) Somali (af Soomaali) Spanish (español) Tagalog ( ... 한국어 (Korean) Bilingual PDF Health Information Translations Portuguese (português) Head Lice Piolho - português (Portuguese) Bilingual PDF Health ...

  17. Head Lice - Multiple Languages: MedlinePlus

    MedlinePlus

    ... List of All Topics All Head Lice - Multiple Languages To use the sharing features on this page, please enable JavaScript. Arabic (العربية) Bosnian (Bosanski) Chinese - Simplified (简体中文) Chinese - Traditional ( ...

  18. Perifolliculitis capitis abscedens et suffodiens successfully controlled with topical isotretinoin.

    PubMed

    Karpouzis, Anthony; Giatromanolaki, Alexandra; Sivridis, Efthymios; Kouskoukis, Constantin

    2003-01-01

    Perifolliculitis capitis abscedens et suffodiens (or dissecting folliculitis of the scalp or dissecting cellulitis of the scalp or dissecting perifolliculitis of the scalp) is a rare entity and constitutes the equivalent over the scalp, of hidradenitis suppurativa and acne conglobata. Etiologic factors are unknown. Diagnosis is proven histologically. Management is very difficult and consists in systemic administration or intralesional injection of several drugs or in surgical manipulations. An 18 year-old white patient with cystic infiltrations, alopecia plaques, pustules and other inflammatory elements (clinicohistological features consistent with dissecting folliculitis of the scalp), is presented. Isotretinoin topical application assured successful control of the disease and averted the evolution of the clinical aspect to scarring alopecia and nodule formation. Topical isotretinoin exercises a curative, inhibitory and antiproliferative action, in perifolliculitis capitis abscedens et suffodiens. PMID:12695138

  19. Tinea capitis in Kwa-Zulu Natal, South Africa.

    PubMed

    Morar, Nilesh; Dlova, Ncoza C; Gupta, Aditya K; Aboobaker, Jamila

    2004-01-01

    Tinea capitis is the most common dermatophyte infection in children. The hair involvement can be classified as endothrix, ectothrix, or favus, and the clinical appearance is variable. The goal of this study was to determine the demography, etiology, and clinical patterns of tinea capitis in South Africa. A prospective, cross-sectional study was conducted over a 1-year period. All cases were classified clinically and subject to Wood light examination, microscopy, and culture. One hundred patients were studied. The male:female ratio was 1.4:1. The mean age was 4.6 years (range 1-11 years). Trichophyton violaceum was isolated in 90% of positive cultures. Wood light was positive in one patient with Microsporum gypseum. The most common clinical variety was the "black dot" type, seen in 50% of patients. Twenty percent of the children presented with more than one clinical type simultaneously. We concluded that the most common cause of tinea capitis in South Africa is T. violaceum. The presentation is variable. PMID:15283786

  20. [Chewing lice (Mallophaga) on birds in the Central Ciscaucasia].

    PubMed

    Liakhov, O M; Kotti, B K

    2010-01-01

    Mallophaga parasitizing wild and domestic birds in the Central Ciscaucasia were studied; 8805 chewing lice specimens were collected and identified. At present, 102 species of Mallophaga are known from this territory, including 15 species recorded in the Central Ciscaucasia for the first time. Most of the chewing lice species in the region under study are parasites of Passeriformes. Species diversity of chewing lice connected with each of other 12 bird orders is several times lesser. The exchange of chewing lice between some species of hosts, particularly between domestic and wild birds, seems possible. PMID:21309151

  1. [Insecticide resistance in lice collected from homeless people in Moscow].

    PubMed

    Lopatina, Iu V; Eremina, O Iu

    2011-01-01

    Permethrin and malathion resistance in body and head lice collected from homeless people in Moscow was investigated in March 2009 to March 2010. Most micropopulations were found to have permethrin-resistant individuals. Their proportion varied from 8.7 to 100%. Cross resistance of body lice to 5 insecticides (the pyrethroids permethrin, d-phenothrin, cypermethrin, deltamethrin, and the organic chlorine compound DDT) was revealed in one case. The lice remained susceptible to organic phosphorus insecticides (fenthion, malathion). The data on permethrin resistance in the lice, obtained by the standard method (immersion of the insects into an insecticide solution), correlated with those yielded by the modified WHO method. PMID:22308710

  2. SdrX, a serine-aspartate repeat protein expressed by Staphylococcus capitis with collagen VI binding activity.

    PubMed

    Liu, Yule; Ames, Brenda; Gorovits, Elena; Prater, Bradley D; Syribeys, Peter; Vernachio, John H; Patti, Joseph M

    2004-11-01

    Staphylococcus capitis (S. capitis) has been implicated in a large proportion of coagulase-negative staphylococcal infections in very-low-birth-weight infants. To identify potential therapeutic targets, the S. capitis genome was probed for the presence of genes encoding microbial surface components recognizing adhesive matrix molecules (MSCRAMM). By using Southern blot analysis, an S. capitis gene, designated sdrX, that contained sequence motifs consistent with the Sdr family of MSCRAMM proteins was identified. By using monospecific antisera in Western blot and flow cytometry, SdrX was demonstrated to be expressed on the surface of S. capitis. Human collagen type VI was found to bind both the recombinant A domain of SdrX and viable S. capitis expressing SdrX. SdrX is the first collagen-binding Sdr protein described and is the first MSCRAMM protein identified in S. capitis. PMID:15501749

  3. An unusual presentation: trichomycosis (trichobacteriosis) capitis in an infant.

    PubMed

    Takcı, Zennure; Karadağ, Ayşe Serap

    2014-01-01

    Trichomycosis (trichobacteriosis) is an asymptomatic superficial bacterial colonization of the hair shaft that is clinically characterized by pale yellowish, reddish or blackish sticky, cylindrical concretions surrounding the hair shaft in the axillary or pubic region. As far as we know, the first and only case of trichomycosis capitis was reported in a 8-year-old boy in 2011. We encountered no cases of trichomycosis in infancy in the literature. The current case displays an atypical presentation of trichobacteriosis involving head hair in a 10-month-old male infant. PMID:26388604

  4. [Management of lice infestations, recommendations for 2012].

    PubMed

    Maillard, Alexia; Trellu, Laurence Toutous; Eicher, Nicole; Michaud, Mélanie; Laffitte, Emmanuel

    2012-04-01

    Pediculosis is the most frequent and contagious ectoparasitic infestation in human, particularly in children from 3 to 8 years of age. Epidemics are observed from time to time, in schools or in adults in prisons. Even though benign, these infections remain unpleasant and can have an important psyco-social impact. Since a few years, caregivers have to face increasing problems while treating lice: appearance of insecticide resistances, lindane's withdrawal from the market and the marketing of new products which are not always well evaluated. This article offers first recalls about pediculoses and then a sum up of the different available treatments with an evidence based management strategy. PMID:22545493

  5. Pediculosis capitis is a growing neglected infestation due to migration in southeast Turkey.

    PubMed

    Eroglu, Fadime; Basaran, Ümit; Kürklü, Cennet Gizem; Yüceer, Mervenur; Yalcıntürk, Rabia Gül; Tanrıverdi, Mustafa; Daglı, Eda Icbay; Koltas, Ismail Soner

    2016-06-01

    Demographic, socio-economical, and environmental changes affecting prevalence of Pediculosis capitis. The aim of this study was to investigate the prevalence of P. capitis and external factors affecting the distribution of P. capitis. A total of 6004 primary-school students between 5 and 11 years were screened for P. capitis at 28 different primary-schools in Gaziantep, located in southeastern of Turkey, during different two education terms (First education term is in September 2013 to May 2014, second education term is in September 2014 and May 2015). The prevalence of P. capitis was found to be positive 1.5 % (90/6004) and 6.9 % (415/6004) in first education term and in second education term, respectively. In this study shown that the rate of P. capitis's prevalence was increased 5.4 % in Gaziantep. P. capitis is a neglected infestation and it has re-emerged in Gaziantep, located in the southeastern of Turkey. Health staff member must improve health education programs in primary-school students especially girl students. PMID:27038249

  6. Human lice show photopositive behaviour to white light.

    PubMed

    Mougabure-Cueto, Gastón; Picollo, María Inés; Lazzari, Claudio R

    2011-10-01

    We studied the behavioural response of body lice and head lice to white light. We also evaluated the influence of starvation and the presence of other individuals on this response. Experiments were performed in a rectangular arena, half of which was illuminated and the other half kept in the dark. Two experiments were performed: in the first, a single louse was released into the arena for 60 min and the percentage of time spent in the illuminated half was recorded; in the second experiment, a group of lice was released and the number of insects in the illuminated half was recorded. The results showed that the average number of lice and time spent in the illuminated side of the arena was statistically higher than for the controls. Starvation did not influence the reaction of lice, but the number of insects in the illuminated area did increase with the size of the group. This study shows that human lice are photopositive towards white light and that this behaviour is not affected by the nutritional state of the insects. Moreover, it is enhanced by the presence of other lice. PMID:21806991

  7. Salmon lice – impact on wild salmonids and salmon aquaculture

    PubMed Central

    Torrissen, O; Jones, S; Asche, F; Guttormsen, A; Skilbrei, O T; Nilsen, F; Horsberg, T E; Jackson, D

    2013-01-01

    Salmon lice, Lepeophtheirus salmonis, are naturally occurring parasites of salmon in sea water. Intensive salmon farming provides better conditions for parasite growth and transmission compared with natural conditions, creating problems for both the salmon farming industry and, under certain conditions, wild salmonids. Salmon lice originating from farms negatively impact wild stocks of salmonids, although the extent of the impact is a matter of debate. Estimates from Ireland and Norway indicate an odds ratio of 1.1:1-1.2:1 for sea lice treated Atlantic salmon smolt to survive sea migration compared to untreated smolts. This is considered to have a moderate population regulatory effect. The development of resistance against drugs most commonly used to treat salmon lice is a serious concern for both wild and farmed fish. Several large initiatives have been taken to encourage the development of new strategies, such as vaccines and novel drugs, for the treatment or removal of salmon lice from farmed fish. The newly sequenced salmon louse genome will be an important tool in this work. The use of cleaner fish has emerged as a robust method for controlling salmon lice, and aquaculture production of wrasse is important towards this aim. Salmon lice have large economic consequences for the salmon industry, both as direct costs for the prevention and treatment, but also indirectly through negative public opinion. PMID:23311858

  8. Advancements in the treatment of head lice in pediatrics.

    PubMed

    Eisenhower, Christine; Farrington, Elizabeth Anne

    2012-01-01

    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. PMID:23099312

  9. Lice update: new solutions to an old problem.

    PubMed

    Wadowski, Lisa; Balasuriya, Lily; Price, Harper N; O'Haver, Judith

    2015-01-01

    An estimated 6 to 12 million children are affected by lice annually in the United States.(1) Knowledge of the various treatment options for this diagnosis is essential. This paper aims to provide an overview of the myriad therapeutic options available for lice infestations in children. U.S. Food and Drug Administration-approved drugs, off-label drug therapies, over-the counter-products, and herbal remedies are all discussed in detail. Clinicians may use this information to teach patients and families about the latest available care for the eradication of head lice in pediatric patients. PMID:25889137

  10. Human pediculosis: a critical health problem and what about nursing policy?

    PubMed

    El-Bahnasawy, Mamdouh M; Abdel, Fadil Eman Ebrahim; Morsy, Tosson A

    2012-12-01

    Lice infestation on the human body (also known as pediculosis) is very common. Cases number in the hundreds of millions worldwide. Three distinct presentations of lice infection exist and each is caused by a unique parasite. Head lice (Pediculus humanus capitis) is by far and away the most common infestation and favors no particular socioeconomic group. A genetically close "cousin," Pediculus humanus corporis, is responsible for body lice and is more commonly associated with poverty, overcrowding, and poor hygiene. Pubic lice (crabs) are caused by Pthirus pubis and is transmitted by intimate and/or sexual contact. No doubt, human lice infestation is an increasing problem worldwide, Apart from being an irritating and a shaming human ecto-parasite, they transmit serious infectious diseases; epidemic or classical typhus, epidemic relapsing fever as well as Trench fever. Eradication of lice infestation prevents transmission of infectious diseases. People who live and work in close proximity to louse-infested individuals may secondarily acquire lice even if they regularly wash their clothes and have good hygiene. Thus, all louse-infested persons and workers in close contact with such persons should periodically inspected and use long-acting safe insecticides. Human lice can be treated with agents such as DDT, malathion, and lindane, but reports of resistance to one or more of them have recently appeared. Pyrethroid permethrin when applied as a dust or spray to clothing or bedding is highly effective against lice and is the delousing agent of choice. Fabric treated with permethrin retains toxicity to lice even after 20 washings, thereby offering significant long-term passive protection against epidemic typhus. Itching may continue even after all lice are destroyed. This happens because of a lingering allergic reactionto their bites. Over-the-counter cortisone (corticosteroid) creams or calamine lotion may help. PMID:23469630

  11. Malathion for head lice and scabies: treatment and safety considerations.

    PubMed

    Idriss, Shereene; Levitt, Jacob

    2009-08-01

    Malathion is an under-recognized and under-utilized therapy for head lice and scabies largely due to misperceptions about its safety profile. Specifically, its pure form as it exists in pharmaceutical preparations is non-toxic to humans in the low doses available. While labeled for ages six and up, recent studies showed no cholinesterase inhibition in head lice patients aged two-to-six treated with malathion. Flammability of malathion in isopropyl alcohol has reportedly resulted in human injury once in over one million prescriptions filled. Recent efficacy studies of malathion in United States (U.S.) head lice demonstrate efficacy rates of 97-98%. In the present era of permethrin and lindane resistance to head lice, malathion is a first-line option. For scabies, it is a reasonable alternative to permethrin 5% cream, especially when treatment of the scalp or hairy areas is desired. PMID:19663108

  12. Why is it crucial to test anti-lice repellents?

    PubMed

    Semmler, Margit; Abdel-Ghaffar, Fathy; Al-Quraishy, Saleh; Al-Rasheid, Khaled A S; Mehlhorn, Heinz

    2012-01-01

    It is difficult to stop lice propagation just by treating infested heads, since reinfections are possible just a few hours after a successful elimination of all lice from a child's head by application of an active anti-louse product. Therefore, several products have been developed that claim to have a louse repellent activity; however, definite proofs are scarce. The present study involving two louse repellents (Linicin® Preventive Spray, Picksan® NoLice) and three substances (at 10% dilution) known for their general repellency activity shows that there are much more difficulties to repel lice when compared to other insects or even ticks. Thus, it must be feared that several repellents on the market might have used a problematical test system and thus might not be as effective as they claim. PMID:21674296

  13. Head Lice No Cause for Panic, Expert Says

    MedlinePlus

    ... Sheehan, a pediatric emergency medicine specialist at the Ann & Robert H. Lurie Children's Hospital of Chicago. Children ... detection and treatment of head lice infestations. SOURCE: Ann & Robert H. Lurie Children's Hospital of Chicago, news ...

  14. Head lice. Dimeticone is the pediculicide of choice.

    PubMed

    2014-07-01

    Infestation of the scalp by head lice, or pediculosis, is a common, unpleasant but harmless parasitosis. For patients with pediculosis, which topical treatment eradicates the parasites effectively while causing the least harm? We reviewed the available evidence using the standard Prescrire methodology. Lice can be eradicated by shaving the head or combing the hair several times a day for several weeks with a fine-toothed lice comb, although combing is only completely effective in about 50% of cases. Pyrethroids (permethrin, phenothrin and bioallethrin), often combined with piperonyl butoxide, are insecticides that are neurotoxic to lice. The lice eradication rates achieved in trials of these agents are highly variable, ranging from 13% to 75% depending on the country, probably due to the development of resistance. In five randomised trials, the organophosphorus insecticide malathion was more effective than permethrin or phenothrin, achieving eradication rates of 80% to 98%. Topical application of the insecticides ivermectin or spinosad was effective in 75% to 85% of patients in randomised trials. Insecticides have mainly local adverse effects: pruritus and irritation of the scalp. Cases of malathion poisoning have been reported following topical application or ingestion. The long-term toxicity of insecticides is unclear; it therefore appears preferable to minimise their use. Agents that kill lice through physical mechanisms have few known adverse effects. It seems unlikely that lice will develop resistance to them. Dimeticone, a silicone compound, is not absorbed through the skin and provokes very few adverse effects. It is one of the better evaluated agents: in three randomised trials, 70% to 97% of patients were lice-free after two weeks. Other agents with a physical action on lice have been evaluated, each in one randomised trial including a few dozen patients. One of these, 1,2-octanediol, applied in an alcoholic solution, seemed to eradicate lice effectively

  15. Prevention and treatment of head lice in children.

    PubMed

    Mumcuoglu, K Y

    1999-01-01

    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

  16. [Current approaches to overcoming permethrin resistance in lice].

    PubMed

    Lopatina, Iu V

    2013-01-01

    The paper gives information on pediculosis morbidity worldwide. It summarizes the data available in the literature on the resistance of head and clothes lice to pyrethroids and on the mechanisms of this resistance. The formation of head and clothes louse populations resistant to pyrethroids is shown to be a global problem. New groups of chemical substances that are alternatives to pyrethroids and the mechanisms of their action on lice are considered. PMID:24003525

  17. [Micromorphology of the malpighian tubules in the louse Pediculus humanus corporis (Anoplura)].

    PubMed

    Chaĭka, S Iu

    1985-01-01

    The ultrastructure of the Malpighian tubes in human louse Pediculus humanus corporis has been studied. The cells of the Malpighian tubules have the uniform structure: the apical surface is covered with microvilli, the basal plasmatic membrana forms relatively small invaginations. The microvilli are most developed in cells of the proximal department of the Malpighian tubules. Microvilli of the apical surface of the cells do not contain mitochondria which are localized mainly in supranuclear part of the cell. Cells are lined with a homogenous basal membrane. PMID:3986247

  18. Evaluation of two methods for quantifying passeriform lice

    PubMed Central

    Koop, Jennifer A. H.; Clayton, Dale H.

    2013-01-01

    Two methods commonly used to quantify ectoparasites on live birds are visual examination and dust-ruffling. Visual examination provides an estimate of ectoparasite abundance based on an observer’s timed inspection of various body regions on a bird. Dust-ruffling involves application of insecticidal powder to feathers that are then ruffled to dislodge ectoparasites onto a collection surface where they can then be counted. Despite the common use of these methods in the field, the proportion of actual ectoparasites they account for has only been tested with Rock Pigeons (Columba livia), a relatively large-bodied species (238–302 g) with dense plumage. We tested the accuracy of the two methods using European Starlings (Sturnus vulgaris; ~75 g). We first quantified the number of lice (Brueelia nebulosa) on starlings using visual examination, followed immediately by dust-ruffling. Birds were then euthanized and the proportion of lice accounted for by each method was compared to the total number of lice on each bird as determined with a body-washing method. Visual examination and dust-ruffling each accounted for a relatively small proportion of total lice (14% and 16%, respectively), but both were still significant predictors of abundance. The number of lice observed by visual examination accounted for 68% of the variation in total abundance. Similarly, the number of lice recovered by dust-ruffling accounted for 72% of the variation in total abundance. Our results show that both methods can be used to reliably quantify the abundance of lice on European Starlings and other similar-sized passerines. PMID:24039328

  19. Walk or ride? Phoretic behaviour of amblyceran and ischnoceran lice.

    PubMed

    Bartlow, Andrew W; Villa, Scott M; Thompson, Michael W; Bush, Sarah E

    2016-04-01

    Phoresy is a behaviour where one organism hitches a ride on another more mobile organism. This is a common dispersal mechanism amongst relatively immobile species that specialise on patchy resources. Parasites specialise on patchily distributed resources: their hosts. Although host individuals are isolated in space and time, parasites must transmit between hosts or they will die with their hosts. Lice are permanent obligate ectoparasites that complete their entire life cycle on their host. They typically transmit when hosts come into direct contact; however, lice are also capable of transmitting phoretically. Yet, phoresy is rare amongst some groups of lice. Fundamental morphological differences have traditionally been used to explain the phoretic differences amongst different suborders of lice; however, these hypotheses do not fully explain observed patterns. We propose that a more fundamental natural history trait may better explain variation in phoresy. Species able to disperse under their own power should be less likely to engage in phoresy than more immobile species. Here we experimentally tested the relationship between independent louse mobility and phoresy using a system with four species of lice (Phthiraptera: Ischnocera and Amblycera) that all parasitize a single host species, the Rock Pigeon (Columba livia). We quantified the relative ability of all four species of lice to move independently off the host, and we quantified their ability to attach to, and remain attached to, hippoboscid flies (Pseudolynchia canariensis). Our results show that the most mobile louse species is the least phoretic, and the most phoretic species is quite immobile off the host. Our findings were consistent with the hypothesis that phoretic dispersal should be rare amongst species of lice that are capable of independent dispersal; however other factors such as interspecific competition may also play a role. PMID:26896575

  20. Prevalence of Tinea Capitis among School Children in Nok Community of Kaduna State, Nigeria.

    PubMed

    Dogo, Josephine; Afegbua, Seniyat Larai; Dung, Edward Christopher

    2016-01-01

    In recent years, the prevalence of tinea capitis, an infection of the scalp by dermatophytes, has increased in children worldwide. This cross-sectional study was carried out to determine the prevalence and risk factor of tinea capitis among school children in Nok community of Kaduna State, Nigeria. A total of 100 children were screened and 45% were diagnosed to have tinea capitis after fungal culture and microscopy. The prevalence of tinea capitis among girls was higher (51.4%) than that among boys (41.5%) but not significantly different (p = 0.402). The prevalence with respect to age was lower for the age group 5-10 years (42.6%) than that of 11-15 years (50%) but was not significantly different (p = 0.524). Trichophyton rubrum (28.8%) and Microsporum canis (22.7%) were the most prevalent dermatophytes isolated and the least were Trichophyton verrucosum (4.5%) and Trichophyton tonsurans (4.5%). There were 73.3% single infection while 26.7% had 2-4 dermatophytes of the genera Microsporum and Trichophyton. The predisposing factors with statistically significant association with tinea capitis were number of children in the family (p = 0.02) and sharing of the same bed (p = 0.002). This indicates the high tendencies of spread of tinea capitis through human-to-human mode of transmission and possible animal contact. Community health education on the cause, mode of transmission, prevention, and prompt treatment of tinea capitis is recommended. PMID:27471603

  1. Prevalence of Tinea Capitis among School Children in Nok Community of Kaduna State, Nigeria

    PubMed Central

    Dogo, Josephine; Dung, Edward Christopher

    2016-01-01

    In recent years, the prevalence of tinea capitis, an infection of the scalp by dermatophytes, has increased in children worldwide. This cross-sectional study was carried out to determine the prevalence and risk factor of tinea capitis among school children in Nok community of Kaduna State, Nigeria. A total of 100 children were screened and 45% were diagnosed to have tinea capitis after fungal culture and microscopy. The prevalence of tinea capitis among girls was higher (51.4%) than that among boys (41.5%) but not significantly different (p = 0.402). The prevalence with respect to age was lower for the age group 5–10 years (42.6%) than that of 11–15 years (50%) but was not significantly different (p = 0.524). Trichophyton rubrum (28.8%) and Microsporum canis (22.7%) were the most prevalent dermatophytes isolated and the least were Trichophyton verrucosum (4.5%) and Trichophyton tonsurans (4.5%). There were 73.3% single infection while 26.7% had 2–4 dermatophytes of the genera Microsporum and Trichophyton. The predisposing factors with statistically significant association with tinea capitis were number of children in the family (p = 0.02) and sharing of the same bed (p = 0.002). This indicates the high tendencies of spread of tinea capitis through human-to-human mode of transmission and possible animal contact. Community health education on the cause, mode of transmission, prevention, and prompt treatment of tinea capitis is recommended. PMID:27471603

  2. Common Hair Problems

    MedlinePlus

    ... lice (pediculosis capitis), and fungal infection of scalp ringworm (tinea capitis). Itching and excessive flaking of the scalp ... sites of shaving, skin friction, or rubbing from… Ringworm, Scalp (Tinea Capitis) Scalp ringworm (tinea capitis) is ...

  3. Amazonian head lice-specific genotypes are putatively pre-Columbian.

    PubMed

    Boutellis, Amina; Veracx, Aurélie; Abrahão, Jônatas; Raoult, Didier

    2013-06-01

    Head and body lice are strict obligate human ectoparasites with three mitochondrial phylotypes (A, B, and C). Using molecular methods for genotyping lice (Cytochrome b and multi-spacer typing), and comparing our results with all the sequences of human lice that were genotyped previously, we assessed the presence of a specific American genotype that most likely predates the Columbian era in head lice collected from Amazonia. PMID:23610158

  4. Akirins in sea lice: first steps towards a deeper understanding.

    PubMed

    Carpio, Yamila; García, Claudia; Pons, Tirso; Haussmann, Denise; Rodríguez-Ramos, Tania; Basabe, Liliana; Acosta, Jannel; Estrada, Mario Pablo

    2013-10-01

    Sea lice (Copepoda, Caligidae) are the most widely distributed marine pathogens in the salmon industry. Vaccination could be an environmentally friendly alternative for sea lice control; however, research on the development of such vaccines is still at an early stage of development. Recent results have suggested that subolesin/akirin/my32 are good candidate antigens for the control of arthropod infestations, including sea lice, but background knowledge about these genes in crustaceans is limited. Herein, we characterize the my32 gene/protein from two important sea lice species, Caligus rogercresseyi and Lepeophtheirus salmonis, based on cDNA sequence isolation, phylogenetic relationships, three dimensional structure prediction and expression analysis. The results show that these genes/proteins have the main characteristics of akirins from invertebrates. In addition, immunization with purified recombinant my32 from L. salmonis elicited a specific antibody response in mice and fish. These results provide an improvement to our current knowledge about my32 proteins and their potential use as vaccine candidates against sea lice in fish. PMID:23850998

  5. Different trichoscopic features of tinea capitis and alopecia areata in pediatric patients.

    PubMed

    El-Taweel, Abd-Elaziz; El-Esawy, Fatma; Abdel-Salam, Osama

    2014-01-01

    Background. Diagnosis of patchy hair loss in pediatric patients is often a matter of considerable debate among dermatologists. Trichoscopy is a rapid and noninvasive tool to detect more details of patchy hair loss. Like clinical dermatology, trichoscopy works parallel to the skin surface and perpendicular to the histological plane; like the histopathology, it thus allows the viewing of structures not discovered by the naked eye. Objective. Aiming to compare the different trichoscopic features of tinea capitis and alopecia areata in pediatric patients. Patients and Methods. This study included 40 patients, 20 patients with tinea capitis and 20 patients with alopecia areata. They were exposed toclinical examination, laboratory investigations (10% KOH and fungal culture), and trichoscope examination. Results. Our obtained results reported that, in tinea capitis patients, comma shaped hairs, corkscrew hairs, and zigzag shaped hairs are the diagnostic trichoscopic features of tinea capitis. While in alopecia areata patients, the most trichoscopic specific features were yellow dots, exclamation mark, and short vellus hairs. Conclusion. Trichoscopy can be used as a noninvasive tool for rapid diagnosis of tinea capitis and alopecia areata in pediatric patients. PMID:25024698

  6. Spinosad for the treatment of head lice infestations.

    PubMed

    Villegas, S C

    2012-09-01

    Head lice infestations continue to be an issue in today's society, with an increase in economic cost and resistance. Spinosad 0.9% topical suspension was recently introduced in the U.S. market as a novel agent with both pediculicidal and ovicidal activity, approved in children 4 years of age and older for the treatment of head lice infestations. In clinical trials, it has demonstrated effectiveness against head lice with permethrin resistance. In two clinical trials comparing spinosad to permethrin, efficacy was observed in the spinosad-treated groups at 84.6% and 86.7%, respectively, when compared to the permethrin-treated groups (respective values of 44.9% and 42.9%; P < 0.001). Overall, spinosad was well tolerated in clinical trials. PMID:23032800

  7. Fish Lice (Argulus japonicus) in Goldfish (Carassius auratus)

    PubMed Central

    Wafer, Lemnique N; Whitney, Jesse C; Jensen, V Behrana

    2015-01-01

    Fish lice (Argulus spp; family Argulidae) are branchiuran crustaceans that parasitize both marine and freshwater fishes. Argulus spp can be a major threat to fish health, because heavy infestations can cause significant morbidity and mortality. In addition, fish lice are known to be the vehicle for other fish diseases. During rounds at our facility, Argulus japonicus was collected from the caudal and anal fins of 3 goldfish (Carassius auratus).These goldfish were asymptomatic, and no additional cases were noted after manual removal of the lice. As soon as any Argulus organisms are identified, management and treatment are recommended because infections can escalate rapidly. Currently, there are no FDA-approved drugs for the control and treatment of this parasite, but several chemicals including organophosphates and diflubenzuron have been used with success. The screening and quarantine of incoming fish is the best way to avoid a facility-wide Argulus infestation. PMID:25926394

  8. Fish Lice (Argulus japonicus) in Goldfish (Carassius auratus).

    PubMed

    Wafer, Lemnique N; Whitney, Jesse C; Jensen, V Behrana

    2015-04-01

    Fish lice (Argulus spp; family Argulidae) are branchiuran crustaceans that parasitize both marine and freshwater fishes. Argulus spp can be a major threat to fish health, because heavy infestations can cause significant morbidity and mortality. In addition, fish lice are known to be the vehicle for other fish diseases. During rounds at our facility, Argulus japonicus was collected from the caudal and anal fins of 3 goldfish (Carassius auratus). These goldfish were asymptomatic, and no additional cases were noted after manual removal of the lice. As soon as any Argulus organisms are identified, management and treatment are recommended because infections can escalate rapidly. Currently, there are no FDA-approved drugs for the control and treatment of this parasite, but several chemicals including organophosphates and diflubenzuron have been used with success. The screening and quarantine of incoming fish is the best way to avoid a facility-wide Argulus infestation. PMID:25926394

  9. Keep Your Wits Not Your Nits: A Rational Approach to Head Lice from the National Pediculosis Association. Second Edition.

    ERIC Educational Resources Information Center

    Altschuler, Deborah Z.; And Others

    This booklet was intended to teach parents about head lice, which are small, wingless, crawling insects that feed on human blood. The booklet briefly discusses: (1) physical characteristics of lice; (2) ways of becoming infested with head lice, such as sharing combs; (3) nits, which are the eggs of lice; (4) the difference between nits and hair…

  10. Evolutionary history of mammalian sucking lice (Phthiraptera: Anoplura)

    PubMed Central

    2010-01-01

    Background Sucking lice (Phthiraptera: Anoplura) are obligate, permanent ectoparasites of eutherian mammals, parasitizing members of 12 of the 29 recognized mammalian orders and approximately 20% of all mammalian species. These host specific, blood-sucking insects are morphologically adapted for life on mammals: they are wingless, dorso-ventrally flattened, possess tibio-tarsal claws for clinging to host hair, and have piercing mouthparts for feeding. Although there are more than 540 described species of Anoplura and despite the potential economical and medical implications of sucking louse infestations, this study represents the first attempt to examine higher-level anopluran relationships using molecular data. In this study, we use molecular data to reconstruct the evolutionary history of 65 sucking louse taxa with phylogenetic analyses and compare the results to findings based on morphological data. We also estimate divergence times among anopluran taxa and compare our results to host (mammal) relationships. Results This study represents the first phylogenetic hypothesis of sucking louse relationships using molecular data and we find significant conflict between phylogenies constructed using molecular and morphological data. We also find that multiple families and genera of sucking lice are not monophyletic and that extensive taxonomic revision will be necessary for this group. Based on our divergence dating analyses, sucking lice diversified in the late Cretaceous, approximately 77 Ma, and soon after the Cretaceous-Paleogene boundary (ca. 65 Ma) these lice proliferated rapidly to parasitize multiple mammalian orders and families. Conclusions The diversification time of sucking lice approximately 77 Ma is in agreement with mammalian evolutionary history: all modern mammal orders are hypothesized to have diverged by 75 Ma thus providing suitable habitat for the colonization and radiation of sucking lice. Despite the concordant timing of diversification events

  11. Identification and comparative analysis of G protein-coupled receptors in Pediculus humanus humanus.

    PubMed

    Li, Chengjun; Song, Xiaowen; Chen, Xuhong; Liu, Xing; Sang, Ming; Wu, Wei; Yun, Xiaopei; Hu, Xingxing; Li, Bin

    2014-07-01

    The body louse has the smallest genome size among the known genome-sequenced insects. Here, 81 GPCRs were identified in Pediculus humanus humanus, 56, 14, 6 and 5 GPCRs for family-A, -B, -C and -D, respectively. These GPCRs constitute the comparable repertoire of GPCRs with other insects. Moreover, it contains a more complete set of neuropeptide and protein hormone receptors not even than Acyrthosiphon pisum but also Drosophila melanogaster, for example, Sulfakinin, Corazonin, Trissin and PTHRL only presented in P. h. humanus but lost either in A. pisum or D. melanogaster. However, it has less duplication among the sub-families. Meanwhile, ACP, AVPL, HE6 receptors and Boss were also absent from P. h. humanus. These results indicated that the repertoire of GPCRs in P. h. humanus were not affected by its smallest genome size, and further suggested that P. h. humanus has a relatively original and concise GPCR regulation system. PMID:24952173

  12. Prophylactic Ketoconazole Shampoo for Tinea Capitis in a High-Risk Pediatric Population

    PubMed Central

    Bookstaver, P. Brandon; Watson, Holly J.; Winters, Shauna D.; Carlson, Adrian L.; Schulz, Richard M.

    2011-01-01

    OBJECTIVES Although topical agents for the treatment of tinea capitis decrease viable fungal elements and reduce shedding, their use as a prophylactic agent has not been investigated. This study evaluated the effectiveness of a prophylactic ketoconazole shampoo (Nizoral 2%) protocol to reduce the number of clinically evident tinea capitis infections in a high-risk African American, urban population. METHODS We conducted a retrospective analysis of a ketoconazole prophylaxis protocol that was implemented at an urban pediatric clinic for medically fragile children. Patients at high risk for tinea capitis received twice-weekly ketoconazole shampoo. The primary outcome of the study was a reduction in the number of documented tinea capitis infections between the 12-month preprotocol and 12-month postprotocol periods. A secondary outcome included the evaluation of predisposing risk factors for acquiring tinea infections. RESULTS Ninety-seven patients, with a mean age of 8.06 years, were included. Most patients (78%) were African American. There were a total of 13 tinea capitis infections during the 12-month preprotocol period. During the 12-month postprotocol period, 41 infections were documented: 37 (90.2%) in the prophylaxis group and 4 (9.8%) in the nonprophylaxis group. The average numbers of per-patient infections in the postprotocol period were 0.79 and 0.08 in the prophylaxis and nonprophylaxis groups, respectively. Initiation of prophylaxis did not reduce tinea capitis infections (p=NS). Previous history of infection and a high level of care were significant predictors of infections (p<0.05). CONCLUSIONS Improved hygiene, adherence to prescribed treatment regimens, and prevention of recurrent environmental exposure to surviving fomites should be stressed in high-risk patients and supersede the need for an antifungal (ketoconazole shampoo) prophylaxis protocol. PMID:22479162

  13. Efficacy of spray formulations containing binary mixtures of clove and eucalyptus oils against susceptible and pyrethroid/ malathion-resistant head lice (Anoplura: Pediculidae).

    PubMed

    Choi, Han-Young; Yang, Young-Cheol; Lee, Si Hyeock; Clark, J Marshall; Ahn, Young-Joon

    2010-05-01

    The control efficacy of clove, Eugenia caryophyllata, and eucalyptus, Eucalyptus globulus, essential oils and 15 formulations containing these essential oils alone (8, 12, and 15% sprays) and their binary mixtures (7:3, 5:5, and 3:7 by weight) against adult females of insecticide-susceptible KR-HL and dual malathion- and permethrin-resistant BR-HL strains of head louse, Pediculus humanus capitis (De Geer), was examined by using contact plus fumigant and human hair wig (placed over the head of mannequin) mortality bioassays. In contact plus fumigant mortality bioassay, essential oils from eucalyptus (0.225 mg/cm2) and clove (1.149 mg/cm2) were less effective than either d-phenothrin (0.0029 mg/cm2) or pyrethrum (0.0025 mg/cm2) based on 6-h median lethal concentration values. However, the efficacies of eucalyptus and clove oils were almost identical against females fromn both strains, despite high levels of resistance of the BR-HL females to d-phenothrin (resistance ratio, 667) and pyrethrum (resistance ratio, 754). In human hair wig mortality bioassay, eucalyptus oil spray treatment gave better control efficacy than either spray treatment with clove oil alone or their binary mixtures. Thus, eucalyptus applied as 8% sprays (15 or 20 ml) appears to provide effective protection against pediculosis even to insecticide-resistant head louse populations. Once the safety issues resolved, covering the treated hair and scalp with bath shower cap or hat would ensure the fumigant action of the essential oil. PMID:20496586

  14. Socioeconomic status, family background and other key factors influence the management of head lice in Norway.

    PubMed

    Rukke, Bjørn Arne; Soleng, Arnulf; Lindstedt, Heidi Heggen; Ottesen, Preben; Birkemoe, Tone

    2014-05-01

    How head lice infestations are managed by households is an important but generally neglected issue in head lice research. In the present study, we investigate actions taken against head lice by Norwegian households in association with socioeconomic status, family background, school-related variables and other key factors. Repeat questionnaires distributed to caretakers of the same elementary school children during a 2-year period enabled us to study both previous head lice management and any changes in this management through time. Households from 12 schools spanning the main socioeconomic variation found in Norway participated in the study. All students with active head lice infestation were treated in the four investigated periods. Most caretakers used a thorough head lice checking technique and informed others of own infestation. Checking frequency was low as most children were inspected less than monthly. The best determinant of increased checking frequency and thoroughness was personal experience with head lice. The increased awareness, however, seemed to be somewhat short-lived, as there was a decrease in checking frequency and thoroughness within 1 year after infestation. Personal experience with head lice also increased general knowledge related to the parasite. Parents born in developing countries checked their children for head lice more frequently, although less thoroughly, informed fewer contacts when infested, used pediculicides preventively more often and knew less about head lice than parents born in developed countries. Households with highly educated mothers had a lower checking frequency, but their knowledge and willingness to inform others was high. Single parents were more concerned about economic costs and kept children home from school longer while infested than other parents. As head lice management varied among socioeconomic groups and with parental background, differentiated advice should be considered in the control of head lice. The

  15. A Policy Change Strategy for Head Lice Management

    ERIC Educational Resources Information Center

    Andresen, Kathleen; McCarthy, Ann Marie

    2009-01-01

    The purpose of this project was to formulate an effective change strategy for head lice management in a group of five separate school districts within one county. Despite a desire to use evidence to support their practice, school nurses often encounter educational system barriers that prevent independent management of health conditions. The use of…

  16. Estimating costs of sea lice control strategy in Norway.

    PubMed

    Liu, Yajie; Bjelland, Hans Vanhauwaer

    2014-12-01

    This paper explores the costs of sea lice control strategies associated with salmon aquaculture at a farm level in Norway. Diseases can cause reduction in growth, low feed efficiency and market prices, increasing mortality rates, and expenditures on prevention and treatment measures. Aquaculture farms suffer the most direct and immediate economic losses from diseases. The goal of a control strategy is to minimize the total disease costs, including biological losses, and treatment costs while to maximize overall profit. Prevention and control strategies are required to eliminate or minimize the disease, while cost-effective disease control strategies at the fish farm level are designed to reduce the losses, and to enhance productivity and profitability. Thus, the goal can be achieved by integrating models of fish growth, sea lice dynamics and economic factors. A production function is first constructed to incorporate the effects of sea lice on production at a farm level, followed by a detailed cost analysis of several prevention and treatment strategies associated with sea lice in Norway. The results reveal that treatments are costly and treatment costs are very sensitive to treatment types used and timing of the treatment conducted. Applying treatment at an early growth stage is more economical than at a later stage. PMID:25443395

  17. Risk Factors for Human Lice and Bartonellosis among the Homeless, San Francisco, California, USA

    PubMed Central

    Cole-Porse, Charsey; Kjemtrup, Anne; Osikowicz, Lynn; Kosoy, Michael

    2014-01-01

    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. PMID:25280380

  18. An experience from an outbreak of tinea capitis gladiatorum due to Trichophyton tonsurans.

    PubMed

    Ergin, S; Ergin, C; Erdoğan, B S; Kaleli, I; Evliyaoğlu, D

    2006-03-01

    'Tinea corporis gladiatorum' describes a dermatophytosis transmitted mainly from close skin contact among wrestlers. Although tinea corporis is well recognized, no data are available for tinea capitis infections in wrestlers. After finding tinea capitis infection in a student wrestler, we aimed to search for possible ringworm infections among wrestlers in a wrestling boarding-school. Of the 32 wrestlers, 29, aged 12-18 years, were affected, of whom 22 had scalp involvement. Trichophyton tonsurans was isolated from 20 of the patients, and T. mentagrophytes from the remaining two. Isolated strains of dermatophytes were susceptible to terbinafine and itraconazole. The patients with tinea capitis received oral terbinafine for 4 weeks, and patients with more than two lesions but without scalp involvement received oral terbinafine for 2 weeks. Overall clinical and mycological cure rate was 72.4% and 70%, respectively, at assessment at week 6. The asymptomatic dermatophyte carrier rate was negative 1 year after control of the epidemic. Terbinafine seems to be an alternative drug for the treatment of tinea capitis caused by T. tonsurans; however, control of an outbreak may be very difficult and effective preventive measures should be considered. PMID:16487093

  19. Inflammatory tinea capitis (kerion) mimicking dissecting cellulitis. Occurrence in two adolescents.

    PubMed

    Sperling, L C

    1991-03-01

    Tinea capitis is unusual in postpubertal individuals and is frequently misdiagnosed. In cases of inflammatory disease, prompt initiation of therapy is essential to prevent scarring and permanent hair loss. Two examples are presented to illustrate principles of evaluation and treatment. PMID:2037403

  20. Aspergillus niger - a possible new etiopathogenic agent in Tinea capitis? Presentation of two cases.

    PubMed

    Chokoeva, Anastasiya Atanasova; Zisova, Liliya; Chorleva, Kristina; Tchernev, Georgi

    2016-01-01

    Tinea capitis is generally considered as the most frequent fungal infection in childhood, as it accounts for approximately 92% of all mycosis in children. The epidemiology of this disease varies widely ranging from antropophillic, zoophilic, and geophillic dermatophytes, as the main causative agent in different geographic areas, depending on several additional factors. Nowadays, the etiology is considered to vary with age, as well with gender, and general health condition. The former reported extraordinary Tinea capitis case reports have been replaced by original articles and researches dealing with progressively changing patterns in etiology and clinical manifestation of the disease. This fact is indicative that under the umbrella of the well-known disease there are facts still hidden for future revelations. Herein, we present two rare cases of Tinea capitis in children, which totally differ from the recently established pattern, in their clinical presentation, as well as in the etiological aspect, as we discuss this potential new etiological pattern of the disease, focusing on our retrospective and clinical observation. Collected data suggest that pathogenic molds should be considered as a potential source of infection in some geographic regions, which require total rationalization of the former therapeutic conception, regarding the molds' higher antimitotic resistance compared to dermatophytes. Molds-induced Tinea capitis should be also considered in clinically resistant and atypical cases, with further investigations of the antifungal susceptibility of the newest pathogens in the frame of the old disease. Further investigations are still needed to confirm or reject this proposal. PMID:26963152

  1. [Comparative activity of different groups of insecticides against permethrin-resistant lice (anoplura: pediculidae)].

    PubMed

    Lopatina, Iu V; Eremina, O Iu

    2013-01-01

    The activity of insecticides (CK50, CK95 ) from different chemical classes against permethrin-resistant body and head lice was investigated. Having developed resistance to pyrethroids (permethrin, d-phenothrin, cypermethrin, and deltamethrin), the lice remain susceptible to organophosphorus compounds, phenylpyrazoles, neonicotinoids, and avermectins. The susceptibility of lice to the insecticides having a mechanism of action that is different from that of pyrethroids does not depend on the level of their resistance to permethrin. PMID:23805484

  2. Substantial Variation in the Extent of Mitochondrial Genome Fragmentation among Blood-Sucking Lice of Mammals

    PubMed Central

    Jiang, Haowei; Barker, Stephen C.; Shao, Renfu

    2013-01-01

    Blood-sucking lice of humans have extensively fragmented mitochondrial (mt) genomes. Human head louse and body louse have their 37 mt genes on 20 minichromosomes. In human pubic louse, the 34 mt genes known are on 14 minichromosomes. To understand the process of mt genome fragmentation in the blood-sucking lice of mammals, we sequenced the mt genomes of the domestic pig louse, Haematopinus suis, and the wild pig louse, H. apri, which diverged from human lice approximately 65 Ma. The 37 mt genes of the pig lice are on nine circular minichromosomes; each minichromosome is 3–4 kb in size. The pig lice have four genes per minichromosome on average, in contrast to two genes per minichromosome in the human lice. One minichromosome of the pig lice has eight genes and is the most gene-rich minichromosome found in the sucking lice. Our results indicate substantial variation in the rate and extent of mt genome fragmentation among different lineages of the sucking lice. PMID:23781098

  3. Taxonomy of lice and their endosymbiotic bacteria in the post-genomic era.

    PubMed

    Boyd, B M; Reed, D L

    2012-04-01

    Recent studies of molecular and genomic data from the parasitic lice of birds and mammals, as well as their mutualistic endosymbiotic bacteria, are changing the phylogenetic relationships and taxonomy of these organisms. Phylogenetic studies of lice suggest that vertebrate parasitism arose multiple times from free-living book and bark lice. Molecular clocks show that the major families of lice arose in the late Mesozoic and radiated in the early Cenozoic, following the radiation of mammals and birds. The recent release of the human louse genome has provided new opportunities for research. The genome is being used to find new genetic markers for phylogenetics and population genetics, to understand the complex evolutionary relationships of mitochondrial genes, and to study genome evolution. Genomes are informing us not only about lice, but also about their obligate endosymbiotic bacteria. In contrast to lice and their hosts, lice and their endosymbionts do not share common evolutionary histories, suggesting that endosymbionts are either replaced over time or that there are multiple independent origins of symbiosis in lice. Molecular phylogenetics and whole genome sequencing have recently provided the first insights into the phylogenetic placement and metabolic characteristics of these distantly related bacteria. Comparative genomics between distantly related louse symbionts can provide insights into conserved metabolic functions and can help to explain how distantly related species are fulfilling their role as mutualistic symbionts. In lice and their endosymbionts, molecular data and genome sequencing are driving our understanding of evolutionary relationships and classification, and will for the foreseeable future. PMID:22429457

  4. Severe pediculosis capitus: a case of "crusted lice" with autoeczematization.

    PubMed

    Connor, Cody J; Selby, John C; Wanat, Karolyn A

    2016-01-01

    Pediculosis humanus capitus infestations are common and classically present with intense pruritus of the scalp. Although many treatment options are available, lice are becoming more resistant to conventional therapies and severe clinical presentations are bound to become more prevalent. We present a case of treatment-resistant pediculosis capitus resulting in diffuse autoeczematization of the torso and extremities and severe crusting and scaling of the scalp, which we called "crusted lice." This eruption differs from the well-described id reaction known as "pediculid" and represents a more dramatic manifestation of rampant infestation. This paper provides an up-to-date review of treatment options available for pediculosis humanus capitus, including newer medications like the ones that eventually led to resolution of our patient's extreme infestation. PMID:27136626

  5. Drug resistance in sea lice: a threat to salmonid aquaculture.

    PubMed

    Aaen, Stian Mørch; Helgesen, Kari Olli; Bakke, Marit Jørgensen; Kaur, Kiranpreet; Horsberg, Tor Einar

    2015-02-01

    Sea lice are copepod ectoparasites with vast reproductive potential and affect a wide variety of fish species. The number of parasites causing morbidity is proportional to fish size. Natural low host density restricts massive parasite dispersal. However, expanded salmon farming has shifted the conditions in favor of the parasite. Salmon farms are often situated near wild salmonid migrating routes, with smolts being particularly vulnerable to sea lice infestation. In order to protect both farmed and wild salmonids passing or residing in the proximity of the farms, several measures are taken. Medicinal treatment of farmed fish has been the most predictable and efficacious, leading to extensive use of the available compounds. This has resulted in drug-resistant parasites occurring on farmed and possibly wild salmonids. PMID:25639521

  6. Head lice treatments: Searching for the path of least resistance.

    PubMed

    Heymann, Warren R

    2009-08-01

    Based on the dialogue "Head lice" between Drs Kimberly D. Morel and Stephen Stone. Dialogues in Dermatology, a monthly audio program from the American Academy of Dermatology, contains discussions between dermatologists on timely topics. Commentaries from Dialogues Editor-in-Chief Warren R. Heymann, MD, are provided after each discussion as a topic summary and are provided here as a special service to readers of the Journal of the American Academy of Dermatology. PMID:19615542

  7. Chewing lice (Phthiraptera) from wild birds in southern Portugal.

    PubMed

    Tomás, André; Palma, Ricardo L; Rebelo, Maria Teresa; da Fonseca, Isabel Pereira

    2016-06-01

    This study was carried out to determine chewing louse species of wild birds in the Ria Formosa Natural Park, located in southern Portugal. In addition, the hypothesis that bird age, avian migration and social behaviour have an impact on the louse prevalence was tested. Between September and December of 2013, 122 birds (belonging to 10 orders, 19 families, 31 genera and 35 species) captured in scientific ringing sessions and admitted to the Wildlife Rehabilitation and Investigation Centre of Ria Formosa were examined for lice. Twenty-six (21.3%) birds were found to be infested with at least one chewing louse species. The chewing lice identified include 18 species. Colonial birds (34.9%) and migratory birds (29.5%) had statistically significant higher prevalence than territorial birds (6.8%) and resident birds (13.1%), respectively. This paper records 17 louse species for the first time in southern Portugal: Laemobothrion maximum, Laemobothrion vulturis, Actornithophilus piceus lari, Actornithophilus umbrinus, Austromenopon lutescens, Colpocephalum heterosoma, Colpocephalum turbinatum, Eidmanniella pustulosa, Nosopon casteli, Pectinopygus bassani, Pseudomenopon pilosum, Trinoton femoratum, Trinoton querquedulae, Craspedorrhynchus platystomus, Degeeriella fulva, Falcolipeurus quadripustulatus, Lunaceps schismatus. Also a nymph of the genus Strigiphilus was collected from a Eurasian eagle-owl. These findings contribute to the knowledge of avian chewing lice from important birds areas in Portugal. PMID:26899014

  8. Ecomorphology of parasite attachment: experiments with feather lice.

    PubMed

    Bush, Sarah E; Sohn, Edward; Clayton, Dale H

    2006-02-01

    The host specificity of some parasites can be reinforced by morphological specialization for attachment to mobile hosts. For example, ectoparasites with adaptations for attaching to hosts of a particular size might not be able to remain attached to larger or smaller hosts. This hypothesis is suggested by the positive correlation documented between the body sizes of many parasites and their hosts. We adopted an ecomorphological approach to test the attachment hypothesis. We tested the ability of host-specific feather lice (Phthiraptera: Ischnocera) to attach to 6 novel species of pigeons and doves that vary in size by nearly 2 orders of magnitude. Surprisingly, Rock Pigeon lice (Columbicola columbae) remained attached equally well to all 6 novel host species. We tested the relative importance of 3 factors that could facilitate louse attachment: whole-body insertion, tarsal claw use, and mandible use. Insertion, per se, was not necessary for attachment. However, insertion on coarse feathers of large hosts allowed lice to access feather barbules with their mandibles. Mandible use was a key component of attachment regardless of feather size. Attachment constraints do not appear to reinforce host specificity in this system. PMID:16629310

  9. Survival away from sheep and alternative methods of transmission of sheep lice (Bovicola ovis).

    PubMed

    Crawford, S; James, P J; Maddocks, S

    2001-01-01

    Transmission of sheep lice is thought to occur mainly by sheep to sheep contact although the possibility of other sources of infestation is often suggested. This study investigated the period of survival of Bovicola ovis after removal from sheep under varying conditions and assessed the likelihood of new infestations arising from contaminated facilities, wool caught on fences and shearers' footwear. In laboratory studies with lice held away from sheep at 4, 20, 25 and 36.5 degrees C, adults and nymphs survived longest at 25 degrees C (LT90 of 11.7 and 24.1 days for adults and large nymphs, respectively). Nymphs survived longer than adults and lice provided with raw wool survived longer than lice provided with wool that had been degreased. Nymphal lice survived for up to 29 days on unscoured wool at 36.5 degrees C, but the LT50 was less than 9 days in most experiments. In shearing sheds in winter and early spring lice survived for up to 14 and 16 days, respectively. These periods of survival are considerably longer than previously indicated for B. ovis. Most lice dropped out of wool staples attached to a fence within 1 h and only two of a total of 225 lice were still present after 24 h, suggesting that sheep are unlikely to become infested from wool caught on fences. Adult and nymphal lice readily transferred to shearers' moccasins and survived there for up to 10 days, indicating that transmission of lice on the footwear of shearers or other sheep handlers may be a cause of new infestations. Microwaving each moccasin for 5 min killed all lice and may provide a simple method of reducing the likelihood of transmission of B. ovis between properties. PMID:11113551

  10. Patterns of attachment of the myodural bridge by the rectus capitis posterior minor muscle.

    PubMed

    Yuan, Xiao-Ying; Yu, Sheng-Bo; Li, Yun-Fei; Chi, Yan-Yan; Zheng, Nan; Gao, Hai-Bin; Luan, Bing-Yi; Zhang, Zhao-Xi; Sui, Hong-Jin

    2016-03-01

    The myodural bridge was first described by Hack in 1995 and was thought to be related to chronic cervicogenic headaches. For a long time, few studies revealed the patterns of the myodural bridge considering the rectus capitis posterior minor muscle. In this study, P45 plastination technology and anatomical dissection were performed on head specimens, and four different terminal region types of the rectus capitis posterior minor muscle were observed, including the posterior atlanto-occipital interspace, posterior arch of the atlas and posterior atlanto-axial interspace. We propose that the myodural complex structures in the posterior atlanto-occipital and posterior atlanto-axial interspace have cooperative effects on cerebrospinal fluid and work together. This force might be an important source for the circulation of cerebrospinal fluid. PMID:25859757

  11. Intractable occipital neuralgia caused by an entrapment in the semispinalis capitis.

    PubMed

    Son, Byung-Chul; Kim, Deok-Ryeong; Lee, Sang-Won

    2013-09-01

    Occipital neuralgia is a rare pain syndrome characterized by periodic lancinating pain involving the occipital nerve complex. We present a unique case of entrapment of the greater occipital nerve (GON) within the semispinalis capitis, which was thought to be the cause of occipital neuralgia. A 66-year-old woman with refractory left occipital neuralgia revealed an abnormally low-loop of the left posterior inferior cerebellar artery on the magnetic resonance imaging, suggesting possible vascular compression of the upper cervical roots. During exploration, however, the GON was found to be entrapped at the perforation site of the semispinalis capitis. There was no other compression of the GON or of C1 and C2 dorsal roots in their intracranial course. Postoperatively, the patient experienced almost complete relief of typical neuralgic pain. Although occipital neuralgia has been reported to occur by stretching of the GON by inferior oblique muscle or C1-C2 arthrosis, peripheral compression in the transmuscular course of the GON in the semispinalis capitis as a cause of refractory occipital neuralgia has not been reported and this should be considered when assessing surgical options for refractory occipital neuralgia. PMID:24278663

  12. Head lice predictors and infestation dynamics among primary school children in Norway

    PubMed Central

    Birkemoe, Tone; Lindstedt, Heidi Heggen; Ottesen, Preben; Soleng, Arnulf; Næss, Øyvind; Rukke, Bjørn Arne

    2016-01-01

    Background. Health providers need to know which measures to take and children to prioritize in order to decrease costs associated with head lice infestations. Objective. Our aim was to determine the most important predictors for head lice and identify the major drivers of an infestation outbreak in a low-prevalence area. Methods. The study was based on three datasets of head lice prevalence (retrospective, point prevalence and prospective approach) from primary school children (ages 6–12) at 12 schools in Oslo, Norway. The tested predictors were siblings with lice, individual and household characteristics as well as class and school affiliation. Self-reported monthly incidences (prospective approach) of head lice were used to evaluate infestation dynamics. Results. Infested siblings strongly increased the odds of head lice infestation of school children (odds ratio 36, 26 and 7 in the three datasets) whereas having short hair halved the odds. Household characteristics were of minor importance, and class affiliation proved more important than school affiliation. Having head lice in one school term increased the odds of an infestation in the next, but this effect diminished over time. About 97% of all self-reported infestations were noted in two consecutive months or less. Conclusions. With the exception of hair length, we have found that individual and household characteristics are of minor importance to predict head lice infestations in a low-prevalence country and that unnoticed transmissions in school classes and families are likely to be the major driver upon outbreaks. PMID:26511728

  13. Network centrality and seasonality interact to predict lice load in a social primate

    PubMed Central

    Duboscq, Julie; Romano, Valeria; Sueur, Cédric; MacIntosh, Andrew J.J.

    2016-01-01

    Lice are socially-transmitted ectoparasites. Transmission depends upon their host’s degree of contact with conspecifics. While grooming facilitates ectoparasite transmission via body contact, it also constrains their spread through parasite removal. We investigated relations between parasite burden and sociality in female Japanese macaques following two opposing predictions: i) central females in contact/grooming networks harbour more lice, related to their numerous contacts; ii) central females harbour fewer lice, related to receiving more grooming. We estimated lice load non-invasively using the conspicuous louse egg-picking behaviour performed by macaques during grooming. We tested for covariation in several centrality measures and lice load, controlling for season, female reproductive state and dominance rank. Results show that the interaction between degree centrality (number of partners) and seasonality predicted lice load: females interacting with more partners had fewer lice than those interacting with fewer partners in winter and summer, whereas there was no relationship between lice load and centrality in spring and fall. This is counter to the prediction that increased contact leads to greater louse burden but fits the prediction that social grooming limits louse burden. Interactions between environmental seasonality and both parasite and host biology appeared to mediate the role of social processes in louse burden. PMID:26915589

  14. Molecular typing study of the Microsporum canis strains isolated from an outbreak of tinea capitis in a school.

    PubMed

    Yu, Jin; Wan, Zhe; Chen, Wei; Wang, Wenling; Li, Ruoyu

    2004-01-01

    Tinea capitis is a dermatophyte infection of the scalp that occurs most often in prepubescent children. Tinea capitis may be transmitted by shared use of contaminated hairbrush, by contact with fomites or by direct physical contact with an infected person. Occasionally, outbreak of tinea capitis would happen under some special conditions. Last year, we found an outbreak of tinea capitis in a school due to Microsporum canis. In epidemiological study, we performed the prevalence survey to all of the exposed persons by physical examinations and mycological laboratory tests, including KOH preparation and fungal cultures. We also investigated the environment in the school. In molecular typing study of the M. canis isolated from patients and the environment, random primer amplification polymorphic DNA (RAPD) method, the specific amplification of subrepeat element in the ribosomal DNA nontranscribed spacer (NTS), and the analysis of DNA sequence in the intertranscribed spacer (ITS) of rDNA were performed. The total number of exposed children was seventy-one, among them forty-two were attacked by tinea capitis. The ratio between boy and girl was 13:1. The ages of the patients was ranged from 3.5 years old to 10 years old. Four patients bred cat or dog as pet. Most patients appeared noninflammatory type of tinea capitis and several patients were inflammatory type. Under microscopic examination the invaded hair were all ectothrix. The pathogens isolated from these patients were M. canis. And we also isolated M. canis from the carpet and the pillowcase in the school. The patterns of total strains of M. canis in the RAPD method and PCR amplification of the rDNA NTS region study were identical, and the isolates from patients and the environment contained the same DNA sequences in the ITS region. The outbreak of tinea capitis was caused by M. canis. The M. canis isolated from patients and from the environment were probably the same origin. PMID:15008343

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

    PubMed

    Koch, T; Brown, M; Selim, P; Isam, C

    2001-05-01

    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. PMID:11820546

  16. Repeated adaptive divergence of microhabitat specialization in avian feather lice

    PubMed Central

    2012-01-01

    Background Repeated adaptive radiations are evident when phenotypic divergence occurs within lineages, but this divergence into different forms is convergent when compared across lineages. Classic examples of such repeated adaptive divergence occur in island (for example, Caribbean Anolis lizards) and lake systems (for example, African cichlids). Host-parasite systems in many respects are analogous to island systems, where host species represent isolated islands for parasites whose life cycle is highly tied to that of their hosts. Thus, host-parasite systems might exhibit interesting cases of repeated adaptive divergence as seen in island and lake systems. The feather lice of birds spend their entire life cycle on the body of the host and occupy distinct microhabitats on the host: head, wing, body and generalist. These microhabitat specialists show pronounced morphological differences corresponding to how they escape from host preening. We tested whether these different microhabitat specialists were a case of repeated adaptive divergence by constructing both morphological and molecular phylogenies for a diversity of avian feather lice, including many examples of head, wing, body and generalist forms. Results Morphological and molecular based phylogenies were highly incongruent, which could be explained by rampant convergence in morphology related to microhabitat specialization on the host. In many cases lice from different microhabitat specializations, but from the same group of birds, were sister taxa. Conclusions This pattern indicates a process of repeated adaptive divergence of these parasites within host group, but convergence when comparing parasites across host groups. These results suggest that host-parasite systems might be another case in which repeated adaptive radiations could be relatively common, but potentially overlooked, because morphological convergence can obscure evolutionary relationships. PMID:22717002

  17. Evolution of tinea capitis in the Nanchang area, Southern China: a 50-year survey (1965-2014).

    PubMed

    Zhan, Ping; Geng, Chengfang; Li, Zhihua; Jin, Yun; Jiang, Qing; Tao, Li; Luo, Yunpeng; Xiong, Zhiwei; Wu, Shaoxi; Li, Dongmei; Liu, Weida; de Hoog, G Sybren

    2015-05-01

    Tinea capitis remains a common public health problem worldwide especially in developing areas. Aetiologic agents and clinical pattern vary with geography and history of socioeconomic conditions. Three community surveys and a prospective study were carried out over the past 50 years (1965-2014) in the Qingyunpu District of Nanchang, Southern China. Clinical presentation and spectrum of aetiological agents were monitored to understand the evolution of tinea capitis. In 1965 favus was highly epidemic and Trichophyton schoenleinii presented as the overwhelming aetiological agents of scalp infection in the study area, with a prevalence of 3.41% of the population. During a governmental campaign to eliminate tinea capitis initiated in mid of 1960s, favus was successfully controlled and the prevalence decreased to less than 0.01% in 1977. After that period, clinical presentation and spectrum of fungi changed with social development. Trichophyton schoenleinii was replaced by Trichophyton violaceum and Trichophyton mentagrophytes. Nowadays, the species corresponds with a dominant black dot type of tinea capitis in the Nanchang area. The prevalence of causative agents of tinea capitis is not only related to geography but also to socioeconomic factors. Multiple factors have to be considered for the management for control of this disease. PMID:25756741

  18. Fragmented mitochondrial genomes in two suborders of parasitic lice of eutherian mammals (Anoplura and Rhynchophthirina, Insecta)

    PubMed Central

    Shao, Renfu; Barker, Stephen C; Li, Hu; Song, Simon; Poudel, Shreekanta; Su, Yuan

    2015-01-01

    Parasitic lice (order Phthiraptera) infest birds and mammals. The typical animal mitochondrial (mt) genome organization, which consists of a single chromosome with 37 genes, was found in chewing lice in the suborders Amblycera and Ischnocera. The sucking lice (suborder Anoplura) known, however, have fragmented mt genomes with 9–20 minichromosomes. We sequenced the mt genome of the elephant louse, Haematomyzus elephantis – the first species of chewing lice investigated from the suborder Rhynchophthirina. We identified 33 mt genes in the elephant louse, which were on 10 minichromosomes. Each minichromosome is 3.5–4.2 kb in size and has 2–6 genes. Phylogenetic analyses of mt genome sequences confirm that the elephant louse is more closely related to sucking lice than to the chewing lice in the Amblycera and Ischnocera. Our results indicate that mt genome fragmentation is shared by the suborders Anoplura and Rhynchophthirina. Nine of the 10 mt minichromosomes of the elephant louse differ from those of the sucking lice (Anoplura) known in gene content and gene arrangement, indicating that distinct mt karyotypes have evolved in Anoplura and Rhynchophthirina since they diverged ~92 million years ago. PMID:26617060

  19. Proteomic analysis of epidermal mucus from sea lice-infected Atlantic salmon, Salmo salar L.

    PubMed

    Provan, F; Jensen, L B; Uleberg, K E; Larssen, E; Rajalahti, T; Mullins, J; Obach, A

    2013-03-01

    Health diets that contain immunostimulants and other functional ingredients can strengthen the immune response in Atlantic salmon, Salmo salar, and thereby reduce sea lice, Lepeophtheirus salmonis, infection levels. Such diets can be used to supplement other treatments and will potentially reduce the need for delousing and medication. A sea lice infection trial was conducted on fish with an average weight of 215 g. One control diet and four experimental diets containing functional ingredients were produced. The diets were fed to salmon for 4 weeks before infection with sea lice copepodids. When lice had developed to chalimus III/IV, 88 fish per diet were examined for lice loads. Mucus samples from fish fed the different diets were taken before and after lice infection. Mass spectrometry-based proteomics was used to characterize the protein composition in the epidermal mucus of Atlantic salmon and to identify quantitative alterations in protein expression. Multivariate analysis of the generated data sets was performed to identify protein biomarkers. Putative biomarkers associated with functional feed intake and with sea lice infection have been identified and can form the basis for strategic validation experiments with selected functional feeds. PMID:23305410

  20. Chewing lice (Phthiraptera) species of wild birds in northwestern Turkey with a new host record☆

    PubMed Central

    Girisgin, Ahmet Onur; Dik, Bilal; Girisgin, Oya

    2013-01-01

    The goal of this study was to identify the chewing lice species of migratory and non-migratory wild birds in the province of Bursa, which is located in northwestern Turkey, between August 2009 and November 2012. Sixty-eight birds brought to the animal hospital in need of medical intervention, which belonged to 25 species, 20 genera and 15 families in 10 orders, were examined for ectoparasites. To sample for the presence of chewing lice, an insecticide was pulverised on the feathers of each bird over a white piece of paper, and then all of the lice were collected and placed in tubes containing 70% alcohol. The lice specimens were cleared in 10% KOH for 24 h, mounted in Canada balsam and identified using a light microscope. Forty (58.8%) out of 68 birds examined were infested with at least one species of chewing lice, and a total of 29 lice species were found on the birds. This study represents the first documentation in Turkey of 9 of these lice species and also provides the first worldwide record of Degeeriella nisus on the Common buzzard (Buteo buteo). PMID:24533339

  1. Vertical transmission of feather lice between adult blackbirds Turdus merula and their nestlings: a lousy perspective.

    PubMed

    Brooke, M de L

    2010-12-01

    There is limited information about the natural history of the transmission of feather lice (Phthiraptera) from parent birds to their young. This article therefore examines the transmission of 4 species of feather lice from parent blackbirds to their nestlings in an English population, and addresses questions formulated from the perspective of the lice. The lice that disperse onto the several young in the nest were mostly found on the larger chicks, those with higher survival prospects. The lice dispersing to chicks were overwhelmingly nymphs, which cannot be sexed morphologically, and so the prediction that the adult lice dispersing would be disproportionately female, potential founders of a new population, was only supported for the most numerous species, Brueelia merulensis. There was no evidence that louse dispersal to chicks was density dependent and more likely when the parents were more heavily infested. Finally, I predicted that lice might aggregate on female blackbirds, which undertake more brooding, to increase their chance of transmission to nestlings. For 1 louse species, B. merulensis, prevalence, but not louse intensity, was higher on female than male blackbirds. For 2 other louse species, Philopterus turdi and Menacanthus eurysternus, no differences between male and female blackbirds were detected. PMID:21158613

  2. Rates of genomic divergence in humans, chimpanzees and their lice

    PubMed Central

    Johnson, Kevin P.; Allen, Julie M.; Olds, Brett P.; Mugisha, Lawrence; Reed, David L.; Paige, Ken N.; Pittendrigh, Barry R.

    2014-01-01

    The rate of DNA mutation and divergence is highly variable across the tree of life. However, the reasons underlying this variation are not well understood. Comparing the rates of genetic changes between hosts and parasite lineages that diverged at the same time is one way to begin to understand differences in genetic mutation and substitution rates. Such studies have indicated that the rate of genetic divergence in parasites is often faster than that of their hosts when comparing single genes. However, the variation in this relative rate of molecular evolution across different genes in the genome is unknown. We compared the rate of DNA sequence divergence between humans, chimpanzees and their ectoparasitic lice for 1534 protein-coding genes across their genomes. The rate of DNA substitution in these orthologous genes was on average 14 times faster for lice than for humans and chimpanzees. In addition, these rates were positively correlated across genes. Because this correlation only occurred for substitutions that changed the amino acid, this pattern is probably produced by similar functional constraints across the same genes in humans, chimpanzees and their ectoparasites. PMID:24403325

  3. The rhizome of Reclinomonas americana, Homo sapiens, Pediculus humanus and Saccharomyces cerevisiae mitochondria

    PubMed Central

    2011-01-01

    Background Mitochondria are thought to have evolved from eubacteria-like endosymbionts; however, the origin of the mitochondrion remains a subject of debate. In this study, we investigated the phenomenon of chimerism in mitochondria to shed light on the origin of these organelles by determining which species played a role in their formation. We used the mitochondria of four distinct organisms, Reclinomonas americana, Homo sapiens, Saccharomyces cerevisiae and multichromosome Pediculus humanus, and attempted to identify the origin of each mitochondrial gene. Results Our results suggest that the origin of mitochondrial genes is not limited to the Rickettsiales and that the creation of these genes did not occur in a single event, but through multiple successive events. Some of these events are very old and were followed by events that are more recent and occurred through the addition of elements originating from current species. The points in time that the elements were added and the parental species of each gene in the mitochondrial genome are different to the individual species. These data constitute strong evidence that mitochondria do not have a single common ancestor but likely have numerous ancestors, including proto-Rickettsiales, proto-Rhizobiales and proto-Alphaproteobacteria, as well as current alphaproteobacterial species. The analysis of the multichromosome P. humanus mitochondrion supports this mechanism. Conclusions The most plausible scenario of the origin of the mitochondrion is that ancestors of Rickettsiales and Rhizobiales merged in a proto-eukaryotic cell approximately one billion years ago. The fusion of the Rickettsiales and Rhizobiales cells was followed by gene loss, genomic rearrangements and the addition of alphaproteobacterial elements through ancient and more recent recombination events. Each gene of each of the four studied mitochondria has a different origin, while in some cases, multichromosomes may allow for enhanced gene exchange

  4. Synergistic activity of antibiotics combined with ivermectin to kill body lice.

    PubMed

    Sangaré, Abdoul Karim; Rolain, Jean Marc; Gaudart, Jean; Weber, Pascal; Raoult, Didier

    2016-03-01

    Ivermectin and doxycycline have been found to be independently effective in killing body lice. In this study, 450 body lice were artificially fed on a Parafilm™ membrane with human blood associated with antibiotics (doxycycline, erythromycin, rifampicin and azithromycin) alone and in combination with ivermectin. Fluorescence in situ hybridisation and spectral deconvolution were performed to evaluate bacterial transcriptional activity following antibiotic intake by the lice. In the first series, a lethal effect of antibiotics on lice was observed compared with the control group at 18 days (log-rank test, P≤10(-3)), with a significant difference between groups in the production of nits (P=0.019, Kruskal-Wallis test). A high lethal effect of ivermectin alone (50ng/mL) was observed compared with the control group (log-rank test, P≤10(-3)). Fluorescence of bacteriocytes in lice treated with 20μg/mL doxycycline was lower than in untreated lice (P<0.0001, Kruskal-Wallis test). In the second series with antibiotic-ivermectin combinations, a synergistic lethal effect on treated lice (log-rank test, P<10(-6)) was observed compared with the control group at 18 days, associated with a significant decrease in the production of nits (P≤0.001, Kruskal-Wallis test). Additionally, survival of lice in the combination treatment groups compared with ivermectin alone was significant (log-rank test, P=0.0008). These data demonstrate that the synergistic effect of combinations of antibiotics and ivermectin could be used to achieve complete eradication of lice and to avoid selection of a resistant louse population. PMID:26897755

  5. Chewing lice in Azorean Blackcaps ( Sylvia atricapilla ): a contribution to parasite island syndromes.

    PubMed

    Literák, Ivan; Sychra, Oldřich; Resendes, Roberto; Rodrígues, Pedro

    2015-04-01

    Focusing upon chewing lice (Phthiraptera: Amblycera, Ischnocera) parasitizing blackcaps ( Sylvia atricapilla ) in the Azores (Portugal), we found a lower number of louse species in the Azores compared to mainland Europe. Only chewing lice host specific to blackcaps were found in the Azores. Louse prevalences were much higher in blackcaps from the Azores compared to those of various mainland populations. Chewing lice are permanent parasites of birds, and for such parasites the parasite island syndrome could be characterized by higher parasite prevalence on the islands compared to the mainland. PMID:25279583

  6. The Chewing Lice (Insecta, Phthiraptera) Fauna of the Swainson's Warbler, Limnothlypis swainsonii (Aves, Parulidae).

    PubMed

    Valim, Michel P; Reiley, Bryan M

    2015-09-01

    We examined Swainson's warblers (Limnothlypis swainsonii (Audubon, 1834), Aves: Parulidae) for lice fauna during 2 yr at three study sites in Arkansas, USA. A total of 66 individuals were examined; eight birds (10.6%) were parasitized with 16 lice of two new species belonging to two genera Myrsidea Waterson, 1915 (Amblycera: Menoponidae) and Brueelia Kéler, 1936 (Ischnocera: Philopteridae). Parasitological parameter data are given on the prevalence of lice on Swainson's warblers. Species descriptions and illustrations are provided for Myrsidea bensoni sp. nov. and Brueelia limnothlypiae sp. nov.; including a key for females of the genus Myrsidea that parasitize Parulidae (Passeriformes). PMID:26336250

  7. [Identification of geophilic and zoophilic dermatophytes in siblings with tinea capitis. A pathogenic factor or contamination?].

    PubMed

    Lehmann, S; Ott, H; Barker, M; Heimann, G; Poblete-Gutiérrez, P; Frank, J

    2004-10-01

    Two siblings of African origin presented with multiple scaling patches and alopecia on the scalp four weeks after returning from a vacation in Eritrea. Direct KOH examination revealed fungal elements; Trichophyton mentagrophytes and Trichophyton terrestre were identified in the fungal culture. We discuss the putative pathogenic role of both microorganisms in causing disease. Although infection with Microsporum canis currently accounts for almost fifty percent of all cases of tinea capitis in Germany, other fungi have gained importance due to tourism and increasing migration. PMID:15340708

  8. Casuarinacola, a new genus of jumping plant lice (Hemiptera: Triozidae) from Casuarina (Casuarinaceae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new genus, Casuarinacola comprising four new species, namely C. equisetifoliae, C. acutialata, C. melanomaculata and C. warrigalensis, of jumping plant lice (Hemiptera: Triozidae), specific to the host genus Casuarina sensu stricto (Casuarinaceae) from Australia, are described. They are characteri...

  9. Understanding and Managing Head Lice | NIH MedlinePlus the Magazine

    MedlinePlus

    ... treated at the same time. Over-the-counter lotions and shampoos that contain pyrethrin—a common synthetic ... or numbness. Prescription-strength five-percent permethrin, malathion lotion, or benzyl alcohol lotion may be needed. Lice ...

  10. Studies of Ancient Lice Reveal Unsuspected Past Migrations of Vectors

    PubMed Central

    Drali, Rezak; Mumcuoglu, Kosta Y.; Yesilyurt, Gonca; Raoult, Didier

    2015-01-01

    Lice are among the oldest parasites of humans representing an excellent marker of the evolution and migration of our species over time. Here, we analyzed by real-time polymerase chain reaction (RT-PCR) developed in this study the mitochondrial DNA of seven ancient head louse eggs found on hair remains recovered from two sites in Israel: 1) five nits dating from Chalcolithic period (4,000 bc) were found in the Cave of the Treasure located at Nahal Mishmar, in the Judean Desert and 2) two nits dating from Early Islamic Period (ad 650–810) were found in Nahal Omer in the Arava Valley (between Dead Sea and Red Sea). Our results suggest that these eggs belonged to people originating from west Africa based on identification of the louse mitochondrial sub-clade specific to that region. PMID:26078317

  11. Studies of Ancient Lice Reveal Unsuspected Past Migrations of Vectors.

    PubMed

    Drali, Rezak; Mumcuoglu, Kosta Y; Yesilyurt, Gonca; Raoult, Didier

    2015-09-01

    Lice are among the oldest parasites of humans representing an excellent marker of the evolution and migration of our species over time. Here, we analyzed by real-time polymerase chain reaction (RT-PCR) developed in this study the mitochondrial DNA of seven ancient head louse eggs found on hair remains recovered from two sites in Israel: 1) five nits dating from Chalcolithic period (4,000 bc) were found in the Cave of the Treasure located at Nahal Mishmar, in the Judean Desert and 2) two nits dating from Early Islamic Period (ad 650-810) were found in Nahal Omer in the Arava Valley (between Dead Sea and Red Sea). Our results suggest that these eggs belonged to people originating from west Africa based on identification of the louse mitochondrial sub-clade specific to that region. PMID:26078317

  12. [Pyrethroid resistance in human lice (Anoplura, Pediculidae): toxicological and molecular genetic methods].

    PubMed

    Lopatina, Iu V; Eremina, O Iu; Karan', L S

    2015-01-01

    The paper gives the data obtained in toxicological experiments versus analysis by a real-time polymerase chain reaction assay in permethrin-resistant human lice (VSSC1 gene kdr mutations leading to the amino acid replacements T9171 and L920F have been found). It is shown that the results of toxicological experiments may be indirectly indicative of the genetic composition of a study sample of lice. PMID:25850312

  13. The control of sea lice in Atlantic salmon by selective breeding.

    PubMed

    Gharbi, Karim; Matthews, Louise; Bron, James; Roberts, Ron; Tinch, Alan; Stear, Michael

    2015-09-01

    Sea lice threaten the welfare of farmed Atlantic salmon and the sustainability of fish farming across the world. Chemical treatments are the major method of control but drug resistance means that alternatives are urgently needed. Selective breeding can be a cheap and effective alternative. Here, we combine experimental trials and diagnostics to provide a practical protocol for quantifying resistance to sea lice. We then combined quantitative genetics with epidemiological modelling to make the first prediction of the response to selection, quantified in terms of reduced need for chemical treatments. We infected over 1400 young fish with Lepeophtheirus salmonis, the most important species in the Northern Hemisphere. Mechanisms of resistance were expressed early in infection. Consequently, the number of lice per fish and the ranking of families were very similar at 7 and 17 days post infection, providing a stable window for assessing susceptibility to infection. The heritability of lice numbers within this time window was moderately high at 0.3, confirming that selective breeding is viable. We combined an epidemiological model of sea lice infection and control on a salmon farm with genetic variation in susceptibility among individuals. We simulated 10 generations of selective breeding and examined the frequency of treatments needed to control infection. Our model predicted that substantially fewer chemical treatments are needed to control lice outbreaks in selected populations and chemical treatment could be unnecessary after 10 generations of selection. Selective breeding for sea lice resistance should reduce the impact of sea lice on fish health and thus substantially improve the sustainability of Atlantic salmon production. PMID:26289656

  14. The control of sea lice in Atlantic salmon by selective breeding

    PubMed Central

    Gharbi, Karim; Matthews, Louise; Bron, James; Roberts, Ron; Tinch, Alan; Stear, Michael

    2015-01-01

    Sea lice threaten the welfare of farmed Atlantic salmon and the sustainability of fish farming across the world. Chemical treatments are the major method of control but drug resistance means that alternatives are urgently needed. Selective breeding can be a cheap and effective alternative. Here, we combine experimental trials and diagnostics to provide a practical protocol for quantifying resistance to sea lice. We then combined quantitative genetics with epidemiological modelling to make the first prediction of the response to selection, quantified in terms of reduced need for chemical treatments. We infected over 1400 young fish with Lepeophtheirus salmonis, the most important species in the Northern Hemisphere. Mechanisms of resistance were expressed early in infection. Consequently, the number of lice per fish and the ranking of families were very similar at 7 and 17 days post infection, providing a stable window for assessing susceptibility to infection. The heritability of lice numbers within this time window was moderately high at 0.3, confirming that selective breeding is viable. We combined an epidemiological model of sea lice infection and control on a salmon farm with genetic variation in susceptibility among individuals. We simulated 10 generations of selective breeding and examined the frequency of treatments needed to control infection. Our model predicted that substantially fewer chemical treatments are needed to control lice outbreaks in selected populations and chemical treatment could be unnecessary after 10 generations of selection. Selective breeding for sea lice resistance should reduce the impact of sea lice on fish health and thus substantially improve the sustainability of Atlantic salmon production. PMID:26289656

  15. Perifolliculitis capitis abscedens et suffodiens in a caucasian: diagnostic and therapeutic challenge.

    PubMed

    Mihić, Liborija Lugović; Tomas, Davor; Situm, Mirna; Krolo, Iva; Sebetić, Klaudija; Sjerobabski-Masnec, Ines; Barišić, Freja

    2011-01-01

    Perifolliculitis capitis abscedens et suffodiens or dissecting cellulitis of the scalp is a rare, chronic destructive folliculitis of the scalp, characterized by painful nodules, purulent drainage, sinus tracts, keloid formation and cicatricial alopecia. The cause of the disease is unknown, but it is similar in many features to hidradenitis suppurativa and acne conglobata. In our case report, the patient's dermatologic appearance included one slightly erythematous, infiltrated alopecic area with draining lesions in the right parietal part of the scalp with a few alopecic areas in other parts of the scalp. The identification of the infectious agent, repeated swabs and KOH examination/or fungal cultures and tissue sampling for histopathologic analysis were necessary to confirm the diagnosis of perifolliculitis capitis abscedens et suffodiens. The patient received systemic antibiotics (azithromycin and amoxicillin-clavulanate) and oral antimycotic therapy (fluconazole), followed by a long period of oral isotretinoin with local skin care, which led to resolution and thus inhibited the evolution to scarring and nodular stage of the disease. Thus, such combined approach could be useful for other patients with these dermatologic problems. PMID:21703156

  16. In Vitro and In Vivo Evaluation of Infestation Deterrents Against Lice

    PubMed Central

    Yoon, Kyong Sup; Ketzis, Jennifer K.; Andrewes, Samuel W.; Wu, Christopher S.; Honraet, Kris; Staljanssens, Dorien; Rossel, Bart; Marshall Clark, J.

    2015-01-01

    The human head louse is a cosmopolitan ectoparasite and frequently infests many people, particularly school-age children. Due to widespread pyrethroid resistance and the lack of efficient resistance management, there has been a considerable interest in the protection of uninfested people and prevention of reinfestation by disrupting lice transfer. In this study, two nonclinical model systems (in vitro and in vivo) were used to determine the efficacy of the infestation deterrents, Elimax lotion and Elimax shampoo, against human head lice or poultry chewing lice, respectively. With in vitro assessments, female head lice exhibited significantly higher avoidance responses to hair tufts treated with either of the test formulations, which led to significantly higher ovipositional avoidance when compared with female lice on control hair tufts. Additionally, both formulations were determined to be competent infestation deterrents in a competitive avoidance test in the presence of a known attractant (head louse feces extract). In in vivo assessments using a previously validated poultry model, Elimax shampoo was determined to be an efficacious deterrent against poultry chewing lice within Menopon spp. and Menacanthus spp. PMID:26336209

  17. In Vitro and In Vivo Evaluation of Infestation Deterrents Against Lice.

    PubMed

    Yoon, Kyong Sup; Ketzis, Jennifer K; Andrewes, Samuel W; Wu, Christopher S; Honraet, Kris; Staljanssens, Dorien; Rossel, Bart; Marshall Clark, J

    2015-09-01

    The human head louse is a cosmopolitan ectoparasite and frequently infests many people, particularly school-age children. Due to widespread pyrethroid resistance and the lack of efficient resistance management, there has been a considerable interest in the protection of uninfested people and prevention of reinfestation by disrupting lice transfer. In this study, two nonclinical model systems (in vitro and in vivo) were used to determine the efficacy of the infestation deterrents, Elimax lotion and Elimax shampoo, against human head lice or poultry chewing lice, respectively. With in vitro assessments, female head lice exhibited significantly higher avoidance responses to hair tufts treated with either of the test formulations, which led to significantly higher ovipositional avoidance when compared with female lice on control hair tufts. Additionally, both formulations were determined to be competent infestation deterrents in a competitive avoidance test in the presence of a known attractant (head louse feces extract). In in vivo assessments using a previously validated poultry model, Elimax shampoo was determined to be an efficacious deterrent against poultry chewing lice within Menopon spp. and Menacanthus spp. PMID:26336209

  18. Modelling sea lice dispersion under varying environmental forcing in a Scottish sea loch.

    PubMed

    Amundrud, T L; Murray, A G

    2009-01-01

    The spread of infectious larval sea lice, Lepeophtheirus salmonis (Krøyer, 1838), between wild salmonids and farmed Atlantic salmon, Salmo salar, remains a contentious area of uncertainty. However, as laboratory and field experiments increase our knowledge of sea lice behaviour under environmental forcing, numerical modelling tools can be used to predict the spread of infectious sea louse larvae from a point source. A three-dimensional numerical model has been developed and recently validated within Loch Torridon, a fjordic sea loch on the west coast of Scotland. Output from the numerical model is used to drive a particle tracking model which follows statistical representations of sea lice through the planktonic stages of a louse life cycle. By including maturation and mortality, the models can be used to predict the dispersion and transport of infectious sea lice from a point source and can be used to produce maps of infectivity under varying environmental conditions. Results highlight the importance of the wind-driven circulation for larval lice transport and suggest that local environmental conditions have considerable impact on the probability of sea lice infection spreading between wild and farmed fish populations. PMID:19245629

  19. Can neck exercises enhance the activation of the semispinalis cervicis relative to the splenius capitis at specific spinal levels?

    PubMed

    Schomacher, Jochen; Erlenwein, Joachim; Dieterich, Angela; Petzke, Frank; Falla, Deborah

    2015-10-01

    The deep cervical extensor, semispinalis cervicis, displays changes in behaviour and structure in people with chronic neck pain yet there is limited knowledge on how activation of this muscle can be emphasized during training. Using intramuscular electromyography (EMG), this study investigated the activity of the deep semispinalis cervicis and the superficial splenius capitis muscle at two spinal levels (C2 and C5) in ten healthy volunteers during a series of neck exercises: 1. Traction and compression, 2. Resistance applied in either flexion or extension at the occiput, at the level of the vertebral arch of C1 and of C4, and 3. Maintaining the neck in neutral while inclined on the elbows, with and without resistance at C4. The ratio between semispinalis cervicis and the splenius capitis EMG amplitude was quantified as an indication of whether the exercise could emphasize the activation of the semispinalis cervicis muscle relative to the splenius capitis. Manual resistance applied in extension over the vertebral arch emphasized the activation of the semispinalis cervicis relative to the splenius capitis at the spinal level directly caudal to the site of resistance (ratio: 2.0 ± 1.1 measured at C5 with resistance at C4 and 2.1 ± 1.2 measured at C2 with resistance at C1). This study confirmed the possibility of emphasizing the activation of the semispinalis cervicis relative to the splenius capitis which may be relevant for targeted exercise interventions for this deep extensor muscle. Further studies are required to investigate the clinical efficacy of these exercises for people with neck pain. PMID:25935795

  20. Chewing lice (Phthiraptera) on chickens (Gallus gallus) from small backyard flocks in the eastern part of the Czech Republic.

    PubMed

    Sychra, O; Harmat, P; Literák, I

    2008-04-15

    One hundred and sixty chickens (Gallus gallus) from 31 small, private backyard flocks in the eastern part of the Czech Republic were examined for chewing lice (Phthiraptera: Amblycera, Ischnocera). At least one species of chewing lice was found on every bird examined. Seven species of chewing lice were identified in all; they had the following prevalences and mean intensities: Goniocotes gallinae (100%; 110 lice), Menopon gallinae (88%; 50), Menacanthus stramineus (48%; 17), Lipeurus caponis (35%; 12), Menacanthus cornutus (12%; 9), Cuclotogaster heterographus (1%; 4) and Goniocotes microthorax (1%; 3). Just two birds from a single flock were heavily infested with the ischnoceran species G. gallinae. PMID:18280661

  1. Efficacy and Safety of Dimeticone in the Treatment of Lice Infestation through Prophylaxis of Classmates

    PubMed Central

    FERRARA, Pietro; DEL BUFALO, Francesca; ROMANO, Valerio; TIBERI, Eloisa; BOTTARO, Giorgia; ROMANI, Lorenza; MALAMISURA, Monica; IANNIELLO, Francesca; CENI, Laura; MOTTINI, Giovanni; GATTO, Antonio

    2013-01-01

    Background We conducted a study to evaluate efficacy and safety of dimeticone 4%, a lotion with no conventional insecticide activity, to cure lice infection and to prevent spread of infestation/reinfestation by prophylaxis of classmates. Methods: The study is carried out between April 2008 and June 2008 in Petranova International Institute in Rome. A total of 131 children, aged 3 to 13 years (median age: 7 years) were included in the study. All participants received treatment with dimeticone 4% that was applied both to children with the infestation, to cure it, and to all classmates, to prevent the spreading of the infestation. They have been controlled after 7 and 30 days from the application of dimeticone. Results: At baseline we found a positivity of lice infestation in 23/131 children (17.6%), whereas 108/131 (82.4%) children were free from lice. After 7 days of treatment with dimeticone 4%, 7/23 (30.4%) positive children still had lice infestation, with a cure rate of 69.6% (16/23). At 30 days 26/131 children (19.9%) were infested: 15 children were lice free at baseline whereas 11 had lice at both evaluations; the cure rate amounted to 52.2% (12/23). The reinfestation rate (percentage of positive children that showed negativity at baseline) was 5.3% (7/131) at 7 days and 11.5% (15/131) at 30 days. Conclusion: The lower reinfestation rate showed in our trial suggests that this approach could be effective in reducing spreading of head lice in small communities. More studies are needed to confirm our findings. PMID:24427749

  2. Predicting the effectiveness of depth-based technologies to prevent salmon lice infection using a dispersal model.

    PubMed

    Samsing, Francisca; Johnsen, Ingrid; Stien, Lars Helge; Oppedal, Frode; Albretsen, Jon; Asplin, Lars; Dempster, Tim

    2016-07-01

    Salmon lice is one of the major parasitic problems affecting wild and farmed salmonid species. The planktonic larval stages of these marine parasites can survive for extended periods without a host and are transported long distances by water masses. Salmon lice larvae have limited swimming capacity, but can influence their horizontal transport by vertical positioning. Here, we adapted a coupled biological-physical model to calculate the distribution of farm-produced salmon lice (Lepeophtheirus salmonis) during winter in the southwest coast of Norway. We tested 4 model simulations to see which best represented empirical data from two sources: (1) observed lice infection levels reported by farms; and (2) experimental data from a vertical exposure experiment where fish were forced to swim at different depths with a lice-barrier technology. Model simulations tested were different development time to the infective stage (35 or 50°-days), with or without the presence of temperature-controlled vertical behaviour of lice early planktonic stages (naupliar stages). The best model fit occurred with a 35°-day development time to the infective stage, and temperature-controlled vertical behaviour. We applied this model to predict the effectiveness of depth-based preventive lice-barrier technologies. Both simulated and experimental data revealed that hindering fish from swimming close to the surface efficiently reduced lice infection. Moreover, while our model simulation predicted that this preventive technology is widely applicable, its effectiveness will depend on environmental conditions. Low salinity surface waters reduce the effectiveness of this technology because salmon lice avoid these conditions, and can encounter the fish as they sink deeper in the water column. Correctly parameterized and validated salmon lice dispersal models can predict the impact of preventive approaches to control this parasite and become an essential tool in lice management strategies. PMID

  3. Benign and malignant thyroid neoplasms after childhood irradiation for Tinea capitis. [X-ray

    SciTech Connect

    Ron, E.; Modan, B.

    1980-07-01

    The incidence of all thyroid surgery was studied among 10,842 persons whose thyroid glands had been exposed in childhood to an average dose of 9 rads of x-radiation during treatment for tinea capitis and among 2 matched control groups. A statistically significant increased risk for both benign and malignant neoplasms was found in the exposed group. The excess risk was 8.3 cases/year/rad/million population. There were no differences in other surgical conditions between the irradiated and nonirradiated groups. Persons irradiated under age 6 years had the highest excess risk for developing carcinomas. The incidence of thyroid neoplasms was approximately threefold higher in women than in men among the irradiated persons and among the controls, but the relative risk for the irradiated group of women was greater than the addition of the relative risks of the other groups. Low-dose radiation is instrumental in the development of both benign and malignant thyroid neoplasms.

  4. Tinea capitis due to Trichophyton soudanense with a papular IDE reaction in Northern Italy.

    PubMed

    Di Landro, A; Marchesi, L; Passera, M; Arosio, M

    2008-12-01

    A little boy from a Nigerian family who lives in a little industrialized village in the suburbs of Bergamo, (Northern Italy), has never been to his country but presented with tinea capitis and with a secondary papular pruritic eruption of the trunk. Fungal cultures analysis have shown the development of Trichophyton soudanense, an anthropophilic dermatophyte which is endemic in Africa, but only rarely reported in Italy and in other European countries. The growing racial mixing related to migratory movements is favoring, also in Italy, the integration of this strain with the species which are most commonly responsible for dermatophytoses and the appearance of papular IDE reactions which were only occasionally seen in the Italian children population. PMID:19169215

  5. Assessment of the efficacy and safety of a new treatment for head lice.

    PubMed

    Mac-Mary, Sophie; Messikh, Rafat; Jeudy, Adeline; Lihoreau, Thomas; Sainthillier, Jean-Marie; Gabard, Bernard; Schneider, Catherine; Auderset, Philippe; Humbert, Philippe

    2012-01-01

    Infestation with head lice is a widespread, persistent, and recurring issue leading to serious health problems if untreated. We are facing resistance phenomena to usual pediculicides and questions about their direct or cumulative toxicity. The aim of this trial was to assess the efficacy of a new product, free of chemical insecticides but with a physical effect. This product contains components whose antilice efficacy has already been demonstrated, as well as Andiroba oil which asphyxiates the lice and Quassia vinegar which dissolves the chitin of the nits (they are then inactivated). 30 patients with head lice infestation, aged 3-39 years, applied the treatment one to three times, 5 days apart. Cure was defined as the absence of live lice after 5, 10, or 14 days, and symptoms are usually associated with infestation. Easiness and safety of the treatment were assessed by the patients and/or their parents. Overall cure rates were 20% on D5 after one treatment, 37% on D10 after two treatments, and 90% on D14 after three treatments. Symptoms such as itch, scalp dryness, redness, and flakiness rapidly diminished. This treatment seems to be a beneficial addition or a valuable alternative to existing treatments, considering the total absence of chemical insecticides, the absence of drug-resistance induction in head lice, the absence of major toxicological risks compared with usual pediculicides, and the favourable patient use instructions. PMID:23209928

  6. Assessment of the Efficacy and Safety of a New Treatment for Head Lice

    PubMed Central

    Mac-Mary, Sophie; Messikh, Rafat; Jeudy, Adeline; Lihoreau, Thomas; Sainthillier, Jean-Marie; Gabard, Bernard; Schneider, Catherine; Auderset, Philippe; Humbert, Philippe

    2012-01-01

    Infestation with head lice is a widespread, persistent, and recurring issue leading to serious health problems if untreated. We are facing resistance phenomena to usual pediculicides and questions about their direct or cumulative toxicity. The aim of this trial was to assess the efficacy of a new product, free of chemical insecticides but with a physical effect. This product contains components whose antilice efficacy has already been demonstrated, as well as Andiroba oil which asphyxiates the lice and Quassia vinegar which dissolves the chitin of the nits (they are then inactivated). 30 patients with head lice infestation, aged 3–39 years, applied the treatment one to three times, 5 days apart. Cure was defined as the absence of live lice after 5, 10, or 14 days, and symptoms are usually associated with infestation. Easiness and safety of the treatment were assessed by the patients and/or their parents. Overall cure rates were 20% on D5 after one treatment, 37% on D10 after two treatments, and 90% on D14 after three treatments. Symptoms such as itch, scalp dryness, redness, and flakiness rapidly diminished. This treatment seems to be a beneficial addition or a valuable alternative to existing treatments, considering the total absence of chemical insecticides, the absence of drug-resistance induction in head lice, the absence of major toxicological risks compared with usual pediculicides, and the favourable patient use instructions. PMID:23209928

  7. Bioactivity of tea tree oil from Melaleuca alternifolia against sheep lice (Bovicola ovis Schrank) in vitro.

    PubMed

    James, P J; Callander, J T

    2012-07-01

    Tea tree oil (TTO) from the Australian native plant Melaleuca alternifolia has wide ranging bio-active properties, including insecticidal and repellent activity against arthropods. Furthermore, composition of commercially available Australian TTO is specified under an International Organization for Standardization standard (ISO 4730), reducing the potential for variable effects often noted with botanical pesticides. The effect of TTO, meeting the ISO standard for terpinen-4-ol chemotype, was tested against sheep lice (Bovicola ovis Schrank) in a series of laboratory studies. Immersion of wool for 60s in formulations containing concentrations of 1% TTO and above caused 100% mortality of adult lice and eggs. Exposure to vapours from TTO, delivered as droplets in fumigation chambers and when applied to wool also caused high mortality in both lice and eggs. The main active component of TTO in the fumigant tests was terpinen-4-ol. Treated surface assays and tests with wool where the formulation was allowed to dry before exposure of lice indicated low persistence. These studies demonstrate that TTO is highly toxic to sheep lice and active at concentrations that suggest potential for the development of TTO-based ovine lousicides. PMID:22398149

  8. LiCe9Mo16O35

    PubMed Central

    Gougeon, Patrick; Gall, Philippe

    2012-01-01

    The structure of lithium nona­cerium hexa­deca­molybdenum penta­trideca­oxide, LiCe9Mo16O35, is isotypic with LiNd9Mo16O35 [Gougeon Gall, Cuny, Gautier, Le Polles, Delevoye & Trebosc (2011 ▶). Chem. Eur. J. 17, 13806–13813]. It is characterized by Mo16O26 iO10 a units (where i = inner and a = apical) containing Mo16 clusters that share some of their O atoms to form infinite molybdenum cluster chains running parallel to the b axis and separated by Li+ and Ce3+ cations. The Mo16 cluster units are centred at Wyckoff positions 2c and have point-group symmetry 2/m. The Li+ atom, in a flattened octa­hedron of O atoms, is in a 2a Wyckoff position with 2/m symmetry. The Ce3+ cations have coordination numbers to the O atoms of 6, 9 or 10. Two Ce, two Mo and five O atoms lie on sites with m symmetry (Wyckoff site 4i), and one Ce and one O atom on sites with 2/m symmetry (Wyckoff sites 2b and 2d, respectively). PMID:22412396

  9. Insecticide resistance in head lice: clinical, parasitological and genetic aspects.

    PubMed

    Durand, R; Bouvresse, S; Berdjane, Z; Izri, A; Chosidow, O; Clark, J M

    2012-04-01

    Insecticide treatment resistance is considered to be a major factor in the increasing number of infestations by head lice. The large insecticide selection pressure induced by conventional topical pediculicides has led to the emergence and spread of resistance in many parts of the world. Possible mechanisms of resistance include accelerated detoxification of insecticides by enzyme-mediated reduction, esterification, oxidation that may be overcome by synergistic agents such as piperonyl butoxide, alteration of the binding site, e.g. altered acetylcholinesterase or altered nerve voltage-gated sodium channel, and knockdown resistance (kdr). Clinical, parasitological and molecular data on resistance to conventional topical pediculicides show that treatments with neurotoxic insecticides have suffered considerable loss of activity worldwide. In particular, resistance to synthetic pyrethroids has become prominent, probably because of their extensive use. As other treatment options, including non-insecticidal pediculicides such as dimeticone, are now available, the use of older insecticides, such as lindane and carbaryl, should be minimized, owing to their loss of efficacy and safety concerns. The organophosphorus insecticide malathion remains effective, except in the UK, mostly in formulations that include terpineol. PMID:22429458

  10. Epidemiological comparative study of pediculosis capitis among primary school children in Fayoum and Minofiya governorates, Egypt.

    PubMed

    Abd El Raheem, Talal A; El Sherbiny, Naglaa A; Elgameel, Alkasseem; El-Sayed, Ghada A; Moustafa, Nada; Shahen, Sally

    2015-04-01

    Pediculosis is a frequent public health problem. The pattern and prevalence of Pediculosis is dependent on many socio-demographic and economic factors. It is common in schoolchildren especially primary level; it may affect their learning performance. This study aimed to determine the prevalence of head louse among primary students, in Fayoum and Bagor districts, and explore the predisposing factors of head louse infestation in both public and private schools. The study was a cross-sectional descriptive study, conducted in two governorates: Fayoum and Minofiya governorates which represent upper and lower Egypt respectively during the academic year of 2012-2013. The students were selected from different grades with a total of 10,935 students. The prevalence of head lice in the study group was 16.7 %. The incidence was higher in public schools 20.7 % than private schools 9.04 % and in girls 25.8 % more than boys, especially covered hair girls 6.2 %. There was a socio-demographic influence of louse infestation on residence, presence of water supply, number of house rooms, and number of family member. It is concluded that head lice are a common childhood problem related to poor hygiene and socioeconomic status. There is a need for collaboration effort between family, school, community, and media, to create an environment that establishes healthy behaviors and health promotion. PMID:25086565