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Sample records for head louse infestation

  1. Plastic detection comb better than visual screening for diagnosis of head louse infestation.

    PubMed

    Balcioglu, C; Burgess, I F; Limoncu, M E; Sahin, M T; Ozbel, Y; Bilaç, C; Kurt, O; Larsen, K S

    2008-10-01

    Finding lice can be difficult in head louse infestation. We compared a new louse detection comb with visual inspection. All children in two rural Turkish schools were screened by the two methods. Those with lice were offered treatment and the results monitored by detection combing. Children with nits only were re-screened to identify latent infestations. Using visual inspection we found 214/461 children (46%) with nits but only 30 (6.5%) with live lice. In contrast detection combing found 96 (21%) with live lice, of whom 20 had no nits. Detection combing was 3.84 times more effective than visual inspection for finding live lice. Only 10/138 (7.2%) children with nits and no lice were found to have active infestation by day 16. We found that the detection comb is significantly (P<0.001) more effective than visual screening for diagnosis; that nits are not a good indicator of active infestation; and that treatment with 1% permethrin was 89.6% effective. PMID:18177517

  2. 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

  3. Soya oil-based shampoo superior to 0.5% permethrin lotion for head louse infestation

    PubMed Central

    Burgess, Ian F; Kay, Katrina; Burgess, Nazma A; Brunton, Elizabeth R

    2011-01-01

    Background This was a randomized, assessor-blind, controlled comparison of a soya oil- based medical device shampoo with a medicinal permethrin lotion in an alcohol vehicle for treatment of head louse infestation to generate data suitable for a regulatory submission to achieve reimbursable status for the shampoo product. Methods We treated 91 children and adults, divided between two sites, on two occasions 9 days apart. Participants washed their hair and towel-dried it before treatment. The shampoo was used twice for 30 minutes each time. The lotion was used for 30 minutes followed by rinsing. Assessments were made by dry detection combing on days 2, 9, 11, and 14 after the first treatment. According to present knowledge, this combing technique does not influence the overall head louse populations or outcome of treatment. Results The soya oil shampoo was significantly (P < 0.01) more effective than the lotion for both intention to treat (62.2% versus 34.8% successful treatment) and per-protocol (74.3% versus 36.8% success) groups. Post-treatment assessments showed the necessity for repeat treatment, but that a 9-day interval was too long because if eggs hatched after the first treatment, the lice could grow old enough to lay eggs before the second treatment. Conclusion The soya oil-based shampoo was more effective than the permethrin lotion, more cosmetically acceptable, and less irritant. PMID:22915928

  4. Tocopheryl acetate 20% spray for elimination of head louse infestation: a randomised controlled trial comparing with 1% permethrin creme rinse

    PubMed Central

    2013-01-01

    Background Tocopheryl acetate is viscous oily fluid used in a range of preparations for skin and scalp care in Italy. Observational and in vitro data have suggested a high level of efficacy against head louse infestation. The purpose of this investigation was to confirm the activity of tocopheryl acetate in a clinical setting in comparison with a standard widely used preparation. Methods A spray formulation containing tocopheryl acetate 20% in cyclomethicone was compared with permethrin 1% creme rinse for treatment of head louse infestation in a randomised, assessor blind, trial. Forty-five people were treated on two occasions 7 days apart. The spray was applied to dry hair for 20 minutes then washed. Participants treated with permethrin washed their hair and towel dried it before treatment for 10 minutes. Assessments were made by dry detection combing 1, 6, 9, and 14 days after first treatment. Results The tocopheryl acetate 20% spray was significantly (p = 0.033) more effective than permethrin 1%, using intention to treat worst case analysis, in which there were 13/23 (56.5%) successful treatments for tocopheryl acetate compared with 5/22 (22.7%) for permethrin. After unprecedented issues of re-infestation within households had been taken into account the underlying cure rate was 17/23 (73.9%) for tocopheryl acetate compared with 5/22 (22.7%), Odds Ratio 9.63 (95% CI, 2.46 to 37.68) (p < 0.001). Conclusions The tocopheryl acetate spray was significantly more effective than the permethrin product, was cosmetically acceptable, and not affected by current problems with resistance. Trial registration Current Controlled Trials ISRCTN45553737. PMID:24004959

  5. Single application of 4% dimeticone liquid gel versus two applications of 1% permethrin creme rinse for treatment of head louse infestation: a randomised controlled trial

    PubMed Central

    2013-01-01

    Background A previous study indicated that a single application of 4% dimeticone liquid gel was effective in treating head louse infestation. This study was designed to confirm this in comparison with two applications of 1% permethrin. Methods We have performed a single centre parallel group, randomised, controlled, open label, community based trial, with domiciliary visits, in Cambridgeshire, UK. Treatments were allocated through sealed instructions derived from a computer generated list. We enrolled 90 children and adults with confirmed head louse infestation analysed by intention to treat (80 per-protocol after 4 drop outs and 6 non-compliant). The comparison was between 4% dimeticone liquid gel applied once for 15 minutes and 1% permethrin creme rinse applied for 10 minutes, repeated after 7 days as per manufacturer’s directions. Evaluated by elimination of louse infestation after completion of treatment application regimen. Results Intention to treat comparison of a single dimeticone liquid gel treatment with two of permethrin gave success for 30/43 (69.8%) of the dimeticone liquid gel group and 7/47 (14.9%) of the permethrin creme rinse group (OR 13.19, 95% CI 4.69 to 37.07) (p < 0.001). Per protocol results were similar with 27/35 (77.1%) success for dimeticone versus 7/45 (15.6%) for permethrin. Analyses by household gave essentially similar outcomes. Conclusions The study showed one 15 minute application of 4% dimeticone liquid gel was superior to two applications of 1% permethrin creme rinse (p < 0.001). The low efficacy of permethrin suggests it should be withdrawn. Trial registration Current Controlled Trials ISRCTN88144046. PMID:23548062

  6. 1,2-Octanediol, a Novel Surfactant, for Treating Head Louse Infestation: Identification of Activity, Formulation, and Randomised, Controlled Trials

    PubMed Central

    Burgess, Ian F.; Lee, Peter N.; Kay, Katrina; Jones, Ruth; Brunton, Elizabeth R.

    2012-01-01

    Background Interest in developing physically active pediculicides has identified new active substances. The objective was to evaluate a new treatment for clinical efficacy. Methods and Findings We describe the selection of 1,2-octanediol as a potential pediculicide. Clinical studies were community based. The main outcome measure was no live lice, after two treatments, with follow up visits over 14 days. Study 1 was a proof of concept with 18/20 (90%) participants cured. Study 2 was a multicentre, parallel, randomised, observer-blind study (520 participants) that compared 0.5% malathion liquid with 1,2-octanediol lotion (20% alcohol) applied 2–2.5 hours or 8 hours/overnight. 1,2-octanediol lotion was significantly (p<0.0005) more effective with success for 124/175 (70.9%) RR = 1.50 (97.5% CI, 1.22 to 1.85) for 2–2.5 hours, and 153/174 (87.9%) RR = 1.86 (97.5% CI, 1.54 to 2.26) for 8 hours/overnight compared with 81/171 (47.4%) for malathion. Study 3, a two centre, parallel, randomised, observer-blind study (121 participants), compared 1,2-octanediol lotion, 2–2.5 hours with 1,2-octanediol alcohol free mousse applied for 2–2.5 hours or 8 hours/overnight. The mousse applied for 8 hours/overnight cured 31/40 (77.5%), compared with 24/40 (60.0%) for lotion (RR = 1.29, 95% CI, 0.95 to 1.75; NNT = 5.7) but mousse applied for 2–2.5 hours 17/41 (41.5%) was less effective than lotion (RR = 0.69, 95% CI, 0.44 to 1.08). Adverse events were more common using 1,2-octanediol lotion at both 2–2.5 hours (12.0%, p = 0.001) and 8 hours/overnight (14.9%, p<0.0005), compared with 0.5% malathion (2.3%). Similar reactions were more frequent (p<0.045) using lotion compared with mousse. Conclusions 1,2-octanediol was found to eliminate head louse infestation. It is believed to disrupt the insect's cuticular lipid, resulting in dehydration. The alcohol free mousse is more acceptable exhibiting significantly fewer adverse reactions. Trial registrations

  7. Clinical trial showing superiority of a coconut and anise spray over permethrin 0.43% lotion for head louse infestation, ISRCTN96469780.

    PubMed

    Burgess, Ian F; Brunton, Elizabeth R; Burgess, Nazma A

    2010-01-01

    Permethrin is the most widely used pediculicide, but evidence of resistance from several countries and anecdotal reports from Germany suggest that permethrin lotion is now less effective. We designed a randomized, controlled, parallel group trial involving 100 participants with active head louse infestation to investigate the activity of a coconut and anise spray and to see whether permethrin lotion is still effective, using two applications of product 9 days apart. The spray was significantly more successful (41/50, 82.0%) cures compared with permethrin (21/50, 42.0%; p < 0.0001, difference 40.0%, 95% confidence interval of 22.5% to 57.5%). Per-protocol success was 83.3% and 44.7%, respectively. Thirty-three people reported irritant reactions following alcohol contact with excoriated skin. We concluded that, although permethrin lotion is still effective for some people, the coconut and anise spray can be a significantly more effective alternative treatment. PMID:19343362

  8. Prevention of head louse infestation: a randomised, double-blind, cross-over study of a novel concept product, 1% 1,2-octanediol spray versus placebo

    PubMed Central

    Burgess, Ian F; Brunton, Elizabeth R; French, Rebecca; Burgess, Nazma A

    2014-01-01

    Objectives To determine whether regular use of a spray containing 1,2-octanediol 1%, which has been shown to inhibit survival of head lice, is able to work as a preventive against establishment of new infestations. Setting Randomised, double-blind, cross-over, community study in Cambridgeshire, UK. Participants 63 male and female schoolchildren aged 4–16 years judged to have a high risk of recurrent infestation. Only the youngest member of a household attending school participated. Interventions Participants were treated to eliminate lice, randomised between 1% octanediol or placebo sprays for 6 weeks then crossed-over to the other spray for 6 weeks. Parents applied the sprays at least twice weekly or more frequently if the hair was washed. Investigators monitored weekly for infestation and replenished supplies of spray. Primary and secondary outcome measures The primary endpoint was the time taken until the first infestation event occurred. The secondary measure was safety of the product in regular use. Results Intention-to-treat analysis found a total of 32 confirmed infestations in 20 participants, with 9 of them infested while using both products. In these nine participants the time to first infestation showed a significant advantage to 1% octanediol (p=0.0129). Per-protocol analysis showed only trends because the population included was not large enough to demonstrate significance. There were no serious adverse events and only two adverse events possibly related to treatment, one was a case of transient erythema and another of a rash that resolved after 5 days. Conclusions Routine use of 1% octanediol spray provided a significant level of protection from infestation. It was concluded that this product is effective if applied regularly and thoroughly. Trial registration number ISRCTN09524995. PMID:24879825

  9. Can head louse repellents really work? Field studies of piperonal 2% spray

    PubMed Central

    Brown, Christine M.; Burgess, Nazma A.; Kaufman, Judith

    2014-01-01

    Background. Many families find regular checking of children’s heads for head louse infestation too onerous and would prefer to be able to prevent infestation by use of a topical application that deters lice from infesting the head. Identification in the laboratory of a repellent activity for piperonal provided the basis for developing a spray product to repel lice. Methods. A proof of principle field study in Dhaka, Bangladesh, compared the effect of using 2% piperonal spray with that of a placebo in 105 children and adults from three communities with infestation levels close to 100%. All participants were treated for infestation and subsequent incidence of reinfestation monitored daily by investigators. A second randomised, controlled, double blind, study in North London, UK, evaluated the effect of the product in normal use. One hundred and sixty-three children from schools with a high level (20–25%) of infestation were treated and confirmed louse free and randomly divided between 2% piperonal, a placebo spray, and a control group for up to 22 weeks. Parents applied the spray and monitored for infestation. Regular investigator visits confirmed the parental monitoring and replenished supplies of spray. Results. In Dhaka, over 18 days there were only 4 infestations in the piperonal group and 8 in the placebo group. This difference was not significant (p = 0.312). In North London, there were 41 cases of infestation over the course of the study. Although there were fewer infestations in the piperonal group, analysis of time to first infestation showed a no significant (p = 0.4368) difference between groups. Conclusion. Routine use of 2% piperonal spray in communities with a high prevalence of head louse infestation may provide some protection from infestation. However, the difference between use of the product and no active intervention was sufficiently small that regular checking for presence of lice is likely to be a more practical and cost effective approach

  10. Comparison of phenothrin mousse, phenothrin lotion, and wet-combing for treatment of head louse infestation in the UK: a pragmatic randomised, controlled, assessor blind trial.

    PubMed

    Burgess, Ian F; Brown, Christine M; Nair, Pat

    2014-01-01

    In this investigation of effectiveness of an alternative pediculicide dosage form, we recruited 228 children and 50 adult participants from Bedfordshire, UK, to a randomised, controlled, assessor blind trial comparing two insecticide products with mechanical removal of lice as a control group.  Participants using insecticide were treated with either the investigative 0.5% phenothrin mousse, for 30 minutes, or 0.2% phenothrin lotion, for 2 hours as the reference product.  Both treatments were applied only once, followed by shampoo washing.  Those treated by wet-combing with conditioner were combed 4 times over 12 days.  Parents/carers carried out the treatments to mimic normal consumer use.  The outcome measure was the absence of lice, 14 days after treatment for the insecticides, and up to 14 days after completion of combing.  Intention to treat analysis of the outcomes for 275 participants showed success for phenothrin mousse in 21/105 (20.0%), in 23/107 (21.5%) for phenothrin lotion, and in 12/63 (19.1%) for wet-combing.  People receiving mousse were 1.07 (95% CI, 0.63 to 1.81) times more likely to still have lice after treatment compared with those treated with lotion. The group of participants who received the wet combing treatment were 1.13 (95% CI, 0.61 to 2.11) times more likely to still have lice after the treatment.  None of the treatments was significantly (p < 0.05) more effective than any other. This study was carried out in an area where moderate resistance to phenothrin was demonstrated after the study by using a bioassay.  Analysis of post treatment assessments found that failure of insecticides to kill louse eggs had influenced the outcome. PMID:25254106

  11. Comparison of phenothrin mousse, phenothrin lotion, and wet-combing for treatment of head louse infestation in the UK: a pragmatic randomised, controlled, assessor blind trial

    PubMed Central

    Burgess, Ian F.; Brown, Christine M.; Nair, Pat

    2014-01-01

    In this investigation of effectiveness of an alternative pediculicide dosage form, we recruited 228 children and 50 adult participants from Bedfordshire, UK, to a randomised, controlled, assessor blind trial comparing two insecticide products with mechanical removal of lice as a control group.  Participants using insecticide were treated with either the investigative 0.5% phenothrin mousse, for 30 minutes, or 0.2% phenothrin lotion, for 2 hours as the reference product.  Both treatments were applied only once, followed by shampoo washing.  Those treated by wet-combing with conditioner were combed 4 times over 12 days.  Parents/carers carried out the treatments to mimic normal consumer use.  The outcome measure was the absence of lice, 14 days after treatment for the insecticides, and up to 14 days after completion of combing.  Intention to treat analysis of the outcomes for 275 participants showed success for phenothrin mousse in 21/105 (20.0%), in 23/107 (21.5%) for phenothrin lotion, and in 12/63 (19.1%) for wet-combing.  People receiving mousse were 1.07 (95% CI, 0.63 to 1.81) times more likely to still have lice after treatment compared with those treated with lotion. The group of participants who received the wet combing treatment were 1.13 (95% CI, 0.61 to 2.11) times more likely to still have lice after the treatment.  None of the treatments was significantly (p < 0.05) more effective than any other. This study was carried out in an area where moderate resistance to phenothrin was demonstrated after the study by using a bioassay.  Analysis of post treatment assessments found that failure of insecticides to kill louse eggs had influenced the outcome. PMID:25254106

  12. Bio-ecology of the louse, Upupicola upupae, infesting the Common Hoopoe, Upupa epops.

    PubMed

    Agarwal, G P; Ahmad, Aftab; Rashmi, Archna; Arya, Gaurav; Bansal, Nayanci; Saxena, A K

    2011-01-01

    Abstract The population characteristics of the louse, Upupicola upupae (Shrank) (Mallophaga: Philopteridae: Ishnocera), infesting the Common Hoopae, Upupa epops L. (Aves: Upupiformes), were recorded during 2007-08 in District Rampur, Uttar Pradesh India. The pattern of frequency distribution of the louse conformed to the negative binomial model. The lice and its nits were reared in vitro at 35 ± 1° C, 75-82 % RH, on a feather diet. The data obtained was used to construct the life table and to determine the intrinsic rate of natural increase (0.035 female/day), the net reproductive rate was 3.67 female eggs/female, the generation time was 37 days, and the doubling time of the population was 19 days. The chaetotaxy of the three nymphal instars has also been noted to record their diagnostic characteristics. Information on egg morphology and antennal sensilla is also presented. PMID:21861650

  13. The sex ratio distortion in the human head louse is conserved over time

    PubMed Central

    Perotti, M Alejandra; Catalá, Silvia S; Ormeño, Analía del V; Żelazowska, Monika; Biliński, Szczepan M; Braig, Henk R

    2004-01-01

    Background At the turn of the 19th century the first observations of a female-biased sex ratio in broods and populations of the head louse, Pediculus humanus capitis, had been reported. A study by Buxton in 1940 on the sex ratio of lice on prisoners in Ceylon is still today the subject of reanalyses. This sex ratio distortion had been detected in ten different countries. In the last sixty years no new data have been collected, especially on scalp infestations under economically and socially more developed conditions. Results Here we report a female bias of head lice in a survey of 480 school children in Argentina. This bias is independent of the intensity of the pediculosis, which makes local mate competition highly unlikely as the source of the aberrant sex ratio; however, other possible adaptive mechanisms cannot be discounted. These lice as well as lice from pupils in Britain were carrying several strains of the endosymbiotic bacterium Wolbachia pipientis, one of the most wide spread intracellular sex ratio distorters. Similar Wolbachia strains are also present in the pig louse, Haematopinus suis, suggesting that this endosymbiont might have a marked influence on the biology of the whole order. The presence of a related obligate nutritional bacterium in lice prevents the investigation of a causal link between sex ratio and endosymbionts. Conclusions Regardless of its origin, this sex ratio distortion in head lice that has been reported world wide, is stable over time and is a remarkable deviation from the stability of frequency-dependent selection of Fisher's sex ratio. A female bias first reported in 1898 is still present over a hundred years and a thousand generations later. PMID:15140268

  14. Treatment of natural infestations of the biting louse (Werneckiella equi) on horses using triflumuron, a benzoylurea derivative insect growth regulator.

    PubMed

    Lowden, Stewart; Gray, Stephen; Dawson, Kim

    2007-09-30

    The horse biting louse (Werneckiella equi) is a common global equine ectoparasite. To our knowledge, benzoyl(phenyl)urea insecticides (triflumuron, diflubenzuron) commonly used as sheep lousicides, have not been evaluated for efficacy against W. equi. The aim of this study was to determine louse control efficacy, general wellness and dermal safety following triflumuron application as a backline pour-on to horses. Two efficacy trials using 25 adult naturally infested lousy horses, and a dermal safety trial using 10 adult louse-free horses were conducted over a 14-month period. Lousy animals were selected by assessment of their lice status prior to treatment. For the efficacy trial, the triflumuron product was applied at a dose of 2.5mg triflumuron per kg bodyweight (1 mL product per 10 kg bodyweight). For the safety study, triflumuron was applied at a 3x clinical dose of 7.5 mg triflumuron per kg bodyweight (3 mL product per 10 kg bodyweight). In our first efficacy trial, 100% lousicidal efficacy was achieved by day 44 post-treatment. In our second trial, no lice were identified on horses by day 71 post-treatment. In the safety trial, no adverse effects were seen. Results of this study demonstrate that the off-label, experimental pour-on application of triflumuron at 2.5 mg/kg bodyweight is convenient, highly effective and safe (at 3x the clinical dose) for the treatment of the horse biting louse, W. equi. PMID:17689014

  15. Knockdown Resistance Allele Frequencies in North American Head Louse (Anoplura: Pediculidae) Populations

    PubMed Central

    Yoon, Kyong Sup; Previte, Domenic J.; Hodgdon, Hilliary E.; Poole, Bryan C.; Kwon, Deok Ho; El-Ghar, Gamal E. Abo; Lee, Si Hyeock; Clark, J. Marshall

    2014-01-01

    The study examines the extent and frequency of a knockdown-type resistance allele (kdr type) in North American populations of human head lice. Lice were collected from 32 locations in Canada and the United States. DNA was extracted from individual lice and used to determine their zygosity using the serial invasive signal amplification technique to detect the kdr-type T917I (TI) mutation, which is most responsible for nerve insensitivity that results in the kdr phenotype and permethrin resistance. Previously sampled sites were resampled to determine if the frequency of the TI mutation was changing. The TI frequency was also reevaluated using a quantitative sequencing method on pooled DNA samples from selected sites to validate this population genotyping method. Genotyping substantiated that TI occurs at high levels in North American lice (88.4%). Overall, the TI frequency in U.S. lice was 84.4% from 1999 to 2009, increased to 99.6% from 2007 to 2009, and was 97.1% in Canadian lice in 2008. Genotyping results using the serial invasive signal amplification reaction (99.54%) and quantitative sequencing (99.45%) techniques were highly correlated. Thus, the frequencies of TI in North American head louse populations were found to be uniformly high, which may be due to the high selection pressure from the intensive and widespread use of the pyrethrins- or pyrethroid-based pediculicides over many years, and is likely a main cause of increased pediculosis and failure of pyrethrins- or permethrin-based products in Canada and the United States. Alternative approaches to treatment of head lice infestations are critically needed. PMID:24724296

  16. Knockdown resistance allele frequencies in North American head louse (Anoplura: Pediculidae) populations.

    PubMed

    Yoon, Kyong Sup; Previte, Domenic J; Hodgdon, Hilliary E; Poole, Bryan C; Kwon, Deok Ho; El-Ghar, Gamal E Abo; Lee, Si Hyeock; Clark, J Marshall

    2014-03-01

    The study examines the extent and frequency of a knockdown-type resistance allele (kdr type) in North American populations of human head lice. Lice were collected from 32 locations in Canada and the United States. DNA was extracted from individual lice and used to determine their zygosity using the serial invasive signal amplification technique to detect the kdr-type T917I (TI) mutation, which is most responsible for nerve insensitivity that results in the kdr phenotype and permethrin resistance. Previously sampled sites were resampled to determine if the frequency of the TI mutation was changing. The TI frequency was also reevaluated using a quantitative sequencing method on pooled DNA samples from selected sites to validate this population genotyping method. Genotyping substantiated that TI occurs at high levels in North American lice (88.4%). Overall, the TI frequency in U.S. lice was 84.4% from 1999 to 2009, increased to 99.6% from 2007 to 2009, and was 97.1% in Canadian lice in 2008. Genotyping results using the serial invasive signal amplification reaction (99.54%) and quantitative sequencing (99.45%) techniques were highly correlated. Thus, the frequencies of TI in North American head louse populations were found to be uniformly high, which may be due to the high selection pressure from the intensive and widespread use of the pyrethrins- or pyrethroid-based pediculicides over many years, and is likely a main cause of increased pediculosis and failure of pyrethrins- or permethrin-based products in Canada and the United States. Alternative approaches to treatment of head lice infestations are critically needed. PMID:24724296

  17. Neem seed extract shampoo, Wash Away Louse, an effective plant agent against Sarcoptes scabiei mites infesting dogs in Egypt.

    PubMed

    Abdel-Ghaffar, Fathy; Al-Quraishy, Saleh; Sobhy, Hassan; Semmler, Margit

    2008-12-01

    In the present study, the efficacy of water-free neem seed extract shampoo Wash Away Louse, provided by Alpha-Biocare GmbH, Düsseldorf (Germany), was investigated against Sarcoptes scabiei infesting dogs in Egypt. Ten naturally infested dogs were collected from different areas in the Nile delta. The occurrence of lesions, hair loss, and skin inflammation were regarded as signs of infestation and proved by detection of adult parasites and their developmental stages in scrapings of infested lesions. Adequate amount of the provided shampoo was applied topically and spread on the infested areas daily for 14 successive days. Scraping examinations were used to follow up the healing process. At day 7 of application, four dogs were completely free of mites as was proven by the disappearance of adults and/or any developmental stages of mites. The remaining six dogs showed a clear decrease in mite counts. By the end of the treatment (after 14 days), only a small number of mites were found in two dogs, while eight dogs were completely cured as was proven by mite counts and disappearance of clinical signs. No remarkable signs of side effects or adverse reactions were observed throughout the study. PMID:18769941

  18. 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

  19. Epidemiology and control of human head louse in Malaysia.

    PubMed

    Sinniah, B; Sinniah, D; Rajeswari, B

    1983-12-01

    A survey of 4.112 primary school children living in and around Kuala Lumpur, Malaysia, revealed that 12.9% of the children were infested with Pediculus humanus capitis. Indians (28.3%) and Malays (18.9%) have a higher prevalence than Chinese (4.6%). The higher prevalence among Indians and Malays correlates well with their lower socio-economic status in the community; long hair also contributes to the higher rates of pediculosis among them. The prevalence rate was found to be related to socio-economic status, length of hair, family size, age, crowding and personal hygiene. Treatment with 0.2% and 0.5% malathion in coconut oil gave cure rates of 93% and 100%. Treatment with gammexane and actellic at 0.5% concentration gave a cure rate of 100% against adults and nymphs of Pediculus humanus capitis. PMID:6670116

  20. Determination of knockdown resistance allele frequencies in global human head louse populations using the serial invasive signal amplification reaction

    PubMed Central

    Hodgdon, Hilliary E.; Yoon, Kyong Sup; Previte, Domenic J.; Kim, Hyo Jeong; Aboelghar, Gamal E.; Lee, Si Hyeock; Clark, J. Marshall

    2010-01-01

    BACKGROUND Pediculosis is the most prevalent parasitic infestation of humans. Resistance to pyrethrin- and pyrethroid-based pediculicides is due to knockdown (kdr)-type point mutations in the voltage-sensitive sodium channel α-subunit gene. Early detection of resistance is crucial for the selection of effective management strategies. RESULTS Kdr allele frequencies of lice from 14 countries were determined using serial invasive signal amplification reaction. Lice collected from Uruguay, UK and Australia had kdr allele frequencies of 100% while lice from Ecuador, Papua New Guinea, South Korea and Thailand had kdr allele frequencies of 0%. The remaining 7 countries investigated, including seven US populations, two Argentina, Brazil, Denmark, Czech Republic, Egypt and Israel, displayed variable kdr allele frequencies, ranging from 11% to 97%. CONCLUSION The newly developed and validated SISAR method is suitable for accurate monitoring of kdr allele frequencies in head lice. Proactive management is needed where kdr-type resistance is not yet saturated. Based on sodium channel insensitivity and its occurrence in louse populations resistant to pyrethrin- and pyrethroid-based pediculicides, the T917I mutation appears a key marker for resistance. Results from the Egyptian population, however, indicate that phenotypic resistance of lice with single or double mutations (M815I and/or L920F) should also be determined. PMID:20564731

  1. Determination of permethrin resistance allele frequency of human head louse populations by quantitative sequencing.

    PubMed

    Kwon, Deok Ho; Yoon, Kyong Sup; Strycharz, Joseph P; Clark, J Marshall; Lee, Si Hyeock

    2008-09-01

    A quantitative sequencing (QS) protocol that detects the frequencies of sodium channel mutations (M815I, T917I, and L920F) responsible for knockdown resistance in permethrin-resistant head lice (Pediculus humanus capitis De Geer) was tested as a population genotyping method for use as a preliminary resistance monitoring tool. Genomic DNA fragments of the sodium channel a-subunit gene that encompass the three mutation sites were polymerase chain reaction (PCR)-1 amplified from individual head lice with either resistant or susceptible genotypes, and combined in various ratios to generate standard DNA template mixtures for QS. After sequencing, the signal ratios between resistant and susceptible nucleotides were calculated and plotted against the corresponding resistance allele frequencies. Quadratic regression coefficients of the plots were close to 1, demonstrating that the signal ratios are highly correlated with the resistance allele frequencies. Resistance allele frequencies predicted by QS, using either "pooled DNA" (DNA extracted from individual louse specimens and pooled) or "pooled specimen DNA" (DNA simultaneously extracted from multiple louse specimens), agreed well with those determined by individual sequencing, confirming the reliability and accuracy of QS as a population genotyping method and validating our approach of using the pooled specimen DNA as the DNA template for QS. Our protocol for QS was determined to be highly reliable for the prediction of resistance allele frequencies higher than approximately 7.4% at the 95% confidence level. According to the resistance allele frequencies determined by QS, pyrethroid resistance varies substantially among different geographical regions, emphasizing the importance of early resistance detection and proper management strategies. PMID:18826035

  2. Wild salmonids and sea louse infestations on the west coast of Scotland: sources of infection and implications for the management of marine salmon farms.

    PubMed

    Butler, James R A

    2002-06-01

    The sea louse (Lepeophtheirus salmonis Krøyer) is a major health problem for both farmed and wild salmonids. This paper investigates louse epidemiology and management in the salmon-farming zone of western Scotland. Based on a review of the marine ecology of wild salmon (Salmo salar L) and sea trout (Salmo trutta L), and catch and farm production statistics, best estimates were made for numbers of wild and farm hosts present in coastal waters in March-June 2000. Applying data for ovigerous female louse infections and fecundity, the sources and risks of larval transmission to wild salmon and sea trout were modelled. Farm salmon in the second spring of production were the primary host group (98% of fish), while numbers of wild salmonids (< 1%) and escaped farm salmon (2%) were relatively insignificant. Farm salmon produced 97% of louse eggs at high levels (eight ovigerous lice per fish), and 78% at low levels (one per fish). Wild salmonids produced < 1% of eggs under both scenarios, but escaped farm salmon produced 3% and 21%, respectively. All hosts potentially cross-infect one another, but farm salmon are more likely to infect wild and farm smolts, and also other farm salmon. Monitoring of lice on sea trout in June 1998-2000 by the Association of West Coast Fisheries Trusts corroborated the model's conclusions. Localised epizootics occurred every year and coincided with the presence of ovigerous lice on local farms. In areas of mixed-year class production on farms, epizootics were evident every spring, but occurred every second spring in areas of single-year class production. In 1998-2000 at least 14-40% of sea trout were infected with potentially lethal infestations of lice. Ovigerous louse levels of < 0.005 per fish were required on farm salmon in the spring of 2000 to produce less eggs than those emitted by wild salmonids. With the industry's continued expansion, and thus increased numbers of farm salmon, a target of zero ovigerous lice will be required on farms

  3. 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

  4. 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

  5. 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

  6. 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

  7. 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

  8. Ovicidal Response of NYDA Formulations on the Human Head Louse (Anoplura: Pediculidae) Using a Hair Tuft Bioassay

    PubMed Central

    STRYCHARZ, JOSEPH P.; LAO, ALICE R.; ALVES, ANNA-MARIA; CLARK, J. MARSHALL

    2012-01-01

    Using the in vitro rearing system in conjunction with the hair tuft bioassay, NYDA and NYDA without fragrances formulations (92% wt:wt dimeticones) were 100% ovicidal (0% of treated eggs hatched) after an 8-h exposure of the eggs of the human head louse (Pediculus humanus capitis De Geer) following the manufacturer’s instructions. Comparatively, 78 and 66% of eggs similarly exposed hatched after distilled deionized water or Nix (1% permethrin) treatments, respectively. NYDA and NYDA without fragrances formulations were also statistically and substantially more ovicidal than either distilled deionized water or Nix treatments after 10, 30 min, and 1 h exposures. Only the 10 min exposure of eggs to NYDA and NYDA without fragrances formulations resulted in hatched lice that survived to adulthood (5–8% survival). Of the lice that hatched from eggs exposed to NYDA formulations for 10 min, there were no significant differences in the time it took them to become adults, female fecundity or the viability of eggs laid by surviving females. The longevity of adults, however, was reduced after the 10 min treatments of eggs with NYDA and NYDA without fragrances formulations compared with either the distilled deionized water or Nix treatments. PMID:22493852

  9. Ovicidal response of NYDA formulations on the human head louse (Anoplura: Pediculidae) using a hair tuft bioassay.

    PubMed

    Strycharz, Joseph P; Lao, Alice R; Alves, Anna-Maria; Clark, J Marshall

    2012-03-01

    Using the in vitro rearing system in conjunction with the hair tuft bioassay, NYDA and NYDA without fragrances formulations (92% wt:wt dimeticones) were 100% ovicidal (0% of treated eggs hatched) after an 8-h exposure of the eggs of the human head louse (Pediculus humanus capitis De Geer) following the manufacturer's instructions. Comparatively, 78 and 66% of eggs similarly exposed hatched after distilled deionized water or Nix (1% permethrin) treatments, respectively. NYDA and NYDA without fragrances formulations were also statistically and substantially more ovicidal than either distilled deionized water or Nix treatments after 10, 30 min, and 1 h exposures. Only the 10 min exposure of eggs to NYDA and NYDA without fragrances formulations resulted in hatched lice that survived to adulthood (5-8% survival). Of the lice that hatched from eggs exposed to NYDA formulations for 10 min, there were no significant differences in the time it took them to become adults, female fecundity or the viability of eggs laid by surviving females. The longevity of adults, however, was reduced after the 10 min treatments of eggs with NYDA and NYDA without fragrances formulations compared with either the distilled deionized water or Nix treatments. PMID:22493852

  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. How long do louse eggs take to hatch? A possible answer to an age-old riddle.

    PubMed

    Burgess, I F

    2014-06-01

    There are no rigorous data on how long eggs of the head louse, Pediculus capitis (Phthiraptera: Pediculidae), take to hatch. Pediculicide users often report reinfestations after apparently successful treatments in the absence of infective contacts. This study aimed to resolve the question of whether some louse eggs hatch after the completion of treatment, thereby giving rise to a new infestation. Data were extracted from the records of lice collected after treatments in 20 clinical intervention trials. All datasets were eliminated except those in which only newly hatched louse nymphs were found prior to the final assessment. This excluded the possibility that new eggs were laid after the first treatment and thus any young lice found must have originated from eggs laid before the start of treatment. This identified 23 of 1895 (1.2%) records with evidence of louse nymphs emerging at 13 days or more after the first treatment, 3–6 days longer than previous estimates. Current treatment regimens for pediculicides of two applications 7–10 days apart appear inadequate, which may explain continuing infestation in the community. Therefore, it is suggested that a revised approach using three treatments applied at intervals of 1 week should prevent the survival of any nymphs and their development into a new generation of adults. PMID:24987776

  12. Pediatric ocular phthiriasis infestation.

    PubMed

    Kairys, D J; Webster, H J; Terry, J E

    1988-02-01

    Although pubic lice infestation of ocular regions is relatively uncommon, the optometrist needs to be aware of the diagnosis and treatment of louse-infested patients. A case report of ocular phthiriasis is presented along with a discussion of its etiology, clinical diagnosis and management. PMID:3361053

  13. 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

  14. 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

  15. 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.

  16. 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

  17. Seasonal dynamics of the flower head infestation of Smallanthus maculatus by two nonfrugivorous tephritids.

    PubMed

    Dzul-Cauich, José F; Hernández-Ortiz, Vicente; Parra-Tabla, Victor; Rico-Gray, Victor

    2014-01-01

    Seasonal dynamics of the capitula infested by Dictyotrypeta sp. and Rhynencina spilogaster (Steyskal) (Diptera: Tephritidae) was evaluated throughout the flowering cycle of their host plant the sunflower, Smallanthus maculatus (Cavanilles) Robinson (Asterales: Asteraceae). In central Veracruz, Mexico, along 16 consecutive weeks, a total of 1,017 mature capitula were collected, recording the presence and abundance of immature stages (larvae and pupae) and their related parasitoids. Both fly species were present throughout the entire season, with overall infestation of 51.5% of the capitula examined. However, Dictyotrypeta sp. infested 11.3%, representing about one-fifth of them, and R. spilogaster was most abundant infesting four times as many capitula (42.9%), whereas both species were found together in only 2.6% of the capitula examined. Based on the temporal occurrence of larvae and pupae into flower heads as well as their associated parasitoids and times of emergence, Dictyotrypeta sp. had two yearly generations, and it seems that the second generation could enter a seasonal diapause; in contrast, R. spilogaster was a univoltine species that entered diapause that lasted until the next year. PMID:25368091

  18. The use of the head louse as a remedy for jaundice in Spanish folk medicine: an overview

    PubMed Central

    2013-01-01

    Background In Spain, head lice are considered a therapeutic resource for the treatment of jaundice. All folk remedies based on the ingestion of these insects meet in the present document, previously dispersed among a large number of references. Methods An overview of the Spanish literature has been carried out. The most important databases have been consulted. All related works have been examined. Results Although the method of preparation is diverse and the dose varies, the primary recommendation is a transference ritual consisting of taking nine live lice for nine days on an empty stomach without the patient’s knowledge. This traditional knowledge survives in Spanish society, and constitutes an example of the interrelation between Spanish and Latin American folk medicines. Conclusions The survival of this therapy in the worldview of certain rural communities suggests the need to take into account the beliefs, ideas and behaviour patterns of popular culture in relation to health and disease. PMID:23876126

  19. 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

  20. 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 ...

  1. 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

  2. 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

  3. Hey! A Louse Bit Me!

    MedlinePlus

    ... Sledding, Skiing, Snowboarding, Skating Crushes What's a Booger? Hey! A Louse Bit Me! KidsHealth > For Kids > Hey! A Louse Bit Me! Print A A A ... For Kids For Parents MORE ON THIS TOPIC Hey! A Gnat Bit Me! Hey! A Flea Bit ...

  4. Spot-on Treatments of Diflubenzuron and Permethrin to Control a Guinea Pig Louse, Gliricola Porcelli (Phthiraptera: Gyropidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Guinea pigs (Cavia porcellus (L.)) (Rodentia: Caviidae) are pets and laboratory animals. They can be infested by a chewing louse, Gliricola porcelli (Schrank) (Phthiraptera: Gyropidae), which is fairly common in some animal rearing facilities, pet stores, and on wild guinea pigs. Infestation with G....

  5. 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

  6. Prevalence of Head Lice Infestation and Its Associated Factors among Primary School Students in Iran: A Systematic Review and Meta-analysis

    PubMed Central

    Moosazadeh, Mahmood; Afshari, Mahdi; Keianian, Hormoz; Nezammahalleh, Asghar; Enayati, Ahmad Ali

    2015-01-01

    Objectives Head lice infestation is one of the most important health problems, generally involving children aged 5–13 years. This study aims to estimate the prevalence of head lice infestation and its associated factors among primary school children using systematic review and meta-analysis methods. Methods Different national and international databases were searched for selecting the relevant studies using appropriate keywords, Medical Subject Heading terms, and references. Relevant studies with acceptable quality for meta-analysis were selected having excluded duplicate and irrelevant articles, quality assessment, and application of inclusion/exclusion criteria. With calculating standard errors according to binomial distribution and also considering the Cochrane's Q test as well as I-squared index for heterogeneity, pediculosis prevalence rate was estimated using Stata SE V.11 software. Results Forty studies met the inclusion criteria of this review and entered into the meta-analysis including 200,306 individuals. Using a random effect model, the prevalence (95% confidence interval) of head lice infestation among primary school children was estimated as 1.6% (1.2–2.05), 8.8% (7.6–9.9), and 7.4% (6.6–8.2) for boys, girls, and all the students, respectively. The infestation rate was found to be associated with low educational level of parents, long hair, family size, mother's job (housewife), father's job (worker/unemployed), using a common comb, lack of bathrooms in the house, and a low frequency of bathing. Conclusion This meta-analysis revealed that the prevalence of head lice infestation among Iranian primary school children is relatively high with more prevalence among girls. We also found that economic, social, cultural, behavioral, and hygienic factors are associated with this infestation. PMID:26835244

  7. 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

  8. Dermatologic infestations.

    PubMed

    Shmidt, Eugenia; Levitt, Jacob

    2012-02-01

    Head lice are transmitted by head to head contact. Optimal therapy includes malathion lotion 0.5% repeated in one week left on for 30 minutes to 8 hours. Spinosad topical suspension 0.9% repeated in one week left on for 10 minutes is another option. Scabies is transmitted mainly by direct contact but also via heavily infested fomites due to crusted scabies. Permethrin 5% cream to the body repeated in four days is often sufficient; however, scalp treatment with malathion lotion 0.5% is helpful in crusted scabies and in infested children. Oral ivermectin 200 mcg/kg is another option, repeated in four days. For scabies more than lice, fomites should be placed in a drier at 60 °C for 10 minutes to kill the arthropods. Treatment of close contacts in both cases will control outbreaks and repeated infestations. Both have been associated with methicillin-resistant Staphylococcus aureus infection. Bed bugs are a common cause for papular urticaria. Identification of the insect in the mattress or bedding confirms the diagnosis. Prevention involves encasing the mattress in a sealed plastic cover and extermination. Delusions of parasitosis is a diagnosis of exclusion that is best treated with an antipsychotic. PMID:22250620

  9. 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

  10. Treatment of Phthiriasis Palpebrarum and Crab Louse: Petrolatum Jelly and 1% Permethrin Shampoo

    PubMed Central

    Karabela, Yunus; Yardimci, Gurkan; Yildirim, Isik; Atalay, Eray; Karabela, Semsi Nur

    2015-01-01

    Phthiriasis palpebrarum is an uncommon cause of blepharoconjunctivitis in which Pthirus pubis infest the eyelashes. We report a case of unilateral phthiriasis palpebrarum with crab louse. A 45-year-old man presented with conjunctival hyperaemia and moderate itching associated with irritation, and crusty excretions of the eyelashes in the left eye. Careful slit-lamp examination revealed many lice and nits in left eye and mild conjunctival hyperaemia. No abnormality was found in the right eye. On dermatologic examination, only one louse was found at the pubic area. The patient was treated effectively with petrolatum jelly (Vaseline) and 1% permethrin shampoo (Kwellada 1% shampoo). At the end of the first week no louse or nit was present on eyelashes and pubic area. PMID:26451147

  11. Treatment of Phthiriasis Palpebrarum and Crab Louse: Petrolatum Jelly and 1% Permethrin Shampoo.

    PubMed

    Karabela, Yunus; Yardimci, Gurkan; Yildirim, Isik; Atalay, Eray; Karabela, Semsi Nur

    2015-01-01

    Phthiriasis palpebrarum is an uncommon cause of blepharoconjunctivitis in which Pthirus pubis infest the eyelashes. We report a case of unilateral phthiriasis palpebrarum with crab louse. A 45-year-old man presented with conjunctival hyperaemia and moderate itching associated with irritation, and crusty excretions of the eyelashes in the left eye. Careful slit-lamp examination revealed many lice and nits in left eye and mild conjunctival hyperaemia. No abnormality was found in the right eye. On dermatologic examination, only one louse was found at the pubic area. The patient was treated effectively with petrolatum jelly (Vaseline) and 1% permethrin shampoo (Kwellada 1% shampoo). At the end of the first week no louse or nit was present on eyelashes and pubic area. PMID:26451147

  12. Seasonal dynamics and variation among sheep in densities of the sheep biting louse, Bovicola ovis.

    PubMed

    James, P J; Moon, R D; Brown, D R

    1998-02-01

    Cyclic patterns and variations among sheep in numbers of Bovicola ovis are described in Polypay and Columbia ewes that were initially infested with equal numbers of lice and penned indoors continuously for 2 years. Bovicola ovis populations were censused at 3-4-week intervals at 69 body sites on each animal. In the second year of the study, the ewes were reinfested and half were mated. Louse populations were monitored on the resulting lambs from birth until 25 weeks of age. Strong seasonal cycles in louse numbers were observed on the ewes, with peaks in spring and troughs in summer. These cycles occurred in the absence of shearing, direct solar radiation or rainfall. Populations began to decline when daily mean and maximum temperatures were 11.5 degrees C and 15 degrees C, respectively, well below temperatures thought to cause warm season decline. Louse densities on Polypay ewes were approximately 10 times higher than on Columbias at most inspections. There were also large differences among sheep within breeds and sheep counts were highly correlated among dates, both within and between years. One third of the ewes failed to become infested despite having lice applied on five separate occasions and being penned together with other infested sheep. Pregnancy and lactation did not significantly affect louse numbers on the ewes. There was a significant negative correlation between louse counts and weight gains in the lambs, and lamb counts were significantly correlated with those of their dams up until, but not after, weaning. It is suggested that sheep may exert regulatory influences on lice which contribute to cycles in B. ovis populations. PMID:9512991

  13. Response of Grape Leaf Spectra to Phylloxera Infestation

    NASA Technical Reports Server (NTRS)

    Johnson, Lee F.

    1999-01-01

    During the 1993 growing season, leaf reflectance and chlorophyll concentrations were monitored with respect to phylloxera (root-louse) infestation in a Napa Valley (California) vineyard. Study plots were established in areas of severely infested, mildly infested, and uninfested sections of the vineyard. A handheld chlorophyll meter, measuring leaf transmittance of near-infrared and red light, confirmed that reduced foliar chlorophyll concentrations were symptomatic of phylloxera stress in the sample vines. Bidirectional reflectance measurements of green and near-infrared light, taken on fresh leaves with a laboratory spectrophotometer, were related to chlorophyll concentration but did not allow discrimination of mildly infested from uninfested vines.

  14. Transcriptome immunomodulation of in-feed additives in Atlantic salmon Salmo salar infested with sea lice Caligus rogercresseyi.

    PubMed

    Núñez-Acuña, Gustavo; Gonçalves, Ana Teresa; Valenzuela-Muñoz, Valentina; Pino-Marambio, Jorge; Wadsworth, Simon; Gallardo-Escárate, Cristian

    2015-11-01

    One of the most significant threats to the Chilean salmon aquaculture industry is the ectoparasitic sea louse Caligus rogercresseyi. To cope with sea lice infestations, functional diets have become an important component in strengthening the host immune response. The aim of this study was to evaluate molecular mechanisms activated through immunostimulation by in-feed plant-derived additives in Atlantic salmon infected with sea lice. Herein, a transcriptome-wide sequencing analysis was performed from skin and head kidney tissues, evidencing that the immune response genes were the most variable after the challenge, especially in the head kidney, while other genes involved in metabolism were highly expressed individuals fed with the immunostimulants. Interestingly, defensive enzymes such as Cytochrome p450 and serpins were down-regulated in infested individuals, especially in skin tissue. Additionally, MHC-I and MHC-II genes were differentially expressed after the incorporation of the in-feed additives, giving some cues about the protection mechanisms of plant-derived compound as immunostimulants for infested salmons. This is the first published study that evaluates the transcriptomic response of sea lice-infested Atlantic salmon fed with in-feed additives. PMID:26363235

  15. New records of species of Saemundssonia (Insecta: Phthiraptera: Philopteridae) infesting breeding terns in the Arabian Peninsula, with notes on their phylogeny and ecology.

    PubMed

    Shobrak, Mohammed; Alahmed, Azzam; Palma, Ricardo; Almalki, Mohammed; Nasser, Mohamed Gamal El-Den

    2015-07-01

    Six species of terns, which breed on the Arabian Peninsula, were examined for head chewing lice of the genus Saemundssonia in four different islands around the coasts of Saudi Arabia, both in the Red Sea and in the Arabian Gulf. Four louse species were collected: Saemundssonia laticaudata, Saemundssonia melanocephalus, Saemundssonia meridiana and Saemundssonia sternae, of which three are recorded for the first time from this region. Also, we record three new host-louse associations for the world-Saemundssonia laticaudata and Saemundssonia sternae from white-cheeked terns and Saemundssonia melanocephalus from Saunders's terns-including a host-switch event of Saemundssonia laticaudata on white-cheeked terns in the Karan Island population. Gene bank data for the COI gene from seven species of Saemundssonia that infest marine birds were used to propose evolutionary trees using two different statistical methods: maximum parsimony (MP) and neighbour joining (NJ). The result indicated that the tree which was produced by NJ is likely to be more accurate as it appeared more compatible with hosts' phylogeny. The trees indicate relationships between tern Saemundssonia and congeneric species from other marine birds, especially from gulls. An ANOVA was also conducted to test the mean parasite load for each tern species studied, and results indicate that there is a relation between louse loads and colonization behaviour of the hosts. Data from lice examined and illustrations of lice and their hosts are also included. PMID:25924793

  16. 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

  17. Chlorpyrifos for control of the short-nosed cattle louse, Haematopinus eurysternus (Nitzsch) (Anoplura, Haematopinidae) during winter.

    PubMed Central

    Khan, M A; Schaalje, G B

    1985-01-01

    Two groups (A and C) of range cows were treated in February with chlorpyrifos (16 mL Dursban 44/cow) for the control of heavy infestations of the short-nosed cattle louse. Group A was treated in 1977 and group C in 1979 and each treated group was compared with a separate untreated group. Some of the treated cows were identified as carriers of louse infestation (subgroups A1 and C1), while others were noncarriers (subgroups A2 and C2). The maximum level of reduction in louse populations was 99% at week 4 posttreatment in subgroup A1, 99% from weeks 2-16 posttreatment in subgroup A2, 92% at week 3 posttreatment in subgroup C1 and 100% at weeks 15-17 in subgroup C2. Clinically, the treated cows, which were anemic at the time of treatment, recovered from anemia during the posttreatment period of 25 weeks for group A and 17 weeks for group C. Remission of anemia also occurred in the two untreated groups, possibly because of natural summer decline in louse population. The treatment had no effect on the whole blood cholinesterase of the cows and the treated cows showed no signs of organophosphorous toxicity. PMID:2416414

  18. 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

  19. 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

  20. 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

  1. 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…

  2. Pyrethroid tolerance in the chewing louse Bovicola (Werneckiella) ocellatus.

    PubMed

    Ellse, L; Burden, F; Wall, R

    2012-08-13

    Equine pediculosis is a significant health and welfare issue, particularly in elderly and chronically debilitated animals. Currently infestation is controlled predominantly using topically applied pyrethroid insecticides, allowing limited scope for the rotation of drugs and increasing the risk of selection for resistance. Here the insecticidal efficacies of two pyrethroid-based products against the louse Bovicola (Werneckiella) ocellatus collected from donkeys were examined in vitro. The products were cypermethrin (Deosect™, Pfizer Ltd., 5% (w/v) cypermethrin, cutaneous spray) and permethrin (Switch™, VetPlus Ltd., 4% (w/v) permethrin, pour-on). The pyrethroid efficacy was contrasted with that of the organophosphate diazinon, since the louse populations examined were unlikely to have had prior exposure to this compound. The efficacy of diluted pure permethrin, the excipient, butyl dioxitol and the synergist piperonyl butoxide in the presence of the pyrethroids, were also considered. At the concentrations recommended for animal application, neither 4% (w/v) permethrin, nor 0.1% (w/v) cypermethrin had any significant effect on the mortality of B. ocellatus and neither induced significantly more mortality than an acetone-only control. In contrast, 0.04% diazinon caused 70% mortality within 4h and 100% mortality after 24h exposure. The addition of a potential pyrethroid synergist, piperonyl butoxide, in combination with cypermethrin and permethrin, resulted in no significant increase in mortality. It is concluded that the population of lice tested display a high level of pyrethroid tolerance which is likely to reflect the development of resistance. Twenty-four hours after routine treatment of 10 donkeys with a pour-on permethrin product (Switch™, VetPlus Ltd., 4% (w/v) permethrin, pour-on) hair tufts taken from their flanks were not significantly insecticidal compared with hair from the midline application site, implying a low level of insecticide distribution

  3. Laboratory and clinical trials of cocamide diethanolamine lotion against head lice

    PubMed Central

    Brunton, Elizabeth R.; Brown, Christine M.

    2015-01-01

    Context. During the late 1990s, insecticide resistance had rendered a number of treatment products ineffective; some companies saw this as an opportunity to develop alternative types of treatment. We investigated the possibility that a surfactant-based lotion containing 10% cocamide diethanolamine (cocamide DEA) was effective to eliminate head louse infestation. Settings and Design. Initial in vitro testing of the lotion formulation versus laboratory reared body/clothing lice, followed by two randomised, controlled, community-based, assessor blinded, clinical studies. Materials and Methods. Preliminary laboratory tests were performed by exposing lice or louse eggs to the product using a method that mimicked the intended use. Clinical Study 1: Children and adults with confirmed head louse infestation were treated by investigators using a single application of aqueous 10% cocamide DEA lotion applied for 60 min followed by shampooing or a single 1% permethrin creme rinse treatment applied to pre-washed hair for 10 min. Clinical Study 2: Compared two treatment regimens using 10% cocamide DEA lotion that was concentrated by hair drying. A single application left on for 8 h/overnight was compared with two applications 7 days apart of 2 h duration, followed by a shampoo wash. Results. The initial laboratory tests showed a pediculicidal effect for a 60 min application but limited ovicidal effect. A longer application time of 8 h or overnight was found capable of killing all eggs but this differed between batches of test material. Clinical Study 1: Both treatments performed badly with only 3/23 (13%) successful treatments using cocamide DEA and 5/25 (23.8%) using permethrin. Clinical Study 2: The single overnight application of cocamide DEA concentrated by hair drying gave 10/56 (17.9%) successes compared with 19/56 (33.9%) for the 2 h application regimen repeated after 1 week. Intention to treat analysis showed no significant difference (p = 0.0523) between the treatments

  4. Laboratory and clinical trials of cocamide diethanolamine lotion against head lice.

    PubMed

    Burgess, Ian F; Brunton, Elizabeth R; Brown, Christine M

    2015-01-01

    Context. During the late 1990s, insecticide resistance had rendered a number of treatment products ineffective; some companies saw this as an opportunity to develop alternative types of treatment. We investigated the possibility that a surfactant-based lotion containing 10% cocamide diethanolamine (cocamide DEA) was effective to eliminate head louse infestation. Settings and Design. Initial in vitro testing of the lotion formulation versus laboratory reared body/clothing lice, followed by two randomised, controlled, community-based, assessor blinded, clinical studies. Materials and Methods. Preliminary laboratory tests were performed by exposing lice or louse eggs to the product using a method that mimicked the intended use. Clinical Study 1: Children and adults with confirmed head louse infestation were treated by investigators using a single application of aqueous 10% cocamide DEA lotion applied for 60 min followed by shampooing or a single 1% permethrin creme rinse treatment applied to pre-washed hair for 10 min. Clinical Study 2: Compared two treatment regimens using 10% cocamide DEA lotion that was concentrated by hair drying. A single application left on for 8 h/overnight was compared with two applications 7 days apart of 2 h duration, followed by a shampoo wash. Results. The initial laboratory tests showed a pediculicidal effect for a 60 min application but limited ovicidal effect. A longer application time of 8 h or overnight was found capable of killing all eggs but this differed between batches of test material. Clinical Study 1: Both treatments performed badly with only 3/23 (13%) successful treatments using cocamide DEA and 5/25 (23.8%) using permethrin. Clinical Study 2: The single overnight application of cocamide DEA concentrated by hair drying gave 10/56 (17.9%) successes compared with 19/56 (33.9%) for the 2 h application regimen repeated after 1 week. Intention to treat analysis showed no significant difference (p = 0.0523) between the treatments

  5. 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

  6. 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

  7. Delusional Infestation

    PubMed Central

    Laupland, Kevin B.; Valiquette, Louis

    2016-01-01

    Although the practice of infectious diseases involves a broad range of surgical and medical disciplines, interactions with psychiatry are infrequent. Delusional infestation is a condition where an individual has a firmly fixed false belief that they have an infection. Delusional infestation challenges the infectious diseases specialist who must diligently rule out the presence of a true infection. However, perhaps, more importantly, we may need to initiate therapy with neuroleptic medications for which we may have little specific knowledge and experience. In this note we review the diagnosis and management of patients with delusional infestation. PMID:27366186

  8. Can reduced predation offset negative effects of sea louse parasites on chum salmon?

    PubMed

    Peacock, Stephanie J; Connors, Brendan M; Krkosek, Martin; Irvine, James R; Lewis, Mark A

    2014-02-01

    The impact of parasites on hosts is invariably negative when considered in isolation, but may be complex and unexpected in nature. For example, if parasites make hosts less desirable to predators then gains from reduced predation may offset direct costs of being parasitized. We explore these ideas in the context of sea louse infestations on salmon. In Pacific Canada, sea lice can spread from farmed salmon to migrating juvenile wild salmon. Low numbers of sea lice can cause mortality of juvenile pink and chum salmon. For pink salmon, this has resulted in reduced productivity of river populations exposed to salmon farming. However, for chum salmon, we did not find an effect of sea louse infestations on productivity, despite high statistical power. Motivated by this unexpected result, we used a mathematical model to show how a parasite-induced shift in predation pressure from chum salmon to pink salmon could offset negative direct impacts of sea lice on chum salmon. This shift in predation is proposed to occur because predators show an innate preference for pink salmon prey. This preference may be more easily expressed when sea lice compromise juvenile salmon hosts, making them easier to catch. Our results indicate how the ecological context of host-parasite interactions may dampen, or even reverse, the expected impact of parasites on host populations. PMID:24352951

  9. Cutaneous Infections and Infestations

    PubMed Central

    Tomecki, Kenneth J.

    2011-01-01

    Directed and preventive therapies for cutaneous infectious disease and infestation continue to evolve, providing physicians with new options for care. Common infectious diseases (e.g., genital herpes, herpes zoster, and head lice) occur in the outpatient and inpatient setting. This review of the literature highlights new therapies, including those still in development, such as novel drugs and vaccines, all of which should help to decrease the frequency and severity of common infectious diseases of the skin and subcutaneous tissues. PMID:22191004

  10. Honey Bee Colonies Headed by Hyperpolyandrous Queens Have Improved Brood Rearing Efficiency and Lower Infestation Rates of Parasitic Varroa Mites.

    PubMed

    Delaplane, Keith S; Pietravalle, Stéphane; Brown, Mike A; Budge, Giles E

    2015-01-01

    A honey bee queen mates on wing with an average of 12 males and stores their sperm to produce progeny of mixed paternity. The degree of a queen's polyandry is positively associated with measures of her colony's fitness, and observed distributions of mating number are evolutionary optima balancing risks of mating flights against benefits to the colony. Effective mating numbers as high as 40 have been documented, begging the question of the upper bounds of this behavior that can be expected to confer colony benefit. In this study we used instrumental insemination to create three classes of queens with exaggerated range of polyandry--15, 30, or 60 drones. Colonies headed by queens inseminated with 30 or 60 drones produced more brood per bee and had a lower proportion of samples positive for Varroa destructor mites than colonies whose queens were inseminated with 15 drones, suggesting benefits of polyandry at rates higher than those normally obtaining in nature. Our results are consistent with two hypotheses that posit conditions that reward such high expressions of polyandry: (1) a queen may mate with many males in order to promote beneficial non-additive genetic interactions among subfamilies, and (2) a queen may mate with many males in order to capture a large number of rare alleles that regulate resistance to pathogens and parasites in a breeding population. Our results are unique for identifying the highest levels of polyandry yet detected that confer colony-level benefit and for showing a benefit of polyandry in particular toward the parasitic mite V. destructor. PMID:26691845

  11. Honey Bee Colonies Headed by Hyperpolyandrous Queens Have Improved Brood Rearing Efficiency and Lower Infestation Rates of Parasitic Varroa Mites

    PubMed Central

    Delaplane, Keith S.; Pietravalle, Stéphane; Brown, Mike A.; Budge, Giles E.

    2015-01-01

    A honey bee queen mates on wing with an average of 12 males and stores their sperm to produce progeny of mixed paternity. The degree of a queen’s polyandry is positively associated with measures of her colony’s fitness, and observed distributions of mating number are evolutionary optima balancing risks of mating flights against benefits to the colony. Effective mating numbers as high as 40 have been documented, begging the question of the upper bounds of this behavior that can be expected to confer colony benefit. In this study we used instrumental insemination to create three classes of queens with exaggerated range of polyandry– 15, 30, or 60 drones. Colonies headed by queens inseminated with 30 or 60 drones produced more brood per bee and had a lower proportion of samples positive for Varroa destructor mites than colonies whose queens were inseminated with 15 drones, suggesting benefits of polyandry at rates higher than those normally obtaining in nature. Our results are consistent with two hypotheses that posit conditions that reward such high expressions of polyandry: (1) a queen may mate with many males in order to promote beneficial non-additive genetic interactions among subfamilies, and (2) a queen may mate with many males in order to capture a large number of rare alleles that regulate resistance to pathogens and parasites in a breeding population. Our results are unique for identifying the highest levels of polyandry yet detected that confer colony-level benefit and for showing a benefit of polyandry in particular toward the parasitic mite V. destructor. PMID:26691845

  12. 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

  13. 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

  14. 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

  15. Delusional infestation.

    PubMed

    Freudenmann, Roland W; Lepping, Peter

    2009-10-01

    This papers aims at familiarizing psychiatric and nonpsychiatric readers with delusional infestation (DI), also known as delusional parasitosis. It is characterized by the fixed belief of being infested with pathogens against all medical evidence. DI is no single disorder but can occur as a delusional disorder of the somatic type (primary DI) or secondary to numerous other conditions. A set of minimal diagnostic criteria and a classification are provided. Patients with DI pose a truly interdisciplinary problem to the medical system. They avoid psychiatrists and consult dermatologists, microbiologists, or general practitioners but often lose faith in professional medicine. Epidemiology and history suggest that the imaginary pathogens change constantly, while the delusional theme "infestation" is stable and ubiquitous. Patients with self-diagnosed "Morgellons disease" can be seen as a variation of this delusional theme. For clinicians, clinical pathways for efficient diagnostics and etiology-specific treatment are provided. Specialized outpatient clinics in dermatology with a liaison psychiatrist are theoretically best placed to provide care. The most intricate problem is to engage patients in psychiatric therapy. In primary DI, antipsychotics are the treatment of choice, according to limited but sufficient evidence. Pimozide is no longer the treatment of choice for reasons of drug safety. Future research should focus on pathophysiology and the neural basis of DI, as well as on conclusive clinical trials, which are widely lacking. Innovative approaches will be needed, since otherwise patients are unlikely to adhere to any study protocol. PMID:19822895

  16. 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

  17. Delusional Infestation

    PubMed Central

    Freudenmann, Roland W.; Lepping, Peter

    2009-01-01

    Summary: This papers aims at familiarizing psychiatric and nonpsychiatric readers with delusional infestation (DI), also known as delusional parasitosis. It is characterized by the fixed belief of being infested with pathogens against all medical evidence. DI is no single disorder but can occur as a delusional disorder of the somatic type (primary DI) or secondary to numerous other conditions. A set of minimal diagnostic criteria and a classification are provided. Patients with DI pose a truly interdisciplinary problem to the medical system. They avoid psychiatrists and consult dermatologists, microbiologists, or general practitioners but often lose faith in professional medicine. Epidemiology and history suggest that the imaginary pathogens change constantly, while the delusional theme “infestation” is stable and ubiquitous. Patients with self-diagnosed “Morgellons disease” can be seen as a variation of this delusional theme. For clinicians, clinical pathways for efficient diagnostics and etiology-specific treatment are provided. Specialized outpatient clinics in dermatology with a liaison psychiatrist are theoretically best placed to provide care. The most intricate problem is to engage patients in psychiatric therapy. In primary DI, antipsychotics are the treatment of choice, according to limited but sufficient evidence. Pimozide is no longer the treatment of choice for reasons of drug safety. Future research should focus on pathophysiology and the neural basis of DI, as well as on conclusive clinical trials, which are widely lacking. Innovative approaches will be needed, since otherwise patients are unlikely to adhere to any study protocol. PMID:19822895

  18. Phthriasis palpebrarum can resemble tick larva infestation in an eyelid.

    PubMed

    Dağdelen, Serkan; Aykan, Umit; Cetinkaya, Kubilay

    2013-08-01

    The similarities of the larval and nymph stages of the tick and louse (Pthirus pubis) may lead to misdiagnosis in rare cases of infestation of the eyelashes. The most frequent manifestations of tick in the eye are conjunctivitis, uveitis, keratitis, and vasculitis. Tick inoculation of the skin can locally lead to formation of granuloma and abscess. More concerning is the potential systemic sequelae that can result from transmission of zoonoses such as Lyme disease. P. pubis can cause pruritic eyelid margins or unusual blepharoconjunctivitis. We present a case of phthiriasis palpebrarum in a 4-year-old boy. PMID:23993722

  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.

    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

  1. Stress response of Salmo salar (Linnaeus 1758) when heavily infested by Caligus rogercresseyi (Boxshall & Bravo 2000) copepodids.

    PubMed

    González, Margarita P; Vargas-Chacoff, Luis; Marín, Sandra L

    2016-02-01

    The year-round presence of ovigerous females of the parasite Caligus rogercresseyi in the fish farms of southern Chile results in a continuous source of the copepodid (infestive) stage of this louse. The short generation time in spring-summer could lead to high abundances of this copepodid, potentially leading to high infestation levels for fish. Knowing how heavy lice infestations affect Salmo salar can help determine how to time antiparasitic treatments so as to both minimize the treatment impact and reduce lice infestation levels for fish. This study aimed to describe the effects of high infestations of the copepodid stage of C. rogercresseyi on the physiology of S. salar. Two groups of S. salar were used: an infested group (75 copepodids per fish) and a control group (not infested). Sixty-five days after the first infestation, the infested fish group was re-infested at an infestation pressure of 200 copepodids per fish. Sampling was done prior to and following the second infestation, at 56 and 67 days (the latter 2 days following the second infestation). Several physiological variables were measured: cortisol (primary stress response) and glucose, proteins, amino acids, triglycerides, lactate, osmolality levels, and number and diameter of skin mucous cells (secondary stress responses). The plasma cortisol, glucose, and triglyceride levels were altered in the heavily infested fish, as was the diameter of skin mucous cells. These results suggest that heavy infestations of C. rogercresseyi lead to an acute stress response, metabolic reorganization, and increased mucus production in S. salar under heavy infestation conditions. PMID:26394864

  2. The efficacy and safety of alphacypermethrin as a pour-on treatment for water buffalo (Bubalus bubalis) infested with Haematopinus tuberculatus (Phthiraptera: Haematopinidae).

    PubMed

    Veneziano, Vincenzo; Neglia, Gianluca; Cimmino, Roberta; Balestrieri, Anna; Rufrano, Domenico; Bastianetto, Eduardo; Santoro, Mario; Gokbulut, Cengiz

    2013-08-01

    The sucking louse Haematopinus tuberculatus (Burmeister 1839) is an ectoparasite of buffaloes, cattle, camels, and American bison. Alphacypermethrin (ACYP) is a pyrethroid insecticide commonly used to control arthropods of veterinary and public health interest. Therapeutics, such as antiparasitic compounds, is often administered to buffaloes based on dosage and intervals recommended for cattle because very few drugs have buffalo-specific label indications. A trial was conducted on 20 louse-infested buffaloes at a farm to assess the efficacy and safety of ACYP pour-on, at the manufacturer's recommended dose for cattle, on buffaloes naturally infested by H. tuberculatus. Ten animals were assigned to ACYP-treated group (ACYP-group) and ten to untreated control group (C-group). On day 0, all ACYP-group buffaloes received alphacypermethrin pour-on. Louse counts were performed on days -1, 7, 14, 21, 28, 35, 42, 49, and 56 at eight predilection sites on the skin of each buffalo. ACYP was completely effective (100%) at day 7, highly effective (99.8%) at day 14, and completely effective (100%) from day 21 until the end of the study (day 56 post-treatment). During the trial, ACYP was well tolerated by all animals as there were no observed clinically adverse reactions. The results of this trial suggest that ACYP is an effective, safe, and user-friendly compound suitable for treatment of buffaloes with natural louse infestations. PMID:23733232

  3. 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

  4. Phylogenetics and population genetics of the louse fly, Lipoptena mazamae, from Arkansas, USA.

    PubMed

    Trout, R T; Steelman, C D; Szalanski, A L

    2010-09-01

    Louse flies, also known as deer keds (Lipoptena mazamae Rondani), infest cervids such as white-tailed deer, Odocoileus virginianus and vector pathogens such as Anaplasma and Bartonella schoenbuchensis to cattle and humans, respectively. The population genetic structure of 30 L. mazamae collected from white-tailed deer in four regions of Arkansas, U.S.A., designated by county boundaries, was examined using DNA sequences of a 259-bp region of the mitochondrial DNA rRNA 16S gene. Of the 259 nucleotide characters, 33 were variable and 6 haplotypes were identified. Two haplotypes occurred only once (haplotype 3 and 4), whereas two other haplotypes occurred in 43% (haplotype 1 in two regions) and 40% (haplotype 6 in three regions) of the samples. Phylogenetic relationships of the six L. mazamae haplotypes were constructed with other Hippoboscid and Glossinid samples and two clades resulted. Clade 1 was located in the north and western Ozarks whereas clade 2 was found in the northern and eastern Ozarks. Results from the present study indicate that Lipoptena may be a polyphyletic genus; consequently, more research into genetic variation within this genus is necessary. PMID:20534010

  5. Transcriptome mining: Multigene panel to test delousing drug response in the sea louse Caligus rogercresseyi.

    PubMed

    Valenzuela-Muñoz, V; Gallardo-Escárate, C

    2016-02-01

    Controlling infestations of copepodid ectoparasites in the salmon industry is increasingly problematic given higher instances of drug resistance or loss of sensitivity. Despite the importance of this issue, the molecular mechanisms and genes implicated in resistance/susceptibility are only scarcely understood. The objective of the present study was to identify and evaluate the expression levels of candidate genes associated with delousing drug response in the sea louse Caligus rogercresseyi. From RNA-seq data obtained for adult male and female sea lice, 62.48 M reads were assembled in 70,349 high-quality contigs. BLASTX analysis against UniprotKB/Swiss-Prot and the ESTs available for crustaceans in the NCBI database identified 870 transcripts previously related to genes associated with delousing drug response. Furthermore, 14 candidate genes were validated through RT-qPCR and were evaluated with deltamethrin and azamethiphos bioassays. The results evidenced an overregulation of genes involved in ion transport in salmon lice treated with deltamethrin, while those treated with azamethiphos evidenced an overregulation of genes such as cytochrome P450, Carboxylesterase, and acetylcholine receptors. The present study provides a multigene panel to test delousing drug response to pyrethroids and organophosphates in a highly prevalent pathogen of the Chilean salmon industry. PMID:26723558

  6. Acute impacts of the deer ked (Lipoptena cervi) infestation on reindeer (Rangifer tarandus tarandus) behaviour.

    PubMed

    Kynkäänniemi, Sanna-Mari; Kettu, Maria; Kortet, Raine; Härkönen, Laura; Kaitala, Arja; Paakkonen, Tommi; Mustonen, Anne-Mari; Nieminen, Petteri; Härkönen, Sauli; Ylönen, Hannu; Laaksonen, Sauli

    2014-04-01

    Blood-sucking ectoparasites have often a strong impact on the behaviour of their hosts. The annual insect harassment of reindeer (Rangifer tarandus tarandus) has increased in the southern part of the Finnish reindeer herding area because of the recent invasion of a blood-feeding ectoparasitic louse-fly, the deer ked (Lipoptena cervi). We studied the impact of the deer ked on the behaviour of reindeer. Twelve reindeer were infested with a total of 300 keds/reindeer on six occasions in a 5-week period during the deer ked flight season in autumn, while six non-infested reindeer were used as controls. Behavioural patterns indicating potential stress were monitored by visual observation from August to December. The infested reindeer displayed more incidences of restless behaviour than the controls. Shaking and scratching were the most common forms of restless behaviour after infestation of deer keds. Increased grooming was also observed after the transplantation and also later, 1 month after the infestation. Based on the results, the deer ked infestation can cause acute behavioural disturbance in reindeer and, thus, could pose a potential threat to reindeer welfare. Antiparasitic treatment with, e.g. ivermectin, may increase the welfare of parasitized reindeer by reducing deer keds. If the deer ked infestation intensity on the reindeer herding area increases and restless behaviour of reindeer becomes more common, the present results can help in further evaluation of the duration and magnitude of behavioural changes. PMID:24562815

  7. Dispersal of the northern fowl mite, Ornithonyssus sylviarum (Canestrini and Fanzago), and the chicken body louse, Menacanthus stramineus (Nitzsch), among thirty strains of egg-type hens in a caged laying house.

    PubMed

    DeVaney, J A; Quisenberry, J H; Doran, B H; Bradley, J W

    1980-08-01

    From September 1978 through Februrary 1979, dispersal of uncontrolled, naturally occurring populations of the northern fowl mite, Ornithonyssus sylviarum (Canestrini and Fanzago), and the chicken body louse, Menacanthus stramineus (Nitzch) was studied on 30 strains of egg-type pullets reared to 20 weeks old on four growing rations before being housed for egg production. Hens representing all 30 strains and each of the four feeding regimens had mites. The northern fowl mite spread from initial infestations down the entire length of the house in 1 month; after four months, the chicken body louse had spread approximately two-thirds the length of a cage row in the house. Populations of the northern fowl mite increased from very light to extra heavy within 1 month and then began a slow decline. PMID:7413582

  8. 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

  9. 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

  10. Relationships between beak condition, preening behavior and ectoparasite infestation levels in laying hens.

    PubMed

    Vezzoli, Giuseppe; Mullens, Bradley A; Mench, Joy A

    2015-09-01

    The effects of beak condition on ectoparasite populations and preening in laying hens were investigated. Beak-trimmed and beak-intact caged Hy-Line W-36 hens were infested with either chicken body lice or northern fowl mites using a 2×2 factorial design with 4 replicate cages (each containing 2 hens)/treatment: 1) BTL: (beak-trimmed lice-infested); 2) BTM: (beak-trimmed mite-infested); 3) BIL: (beak-intact lice-infested); and 4) BIM: (beak-intact mite-infested). Mite scores and lice numbers were estimated weekly. Hens were video recorded the wk before infestation and at wk 6 and 9 post-infestation. Time spent preening on 6 body areas and in total were analyzed using a repeated measures ANOVA. There was a wk×beak condition interaction for lice loads, with BTL harboring approximately 17 times more lice than BIL from wk 7 to 10 post-infestation (P<0.0001). Beak condition affected mite loads (P<0.0001), with BTM having a higher mite score (3.8±0.26) than BIM (1.4±0.26). At peak infestation, BTL spent more total time preening (P=0.02, s±SE: 232.1±37.6) than prior to infestation (33.9±37.6) and directed their preening behavior towards the vent. In contrast, BIL (73.9±37.6), BTM (9.4±1.6), and BIM (8.6±1.6) did not increase total time spent preening over pre-infestation levels (103.6±37.6, 5.8±1.6, 6.7±1.6 respectively), although BTM did redirect their preening behavior toward the vent. This study confirmed previous studies showing that an intact beak is important for reducing ectoparasite infestations. Preening behavior increased in response to lice infestation, but only in beak-trimmed hens; preening behavior and louse load were correlated at peak infestation. In contrast, mite infestation did not lead to increased preening, and there was no correlation between preening and mite load. However, both lice- and mite-infested hens directed preening behavior predominantly towards the vent where these parasites are typically found. PMID:26155987

  11. Utilization of the human louse genome to study insecticide resistance and innate immune response

    PubMed Central

    Clark, J. Marshall; Yoon, Kyong Sup; Kim, Ju Hyeon; Lee, Si Hyeock; Pittendrigh, Barry R.

    2015-01-01

    Since sequencing the human body louse genome, substantial advances have occurred in the utilization of the information gathered from louse genomes and transcriptomes. Comparatively, the body louse genome contains far fewer genes involved in environmental response, such as xenobiotic detoxification and innate immune response. Additionally, the body louse maintains a primary bacterial endosymbiont, Candidatus Riesia pediculicola, and a number of bacterial pathogens that it vectors, which have genomes that are also reduced in size. Thus, human louse genomes offer unique information and tools for use in advancing our understanding of coevolution among vectors, endosymbionts and pathogens. In this review, we summarize the current literature on the extent of pediculicide resistance, the availability of new pediculicides and information establishing this organism as an efficient model to study how xenobiotic metabolism, which is involved in insecticide resistance, is induced and how insects modify their innate immune response upon bacterial challenge resulting in enhanced vector competence. PMID:25987230

  12. RNA-Seq Analysis Using De Novo Transcriptome Assembly as a Reference for the Salmon Louse Caligus rogercresseyi

    PubMed Central

    Gallardo-Escárate, Cristian; Valenzuela-Muñoz, Valentina; Nuñez-Acuña, Gustavo

    2014-01-01

    Despite the economic and environmental impacts that sea lice infestations have on salmon farming worldwide, genomic data generated by high-throughput transcriptome sequencing for different developmental stages, sexes, and strains of sea lice is still limited or unknown. In this study, RNA-seq analysis was performed using de novo transcriptome assembly as a reference for evidenced transcriptional changes from six developmental stages of the salmon louse Caligus rogercresseyi. EST-datasets were generated from the nauplius I, nauplius II, copepodid and chalimus stages and from female and male adults using MiSeq Illumina sequencing. A total of 151,788,682 transcripts were yielded, which were assembled into 83,444 high quality contigs and subsequently annotated into roughly 24,000 genes based on known proteins. To identify differential transcription patterns among salmon louse stages, cluster analyses were performed using normalized gene expression values. Herein, four clusters were differentially expressed between nauplius I–II and copepodid stages (604 transcripts), five clusters between copepodid and chalimus stages (2,426 transcripts), and six clusters between female and male adults (2,478 transcripts). Gene ontology analysis revealed that the nauplius I–II, copepodid and chalimus stages are mainly annotated to aminoacid transfer/repair/breakdown, metabolism, molting cycle, and nervous system development. Additionally, genes showing differential transcription in female and male adults were highly related to cytoskeletal and contractile elements, reproduction, cell development, morphogenesis, and transcription-translation processes. The data presented in this study provides the most comprehensive transcriptome resource available for C. rogercresseyi, which should be used for future genomic studies linked to host-parasite interactions. PMID:24691066

  13. Gene expression in five salmon louse (Lepeophtheirus salmonis, Krøyer 1837) tissues.

    PubMed

    Edvardsen, Rolf Brudvik; Dalvin, Sussie; Furmanek, Tomasz; Malde, Ketil; Mæhle, Stig; Kvamme, Bjørn Olav; Skern-Mauritzen, Rasmus

    2014-12-01

    The Atlantic salmon, Salmo salar L, is an important species both for traditional fishery and fish farming. Many Atlantic salmon stocks have been declining and a suspected main contributor to this decline is the salmon louse (Lepeophtheirus salmonis); a parasitic copepod living off the salmonid hosts epidermal tissues and blood. Contributing to the growing body of knowledge on the molecular biology of the salmon louse we have utilized a microarray containing 11,100 salmon louse genes to study the gene expression patterns in selected tissues. This approach has yielded information about potential functions of the transcripts and tissues. Microarray analyses were preformed on subcuticular and frontal (neuronal and gland enriched tissue) tissues, as well as gut, ovary and testes of adult lice. Tissue specific transcriptomes were evident, allowing us to address main traits of functional partitioning between tissues and providing valuable insight into the biology of the louse. The results furthermore represent an important tool and resource for further experiments. PMID:24999079

  14. [Occurrence of head pediculosis and its control in children's homes in selected provinces of Poland in the years 2007-2009].

    PubMed

    Sawicka, Bozena; Mikulak, Ewa; Gliniewicz, Aleksandra

    2011-01-01

    Despite civilisation development and the easy access to pediculicides, head pediculosis remains still the social, hygienic and medical problem. In the years 2007 - 2009 in children's homes in selected provinces of Poland the questionnaire survey on the occurrence of head pediculosis and its control have been conducted. From 127 orphanages 61 (48.03%) sent back fulfilled questionnaire. The infestation level ranged from 4.63% (Swietokrzyskie Province, 2009) until 17.63% (Mazowieckie Province 2007) in the surveyed children's homes. The most head pediculosis cases were observed among girls 6 - 12 years old in children's homes from all regions investigated. The profile of pediculicides used had been changed during our study: in the first year the most often pediculicides with the insecticide permethrin were used. In the next years their use decreased, but the use of herbal and silicone pediculicides increased. The efficacy of anti-louse product was the most important factor for the respondents when they choose an pediculicide. PMID:22390057

  15. Lousy mums: patterns of vertical transmission of an amphibious louse.

    PubMed

    Leonardi, M S; Crespo, E A; Raga, J A; Aznar, F J

    2013-09-01

    In this study, we document patterns of vertical transmission of the amphibious louse Antarctophthirus microchir (Echinophthiriidae) in pups of South American sea lion, Otaria flavescens, from Patagonia. Vertical transmission is fundamental for the long-term stability of A. microchir populations because only pups stay long enough (1 month) on land for the louse to reproduce. A total of 72 pups ≤7 days old from a single rookery were captured and examined for lice. Infection parameters and population structure of A. microchir did not differ among pups collected at the beginning, middle, and end of the reproductive season, suggesting that patterns of early vertical transmission are not affected by the increase of rookery size during this period. Over 60% of 1-day-old pups were infected with A. microchir, and recruitment increased in pups up to 3 days old and then leveled off. In 1-day-old pups, significantly more adults than nymphs were found, but the pattern was reversed in older pups. The number of first-stage nymphs was significantly smaller than that of second- and third-stage nymphs, as it was the number of males vs. females, particularly in 1-day-old pups. Three non-exclusive hypotheses could account for these patterns, i.e., recruitment merely reflects the population structure of A. microchir is cows; the relative ability of lice to pass from cows onto pups increases in advanced instars; and/or natural selection favors transmission of adults, especially females, because they accrue greater fitness. The importance of latter hypothesis should not be underestimated in a species with a tight reproductive schedule. PMID:23828192

  16. Aquaporin family genes exhibit developmentally-regulated and host-dependent transcription patterns in the sea louse Caligus rogercresseyi.

    PubMed

    Farlora, Rodolfo; Valenzuela-Muñoz, Valentina; Chávez-Mardones, Jacqueline; Gallardo-Escárate, Cristian

    2016-07-01

    Aquaporins are small integral membrane proteins that function as pore channels for the transport of water and other small solutes across the cell membrane. Considering the important roles of these proteins in several biological processes, including host-parasite interactions, there has been increased research on aquaporin proteins recently. The present study expands on the knowledge of aquaporin family genes in parasitic copepods, examining diversity and expression during the ontogeny of the sea louse Caligus rogercresseyi. Furthermore, aquaporin expression was evaluated during the early infestation of Atlantic (Salmo salar) and Coho salmon (Oncorhynchus kisutch). Deep transcriptome sequencing data revealed eight full length and two partial open reading frames belonging to the aquaporin protein family. Clustering analyses with identified Caligidae sequences revealed three major clades of aquaglyceroporins (Cr-Glp), classical aquaporin channels (Cr-Bib and Cr-PripL), and unorthodox aquaporins (Cr-Aqp12-like). In silico analysis revealed differential expression of aquaporin genes between developmental stages and between sexes. Male-biased expression of Cr-Glp1_v1 and female-biased expression of Cr-Bib were further confirmed in adults by RT-qPCR. Additionally, gene expressions were measured for seven aquaporins during the early infestation stage. The majority of aquaporin genes showed significant differential transcription expressions between sea lice parasitizing different hosts, with Atlantic salmon sea lice exhibiting overall reduced expression as compared to Coho salmon. The observed differences in the regulation of aquaporin genes may reveal osmoregulatory adaptations associated with nutrient ingestion and metabolite waste export, exposing complex host-parasite relationships in C. rogercresseyi. PMID:27016299

  17. Immune adaptive response induced by Bicotylophora trachinoti (Monogenea: Diclidophoridae) infestation in pompano Trachinotus marginatus (Perciformes: Carangidae).

    PubMed

    Chaves, I S; Luvizzotto-Santos, R; Sampaio, L A N; Bianchini, A; Martínez, P E

    2006-09-01

    Fish have developed protective strategies against monogeneans through immunological responses. In this study, immune adaptive response to parasites was analysed in the pompano Trachinotus marginatus infested by Bicotylophora trachinoti. Hosts were pre-treated with formalin and after 10 days assigned to one of the following experimental treatments: (1) fish infested with remaining eggs of B. trachinoti; (2) fish infested with remaining eggs of B. trachinoti and experimentally re-infested by exposure to T. marginatus heavily infested with B. trachinoti. Samples were collected at 0, 15, and 30 days. Gills were dissected to check the presence of B. trachinoti. Blood was collected for haematological and biochemical assays. Spleen and head-kidney were dissected for phagocytosis assay. The spleen-somatic index was also calculated. Re-infested fish showed a faster and higher parasite infestation than infested ones. The parasite mean abundance at 15 days was 24.86+/-13.32 and 11.67+/-8.57 for re-infested and infested fish, respectively. In both groups, hosts showed an immune adaptive response to parasite infestation that was marked by an increased number of leukocytes. Also, phagocytosis (%) in spleen and head-kidney cells was stimulated after parasite infestation (92.50+/-3.73 and 66.00+/-9.54, respectively), becoming later depressed (77.39+/-6.69 and 53.23+/-9.14, respectively). These results support the hypothesis that monogenean infestation induces a biphasic response of the non-specific defence mechanisms in the pompano T. marginatus. This response is marked by an initial stimulation followed by a later depression of the non-specific defence mechanisms. PMID:16483796

  18. FUSARIUM SPECIES SYNTHESIZE ALKALINE PROTEINASES IN INFESTED BARLEY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Barley (Hordeum vulgare L.) that is infested with Fusarium head blight (FHB, `scab') is unsuitable for malting and brewing because it may contain mycotoxins and has unacceptable malting quality. Fungal proteinases are apparently involved in plant-microbe interactions, because they degrade the storag...

  19. Mixture toxicity effects of sea louse control agents in Daphnia magna.

    PubMed

    Rose, Stephanie; Altenburger, Rolf; Sturm, Armin

    2016-02-01

    Caligid sea lice are ectoparasites causing major disease problems in industrial salmon farming. Sea louse control currently relies widely on parasiticides. Among non-target species, crustaceans are particularly susceptible to salmon delousing agents. Drug combinations have recently been suggested for sea louse control; however, no information is available on the non-target effects of such mixtures. To obtain first insights into combination effects of salmon parasiticides, acute toxicity tests with the crustacean model species Daphnia magna were conducted. Four compounds, including two organophosphates and two pyrethroids, were tested individually and in all pair-wise combinations at one fixed concentration ratio. For most combinations, observed toxicities were close to predictions assuming concentration additivity. However, deltamethrin and cypermethrin showed greater than predicted combination effects, while the inverse was observed for deltamethrin and malathion. The results demonstrate combination effects of anti-sea louse agents and suggest that predictions based on concentration additivity are in most cases protective. PMID:26401637

  20. Genome sequences of the human body louse and its primary endosymbiont provide insights into the permanent parasitic lifestyle

    PubMed Central

    Kirkness, Ewen F.; Haas, Brian J.; Sun, Weilin; Braig, Henk R.; Perotti, M. Alejandra; Clark, John M.; Lee, Si Hyeock; Robertson, Hugh M.; Kennedy, Ryan C.; Elhaik, Eran; Gerlach, Daniel; Kriventseva, Evgenia V.; Elsik, Christine G.; Graur, Dan; Hill, Catherine A.; Veenstra, Jan A.; Walenz, Brian; Tubío, José Manuel C.; Ribeiro, José M. C.; Rozas, Julio; Johnston, J. Spencer; Reese, Justin T.; Popadic, Aleksandar; Tojo, Marta; Raoult, Didier; Reed, David L.; Tomoyasu, Yoshinori; Kraus, Emily; Mittapalli, Omprakash; Margam, Venu M.; Li, Hong-Mei; Meyer, Jason M.; Johnson, Reed M.; Romero-Severson, Jeanne; VanZee, Janice Pagel; Alvarez-Ponce, David; Vieira, Filipe G.; Aguadé, Montserrat; Guirao-Rico, Sara; Anzola, Juan M.; Yoon, Kyong S.; Strycharz, Joseph P.; Unger, Maria F.; Christley, Scott; Lobo, Neil F.; Seufferheld, Manfredo J.; Wang, NaiKuan; Dasch, Gregory A.; Struchiner, Claudio J.; Madey, Greg; Hannick, Linda I.; Bidwell, Shelby; Joardar, Vinita; Caler, Elisabet; Shao, Renfu; Barker, Stephen C.; Cameron, Stephen; Bruggner, Robert V.; Regier, Allison; Johnson, Justin; Viswanathan, Lakshmi; Utterback, Terry R.; Sutton, Granger G.; Lawson, Daniel; Waterhouse, Robert M.; Venter, J. Craig; Strausberg, Robert L.; Collins, Frank H.; Zdobnov, Evgeny M.; Pittendrigh, Barry R.

    2010-01-01

    As an obligatory parasite of humans, the body louse (Pediculus humanus humanus) is an important vector for human diseases, including epidemic typhus, relapsing fever, and trench fever. Here, we present genome sequences of the body louse and its primary bacterial endosymbiont Candidatus Riesia pediculicola. The body louse has the smallest known insect genome, spanning 108 Mb. Despite its status as an obligate parasite, it retains a remarkably complete basal insect repertoire of 10,773 protein-coding genes and 57 microRNAs. Representing hemimetabolous insects, the genome of the body louse thus provides a reference for studies of holometabolous insects. Compared with other insect genomes, the body louse genome contains significantly fewer genes associated with environmental sensing and response, including odorant and gustatory receptors and detoxifying enzymes. The unique architecture of the 18 minicircular mitochondrial chromosomes of the body louse may be linked to the loss of the gene encoding the mitochondrial single-stranded DNA binding protein. The genome of the obligatory louse endosymbiont Candidatus Riesia pediculicola encodes less than 600 genes on a short, linear chromosome and a circular plasmid. The plasmid harbors a unique arrangement of genes required for the synthesis of pantothenate, an essential vitamin deficient in the louse diet. The human body louse, its primary endosymbiont, and the bacterial pathogens that it vectors all possess genomes reduced in size compared with their free-living close relatives. Thus, the body louse genome project offers unique information and tools to use in advancing understanding of coevolution among vectors, symbionts, and pathogens. PMID:20566863

  1. Uncovering deep mysteries: the underwater life of an amphibious louse.

    PubMed

    Leonardi, Maria Soledad; Aznar, F Javier; Crespo, Enrique A; Lazzari, Claudio R

    2014-12-01

    Despite the incredible success of insects in colonizing almost every habitat, they remain virtually absent in one major environment--the open sea. A variety of hypotheses have been raised to explain why just a few insect species are present in the ocean, but none of them appears to be fully explanatory. Lice belonging to the family Echinophthiriidae are ectoparasites on different species of pinnipeds and river otters, i.e. they have amphibious hosts, who regularly perform long excursions into the open sea reaching depths of hundreds of meters (thousands of feets). Consequently, lice must be able to support not only changes in their surrounding media, but also extreme variations in hydrostatic pressure as well as breathing in a low oxygen atmosphere. In order to shed some light on the way lice can survive during the diving excursions of their hosts, we have performed a series of experiments to test the survival capability of different instars of Antarctophthirus microchir (Phthiraptera: Anoplura) from South American sea lions Otaria flavescens, when submerged into seawater. These experiments were aimed at analyzing: (a) immersion tolerance along the louse life; (b) lice's ability to obtain oxygen from seawater; (c) physiological responses and mechanisms involved in survival underwater. Our experiments showed that the forms present in non-diving pups--i.e. eggs and first-instar nymphs--were unable to tolerate immersion in water, while following instars and adults, all usually found in diving hosts, supported it very well. Furthermore, as long as the level of oxygen dissolved in water was higher, the lice survival capability underwater increased, and the recovery period after returning to air declined. These results are discussed in relation to host ecology, host exploitation and lice functional morphology. PMID:25449903

  2. Identification and Functional Expression of a Glutamate- and Avermectin-Gated Chloride Channel from Caligus rogercresseyi, a Southern Hemisphere Sea Louse Affecting Farmed Fish

    PubMed Central

    Niemeyer, María Isabel; Marabolí, Vanessa; González-Nilo, F. Danilo; Teulon, Jacques; Sepúlveda, Francisco V.; Cid, L. Pablo

    2014-01-01

    Parasitic sea lice represent a major sanitary threat to marine salmonid aquaculture, an industry accounting for 7% of world fish production. Caligus rogercresseyi is the principal sea louse species infesting farmed salmon and trout in the southern hemisphere. Most effective control of Caligus has been obtained with macrocyclic lactones (MLs) ivermectin and emamectin. These drugs target glutamate-gated chloride channels (GluCl) and act as irreversible non-competitive agonists causing neuronal inhibition, paralysis and death of the parasite. Here we report the cloning of a full-length CrGluClα receptor from Caligus rogercresseyi. Expression in Xenopus oocytes and electrophysiological assays show that CrGluClα is activated by glutamate and mediates chloride currents blocked by the ligand-gated anion channel inhibitor picrotoxin. Both ivermectin and emamectin activate CrGluClα in the absence of glutamate. The effects are irreversible and occur with an EC50 value of around 200 nM, being cooperative (nH = 2) for ivermectin but not for emamectin. Using the three-dimensional structure of a GluClα from Caenorabditis elegans, the only available for any eukaryotic ligand-gated anion channel, we have constructed a homology model for CrGluClα. Docking and molecular dynamics calculations reveal the way in which ivermectin and emamectin interact with CrGluClα. Both drugs intercalate between transmembrane domains M1 and M3 of neighbouring subunits of a pentameric structure. The structure displays three H-bonds involved in this interaction, but despite similarity in structure only of two these are conserved from the C. elegans crystal binding site. Our data strongly suggest that CrGluClα is an important target for avermectins used in the treatment of sea louse infestation in farmed salmonids and open the way for ascertaining a possible mechanism of increasing resistance to MLs in aquaculture industry. Molecular modeling could help in the design of new, more efficient

  3. 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

  4. Louse-borne relapsing fever in a refugee from Somalia arriving in Belgium.

    PubMed

    Darcis, Gilles; Hayette, Marie-Pierre; Bontems, Sebastien; Sauvage, Anne-Sophie; Meuris, Christelle; Van Esbroeck, Marjan; Leonard, Philippe

    2016-03-01

    We report a case of louse-borne relapsing fever (LBRF) in a refugee from Somalia who had arrived in Belgium a few days earlier. He complained of myalgia and secondarily presented fever. Blood smears revealed spirochetes later identified as Borrelia recurrentis. LBRF should be considered in countries hosting refugees, particularly those who transit through endemic regions. PMID:27356309

  5. Comparative in vitro tests on the efficacy and safety of 13 anti-head-lice products.

    PubMed

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

    2010-01-01

    Head lice are an emerging social problem, not only in economically poor countries but also in practically all other societies. Several of the common anti-louse products have lost--at least in part--their efficacy due to increasing resistance of lice against insecticides such as permethrin or allethrin. Other compounds, like lindan, were redrawn or banned due to high toxicity. Some recently developed products are based on dimethicones or cyclomethicones and turned out to be easily inflammable. Other styled medicinal products are based on plant extracts-some were proven of high efficacy-others of ineffectivity. The present study investigated in in vitro tests the anti-head louse efficacy of 13 products, the contents of which are used worldwide: Aesculo-Gel L, EtoPril, Goldgeist Forte, InfectoPedicul, Jacutin Pedicul Fluid, K.Laus, Liberalice, Licatack, Mosquito Läuse-Shampoo, Nyda, Paranix, Picksan Louse Stop, and Wash Away Louse. It turned out that several of them are easily inflammable, and therefore, they endanger users (InfectoPedicul, Paranix, EtoPril, Nyda, Goldgeist Forte, and K.Laus, see Table 1). Others have to remain for many hours on the hair in order to reach efficacy (Table 4). During such long periods, highly dosed oils may become inhaled and thus may become dangerous for the user's lung epithelia by covering them. When incubating the lice for 3 or 10 min in vitro, only the following products killed all lice exposed to these products: InfectoPedicul, Paranix, Jacutin Pedicul Fluid, Nyda, K.Laus, Picksan Louse Stop, Licatack, and Wash Away Louse. When evaluating the possible dangers for the users, the last three products, especially, derived from plant extracts, are safe and highly effective at the same time. Furthermore, they had been tested dermatologically as "very good". PMID:19908068

  6. 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 ...

  7. 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

  8. 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

  9. Detailed surface morphology of the 'lobster louse' copepod, Nicothoë astaci, a haematophagous gill parasite of the European lobster, Homarus gammarus.

    PubMed

    Davies, Charlotte E; Thomas, Gethin R; Maffeis, Thierry G G; Wootton, Emma C; Penny, Mark W; Rowley, Andrew F

    2014-10-01

    The ectoparasitic copepod, Nicothoë astaci (the 'lobster louse'), infests the gills of the European lobster, Homarus gammarus. There have been limited studies on this haematophagous species; therefore knowledge of this parasite is rudimentary. The current study examines the surface morphology of this parasitic copepod, detached from the host, concentrating on adaptations of the suctorial mouthpart, the oral disc. Cryo-scanning electron microscopy revealed structural adaptations that facilitate attachment of these parasites to the gill filaments of their lobster host. The aperture of the feeding channel, through which host haemolymph is drawn, is only ca. 5μm in diameter. The edge of the oral disc is lined with numerous setae, whilst the surface of the disc is covered with large numbers of small (<1μm in diameter) teeth-like structures, which presumably pierce through, and grip, the cuticle lining of the host's gill. Overall, these structures are thought to provide a 'vacuum seal' to assist in pumping of blood, via peristalsis, into the alimentary canal of the copepod host. PMID:25196471

  10. Insects and Spiders: Infestations and Bites

    PubMed Central

    Turgeon, E.W.T.

    1987-01-01

    Despite successful eradication techniques and specific effective therapies, insect bites and infestations remain a source of great human misery. The current scabies pandemic shows no signs of abating. Bed bugs, which through the ages have been second only to the malarial mosquito as an insect vector of fatal infection, have now been implicated in the transmission of Hepatitis B and possibly African acquired immune deficiency syndrome (AIDS). The incidence of head- and pubic lice is on the rise, the latter paralleling, and often co-existing with, other sexually transmitted diseases. Black widow spiders are native to many populous areas in southern Canada, and the brown recluse spider's range now encompasses Canada, thanks to moving vans and central heating. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6 PMID:21263961

  11. 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

  12. Eight polymorphic microsatellite markers isolated from the widespread avian louse Colpocephalum turbinatum (Phthiraptera: Amblycera: Menoponidae).

    PubMed

    Peters, Maureen B; Whiteman, Noah K; Hagen, Cris; Parker, Patricia G; Glenn, Travis C

    2009-05-01

    We report eight novel microsatellite loci for Colpocephalum turbinatum, a parasitic louse of the endangered Galápagos hawk (Buteo galapagoensis). Two island populations of C. turbinatum (N = 30) were genotyped for each locus. We found between two and 12 alleles per locus, polymorphic information content from 0.268 to 0.798, observed heterozygosity from 0.067 to 0.667 and no linkage disequilibrium was detected between loci. These markers will be useful in understanding contemporary gene flow of C. turbinatum among islands in the Galápagos and in understanding transmission dynamics between B. galapagoensis hosts, within and between social groups. Because this louse is unusually widespread among avian host taxa, parasitizing at least 53 bird species in the Falconiformes, Strigiformes and Columbiformes, these markers are likely to be useful outside the context of the Galápagos Islands. PMID:21564787

  13. Molecular characterization and knock-down of salmon louse (Lepeophtheirus salmonis) prostaglandin E synthase.

    PubMed

    Eichner, Christiane; Øvergård, Aina-Cathrine; Nilsen, Frank; Dalvin, Sussie

    2015-12-01

    The salmon louse (Lepeophtheirus salmonis) is a major parasite of salmonid fish in the marine environment. The interaction between the parasite and the host upon infection is not completely understood. However, it is clear that the parasite influences the host and its immune system. Prostaglandins produced by parasites such as flatworms, roundworms and ticks are documented or assumed to play a role in immunomodulation of the host. In the salmon louse, the effect of prostaglandins on the host is assumed, but remains to be documented. In this study, a salmon louse prostaglandin E2 synthase (LsPGES2) is characterized. Ontogenetic analysis showed that LsPGES2 is relatively stable expressed during development. The highest level of expression was seen in the free living stages, although elevated levels of LsPGES2 were also found in adult females. In copepodids, LsPGES2 is found around muscle cells, while it is observed in the reproductive organs of adult female lice. LsPGES2 expression was knocked-down by RNA interference in nauplii, but emerging copepodids did not display any changes in morphology nor ability to infect and develop to adult stages on fish. Additional knock-down of LsPGES2 in adult female lice did not produce any characteristic changes in phenotype nor reproductive output. It is concluded that under these experimental conditions, knock-down of LsPGES2 did not affect any essential functions of the salmon louse, neither in the free-living nor the parasitic stages. PMID:26348267

  14. Louse-borne relapsing fever (Borrelia recurrentis) in asylum seekers from Eritrea, the Netherlands, July 2015.

    PubMed

    Wilting, K R; Stienstra, Y; Sinha, B; Braks, M; Cornish, D; Grundmann, H

    2015-01-01

    Two patients from Eritrea, recently arrived in the Netherlands, presented with fever and were investigated for malaria. Bloodfilms showed spirochetes but no blood parasites. Louse-borne relapsing fever caused by Borrelia recurrentis was diagnosed. Treatment was complicated by severe Jarisch-Herxheimer reactions in both patients. Physicians should be aware of the possibility of B. recurrentis infection in migrant populations who travel under crowded conditions, especially after passing through endemic areas such as Ethiopia and neighbouring countries. PMID:26250069

  15. Life history parameters of the cattle long-nosed sucking louse, Linognathus vituli.

    PubMed

    Colwell, D D

    2014-12-01

    Cattle sucking lice, Linognathus vituli (L.) (Phthiraptera: Linognathidae), were obtained from naturally infected cattle and maintained within 'arenas' affixed to the backs of cattle confined in controlled environment chambers maintained at a constant temperature of 15 °C. Temperatures measured within the arenas at an ambient temperature of 15 °C were constant at about 34 °C and only slightly above the temperature on nearby skin. The effect of temperature on egg development was determined using a gradient of temperatures between 25 °C and 41 °C. Eggs did not develop at temperatures of < 26 °C or > 39 °C. Survival of eggs was highest at temperatures of 30 °C and 35 °C. The earliest hatch was observed at 5 days post-oviposition (at 33-35 °C). Development was extended to as long as 13 days at the lower temperatures. Kaplan-Meier survival probabilities were compared for lice kept at two densities in the arenas and showed there to be no effect of density on louse survival. Similarly, the mean number of eggs/louse/day over an 8-day period was not influenced by louse density. PMID:24890771

  16. SUPPLEMENTING NATIVE SUGARCANE BORER INFESTATIONS BY ARTIFICIAL INFESTATION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    When conducting assessments of the response of sugarcane varieties to feeding by the sugarcane borer (Diatraea saccharalis), we routinely intercrop sugarcane (interspecific hybrids of Saccharum spp.) rows with a row of corn (Zea mays) and infest these corn plants with laboratory reared, first-instar...

  17. Characterization of 17 novel polymorphic microsatellite loci in the mammal chewing louse Geomydoecus ewingi (Insecta: Phthiraptera) for population genetic analyses.

    PubMed

    Nessner, C E; Andersen, J J; Renshaw, M A; Giresi, M M; Light, J E

    2014-12-01

    We report 17 novel microsatellite loci in the parasitic chewing louse Geomydoecus ewingi, a common parasite of the pocket gopher, Geomys breviceps . Thirty-three G. ewingi individuals from 1 geographic locality and 3 pocket gopher hosts (populations) were genotyped at each locus. The number of alleles per locus ranged from 3 to 13. Observed heterozygosity ranged from 0.182 to 0.788. Four to 6 loci per louse population fell outside of Hardy-Weinberg expectations (HWE) and examination of population structure also revealed substantial homozygote excess as well as significant structure among louse populations. These findings are likely the consequence of biological characteristics of the lice (low dispersal abilities, population bottlenecks, etc.), which can result in inbreeding. Notably, when all louse individuals were analyzed together as 1 population, a Wahlund effect was detected, supporting that louse populations are restricted to 1 host individual. The microsatellite markers characterized in this study will be useful in future studies exploring the population dynamics in host-parasite systems, potentially yielding a better understanding of the processes underlying symbiotic associations. PMID:24992004

  18. Suicide following an infestation of bed bugs

    PubMed Central

    Burrows, Stephanie; Perron, Stéphane; Susser, Stephanie

    2013-01-01

    Patient: Male, 62 Final Diagnosis: Bipolar disorder Symptoms: Bordeline personality disorder Medication: — Clinical Procedure: Bed bug infestation Specialty: Psychiatry Objective: Unusual clinical course Background: In the past decade, bed bug infestations have been increasingly common in high income countries. Psychological consequences of these infestations are rarely examined in the scientific literature. Case Report: We present a case, based on a coroner’s investigation report, of a woman with previous psychiatric morbidity who jumped to her death following repeated bed bug infestations in her apartment. Our case report shows that the bed bug infestations were the likely trigger for the onset a negative psychological state that ultimately led to suicide. Conclusions: Given the recent surge in infestations, rapid action needs to be taken not only in an attempt to control and eradicate the bed bugs but also to adequately care for those infested by bed bugs. PMID:23826461

  19. Identification of a Sex-Linked SNP Marker in the Salmon Louse (Lepeophtheirus salmonis) Using RAD Sequencing

    PubMed Central

    Taggart, John B.; Christie, Hayden R. L.; Bassett, David I.; Bron, James E.; Skuce, Philip J.; Gharbi, Karim; Skern-Mauritzen, Rasmus; Sturm, Armin

    2013-01-01

    The salmon louse (Lepeophtheirus salmonis (Krøyer, 1837)) is a parasitic copepod that can, if untreated, cause considerable damage to Atlantic salmon (Salmo salar Linnaeus, 1758) and incurs significant costs to the Atlantic salmon mariculture industry. Salmon lice are gonochoristic and normally show sex ratios close to 1:1. While this observation suggests that sex determination in salmon lice is genetic, with only minor environmental influences, the mechanism of sex determination in the salmon louse is unknown. This paper describes the identification of a sex-linked Single Nucleotide Polymorphism (SNP) marker, providing the first evidence for a genetic mechanism of sex determination in the salmon louse. Restriction site-associated DNA sequencing (RAD-seq) was used to isolate SNP markers in a laboratory-maintained salmon louse strain. A total of 85 million raw Illumina 100 base paired-end reads produced 281,838 unique RAD-tags across 24 unrelated individuals. RAD marker Lsa101901 showed complete association with phenotypic sex for all individuals analysed, being heterozygous in females and homozygous in males. Using an allele-specific PCR assay for genotyping, this SNP association pattern was further confirmed for three unrelated salmon louse strains, displaying complete association with phenotypic sex in a total of 96 genotyped individuals. The marker Lsa101901 was located in the coding region of the prohibitin-2 gene, which showed a sex-dependent differential expression, with mRNA levels determined by RT-qPCR about 1.8-fold higher in adult female than adult male salmon lice. This study’s observations of a novel sex-linked SNP marker are consistent with sex determination in the salmon louse being genetic and following a female heterozygous system. Marker Lsa101901 provides a tool to determine the genetic sex of salmon lice, and could be useful in the development of control strategies. PMID:24147087

  20. Two Bacterial Genera, Sodalis and Rickettsia, Associated with the Seal Louse Proechinophthirus fluctus (Phthiraptera: Anoplura)

    PubMed Central

    Allen, Julie M.; Koga, Ryuichi; Fukatsu, Takema; Sweet, Andrew D.; Johnson, Kevin P.; Reed, David L.

    2016-01-01

    ABSTRACT Roughly 10% to 15% of insect species host heritable symbiotic bacteria known as endosymbionts. The lice parasitizing mammals rely on endosymbionts to provide essential vitamins absent in their blood meals. Here, we describe two bacterial associates from a louse, Proechinophthirus fluctus, which is an obligate ectoparasite of a marine mammal. One of these is a heritable endosymbiont that is not closely related to endosymbionts of other mammalian lice. Rather, it is more closely related to endosymbionts of the genus Sodalis associated with spittlebugs and feather-chewing bird lice. Localization and vertical transmission of this endosymbiont are also more similar to those of bird lice than to those of other mammalian lice. The endosymbiont genome appears to be degrading in symbiosis; however, it is considerably larger than the genomes of other mammalian louse endosymbionts. These patterns suggest the possibility that this Sodalis endosymbiont might be recently acquired, replacing a now-extinct, ancient endosymbiont. From the same lice, we also identified an abundant bacterium belonging to the genus Rickettsia that is closely related to Rickettsia ricketsii, a human pathogen vectored by ticks. No obvious masses of the Rickettsia bacterium were observed in louse tissues, nor did we find any evidence of vertical transmission, so the nature of its association remains unclear. IMPORTANCE Many insects are host to heritable symbiotic bacteria. These heritable bacteria have been identified from numerous species of parasitic lice. It appears that novel symbioses have formed between lice and bacteria many times, with new bacterial symbionts potentially replacing existing ones. However, little was known about the symbionts of lice parasitizing marine mammals. Here, we identified a heritable bacterial symbiont in lice parasitizing northern fur seals. This bacterial symbiont appears to have been recently acquired by the lice. The findings reported here provide insights

  1. From Eradication to Resistance: Five Continuing Concerns About Pediculosis.

    ERIC Educational Resources Information Center

    Brainerd, Elaine

    1998-01-01

    Discusses the five major concerns that govern a school nurse's thinking in managing head louse infestations, including dispelling misconceptions about head lice; ensuring that infestations are not missed; ensuring that parents understand instructions for effective treatment; educating the community about the correct use of pediculicides; and…

  2. Characterization of 10 microsatellite loci in an avian louse, Degeeriella regalis (Phthiraptera: Ischnocera: Philopteridae).

    PubMed

    Peters, Maureen B; Hagen, Cris; Whiteman, Noah K; Parker, Patricia G; Glenn, Travis C

    2009-05-01

    We isolated and characterized 10 polymorphic microsatellite loci in an ischnoceran louse, Degeeriella regalis, which parasitizes the threatened Galápagos hawk (Buteo galapagoensis) and other falconiform birds. The loci were screened across 30 individuals from two island populations in the Galápagos Islands. The number of alleles per locus ranged from two to 28. Polymorphic information content ranged from 0.14 to 0.94 and observed heterozygosity ranged from 0 to 0.67. These markers will be valuable in comparative population genetics studies in this species, which is the focus of a long-term population and disease ecology research program. PMID:21564777

  3. [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

  4. 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 ...

  5. 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…

  6. Identification of Different Bartonella Species in the Cattle Tail Louse (Haematopinus quadripertusus) and in Cattle Blood

    PubMed Central

    Gutiérrez, Ricardo; Cohen, Liron; Morick, Danny; Mumcuoglu, Kosta Y.; Harrus, Shimon

    2014-01-01

    Bartonella spp. are worldwide-distributed facultative intracellular bacteria that exhibit an immense genomic diversity across mammal and arthropod hosts. The occurrence of cattle-associated Bartonella species was investigated in the cattle tail louse Haematopinus quadripertusus and in dairy cattle blood from Israel. Lice were collected from cattle from two dairy farms during summer 2011, and both lice and cow blood samples were collected from additional seven farms during the successive winter. The lice were identified morphologically and molecularly using 18S rRNA sequencing. Thereafter, they were screened for Bartonella DNA by conventional and real-time PCR assays using four partial genetic loci (gltA, rpoB, ssrA, and internal transcribed spacer [ITS]). A potentially novel Bartonella variant, closely related to other ruminant bartonellae, was identified in 11 of 13 louse pools collected in summer. In the cattle blood, the prevalence of Bartonella infection was 38%, identified as B. bovis and B. henselae (24 and 12%, respectively). A third genotype, closely related to Bartonella melophagi and Bartonella chomelii (based on the ssrA gene) and to B. bovis (based on the ITS sequence) was identified in a single cow. The relatively high prevalence of these Bartonella species in cattle and the occurrence of phylogenetically diverse Bartonella variants in both cattle and their lice suggest the potential role of this animal system in the generation of Bartonella species diversity. PMID:24973066

  7. EST and mitochondrial DNA sequences support a distinct Pacific form of salmon louse, Lepeophtheirus salmonis.

    PubMed

    Yazawa, Ryosuke; Yasuike, Motoshige; Leong, Jong; von Schalburg, Kristian R; Cooper, Glenn A; Beetz-Sargent, Marianne; Robb, Adrienne; Davidson, William S; Jones, Simon R M; Koop, Ben F

    2008-01-01

    Nuclear deoxyribonucleic acid sequences from approximately 15,000 salmon louse expressed sequence tags (ESTs), the complete mitochondrial genome (16,148bp) of salmon louse, and 16S ribosomal ribonucleic acid (rRNA) and cytochrome oxidase subunit I (COI) genes from 68 salmon lice collected from Japan, Alaska, and western Canada support a Pacific lineage of Lepeophtheirus salmonis that is distinct from that occurring in the Atlantic Ocean. On average, nuclear genes are 3.2% different, the complete mitochondrial genome is 7.1% different, and 16S rRNA and COI genes are 4.2% and 6.1% different, respectively. Reduced genetic diversity within the Pacific form of L. salmonis is consistent with an introduction into the Pacific from the Atlantic Ocean. The level of divergence is consistent with the hypothesis that the Pacific form of L. salmonis coevolved with Pacific salmon (Onchorhynchus spp.) and the Atlantic form coevolved with Atlantic salmonids (Salmo spp.) independently for the last 2.5-11 million years. The level of genetic divergence coincides with the opportunity for migration of fish between the Atlantic and Pacific Ocean basins via the Arctic Ocean with the opening of the Bering Strait, approximately 5 million years ago. The genetic differences may help explain apparent differences in pathogenicity and environmental sensitivity documented for the Atlantic and Pacific forms of L. salmonis. PMID:18574633

  8. Sarcoptic mange infestation in pigs: an overview.

    PubMed

    Laha, R

    2015-12-01

    Sarcoptic mange infestation in pigs is caused by Sarcoptes scabiei var. suis. It is the most common mange infestation of pigs. The parasite is distributed worldwide. Pig owners are generally concerned about the internal parasitic infections and ignored the external parasitic infestations. But the external parasitic infestation with S. scabiei var. suis has economic significance as it causes morbidity, mortality, decreased fertility and feed conversion ratio in pigs. Keeping in view of importance of S. scabies var. suis infestation in pigs, this communication discussed about the present and past research works done on S. scabies var. suis infestation in pigs, particularly its prevalence, life cycle, pathological lesions, clinical symptoms, haematobiochemical changes, diagnosis, treatment and control, to have an idea about this infestation at a glance. It has been concluded that the research work done on sarcoptic mange infestation in pigs in India is less in comparison to other countries. It may be due to its consideration as a neglected parasite or due to it's under report. Organization of awareness programs for the farmers by extension personalities or other authorities might be able to save the farmers from economic losses due to this infestation. PMID:26688620

  9. Presence and effects of the dog louse Trichodectes canis (Mallophaga, Trichodectidae) on wolves and coyotes from Minnesota and Wisconsin

    USGS Publications Warehouse

    Mech, L.D.; Thiel, R.P.; Fritts, S.H.; Berg, W.E.

    1985-01-01

    The dog louse was found on 19 wolves (Canis lupus) and six coyotes (C. latrans) from Minnesota and Wisconsin during the July-February, 1973 through 1983, period. No evidence was found that lice had any serious effect on wolf survival.

  10. Negative Feedbacks on Bark Beetle Outbreaks: Widespread and Severe Spruce Beetle Infestation Restricts Subsequent Infestation

    PubMed Central

    Hart, Sarah J.; Veblen, Thomas T.; Mietkiewicz, Nathan; Kulakowski, Dominik

    2015-01-01

    Understanding disturbance interactions and their ecological consequences remains a major challenge for research on the response of forests to a changing climate. When, where, and how one disturbance may alter the severity, extent, or occurrence probability of a subsequent disturbance is encapsulated by the concept of linked disturbances. Here, we evaluated 1) how climate and forest habitat variables, including disturbance history, interact to drive 2000s spruce beetle (Dendroctonus rufipennis) infestation of Engelmann spruce (Picea engelmannii) across the Southern Rocky Mountains; and 2) how previous spruce beetle infestation affects subsequent infestation across the Flat Tops Wilderness in northwestern Colorado, which experienced a severe landscape-scale spruce beetle infestation in the 1940s. We hypothesized that drought and warm temperatures would promote infestation, whereas small diameter and non-host trees, which may reflect past disturbance by spruce beetles, would inhibit infestation. Across the Southern Rocky Mountains, we found that climate and forest structure interacted to drive the 2000s infestation. Within the Flat Tops study area we found that stands infested in the 1940s were composed of higher proportions of small diameter and non-host trees ca. 60 years later. In this area, the 2000s infestation was constrained by a paucity of large diameter host trees (> 23 cm at diameter breast height), not climate. This suggests that there has not been sufficient time for trees to grow large enough to become susceptible to infestation. Concordantly, we found no overlap between areas affected by the 1940s infestation and the current infestation. These results show a severe spruce beetle infestation, which results in the depletion of susceptible hosts, can create a landscape template reducing the potential for future infestations. PMID:26000906

  11. Negative feedbacks on bark beetle outbreaks: widespread and severe spruce beetle infestation restricts subsequent infestation.

    PubMed

    Hart, Sarah J; Veblen, Thomas T; Mietkiewicz, Nathan; Kulakowski, Dominik

    2015-01-01

    Understanding disturbance interactions and their ecological consequences remains a major challenge for research on the response of forests to a changing climate. When, where, and how one disturbance may alter the severity, extent, or occurrence probability of a subsequent disturbance is encapsulated by the concept of linked disturbances. Here, we evaluated 1) how climate and forest habitat variables, including disturbance history, interact to drive 2000s spruce beetle (Dendroctonus rufipennis) infestation of Engelmann spruce (Picea engelmannii) across the Southern Rocky Mountains; and 2) how previous spruce beetle infestation affects subsequent infestation across the Flat Tops Wilderness in northwestern Colorado, which experienced a severe landscape-scale spruce beetle infestation in the 1940s. We hypothesized that drought and warm temperatures would promote infestation, whereas small diameter and non-host trees, which may reflect past disturbance by spruce beetles, would inhibit infestation. Across the Southern Rocky Mountains, we found that climate and forest structure interacted to drive the 2000s infestation. Within the Flat Tops study area we found that stands infested in the 1940s were composed of higher proportions of small diameter and non-host trees ca. 60 years later. In this area, the 2000s infestation was constrained by a paucity of large diameter host trees (> 23 cm at diameter breast height), not climate. This suggests that there has not been sufficient time for trees to grow large enough to become susceptible to infestation. Concordantly, we found no overlap between areas affected by the 1940s infestation and the current infestation. These results show a severe spruce beetle infestation, which results in the depletion of susceptible hosts, can create a landscape template reducing the potential for future infestations. PMID:26000906

  12. A remarkable new genus and a new species of chewing louse (Phthiraptera, Ischnocera, Philopteridae) from Brazil

    PubMed Central

    Valim, Michel P.; Cicchino, Armando C.

    2015-01-01

    Abstract A new genus of chewing louse as Bobdalgleishia, and its type species Bobdalgleishia stephanophallus sp. n. (Phthiraptera) belonging to the Brueelia-complex (Ischnocera: Philopteridae) are described. Adults of the new species are fully described, illustrated and compared morphologically with the type species of Motmotnirmus Mey & Barker, 2014, which is its closest relative. The type host of Bobdalgleishia stephanophallus is a subspecies of the great jacamar Jacamerops aureus ridgwayi Todd, 1943, an endemic Amazonian bird distributed in northern Brazil, and the type locality is the State of Pará. Bobdalgleishia is a remarkable genus with unique morphological and chaetotaxic characters which readily separate it from other members of the Brueelia-complex, in particular by having the first two marginal temporal and ocular setae very long. PMID:26798280

  13. Toxicity of essential and non-essential oils against the chewing louse, Bovicola (Werneckiella) ocellatus.

    PubMed

    Talbert, R; Wall, R

    2012-10-01

    The toxicity of six plant essential oils to the chewing louse, Bovicola (Werneckiella) ocellatus collected from donkeys, was examined in laboratory bioassays. The oils examined were: tea-tree (Melaleuca alternifolia), lavender (Lavandula angustifolia), peppermint (Mentha piperita), eucalyptus (Eucalyptus globulus Labillardiere), clove bud (Eugenia caryophyllata) and camphor (Cinnamomum camphora). All except camphor oil showed high levels of toxicity, with significant dose-dependent mortality and an LC(50) at concentrations of below 2% (v/v). Hundred percent mortality was achieved at concentrations of 5-10% (v/v). Two essential oil components: eugenol and (+)-terpinen-4-ol showed similar levels of toxicity. The data suggest that these botanical products may offer environmentally and toxicologically safe, alternative veterinary pediculicides for the control of ectoparasitic lice. PMID:22177577

  14. Bovicola tibialis (Phthiraptera:Trichodectidae): occurrence of an exotic chewing louse on cervids in North America.

    PubMed

    Mertins, James W; Mortenson, Jack A; Bernatowicz, Jeffrey A; Hall, P Briggs

    2011-01-01

    Through a recent (2003-2007) survey of ectoparasites on hoofed mammals in western North America, a literature review, and examination of archived museum specimens, we found that the exotic deer-chewing louse, Bovicola tibialis (Piaget), is a long-term, widespread resident in the region. The earliest known collection was from Salt Spring Island, Canada, in 1941. We found these lice on the typical host, that is, introduced European fallow deer (Dama dama L.), and on Asian chital (Axis axis [Erxleben] ), native Columbian black-tailed deer (Odocoileus hemionus columbianus [Richardson] ), and Rocky Mountain mule deer (O. h. hemionus [Rafinesque]) x black-tailed deer hybrids. Chital and the hybrid deer are new host records. All identified hosts were known to be or probably were exposed to fallow deer. Geographic records include southwestern British Columbia, Canada; Marin and Mendocino Counties, California; Deschutes, Lincoln, and Linn Counties, Oregon; Yakima and Kittitas Counties, Washington; Curry County, New Mexico; and circumstantially, at least, Kerr County, Texas. All but the Canadian and Mendocino County records are new. Bovicola tibialis displays a number of noteworthy similarities to another exotic deer-chewing louse already established in the region, that is, Damalinia (Cervicola) sp., which is associated with a severe hair-loss syndrome in black-tailed deer. We discuss longstanding problems with proper identification of B. tibialis, the probability that it occurs even more widely in the United States, and the prospects for it to cause health problems for North American deer. Additional information gathered since our active survey establishes further new distribution and host records for B. tibialis. PMID:21337942

  15. 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

  16. 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

  17. Lousicidal, ovicidal and repellent efficacy of some essential oils against lice and flies infesting water buffaloes in Egypt.

    PubMed

    Khater, Hanem F; Ramadan, Mohamed Y; El-Madawy, Reham S

    2009-10-14

    The lousicidal and repellent effects of five essential oils were investigated for the first time against the buffalo louse, Haematopinus tuberculatus, and flies infesting water buffaloes in Qalyubia Governorate, Egypt. For the in vitro studies, filter paper contact bioassays were used to test the oils and their lethal activities were compared with that of d-phenothrin. Four minutes post-treatment, the median lethal concentration, LC50, values were 2.74, 7.28, 12.35, 18.67 and 22.79% for camphor (Cinnamomum camphora), onion (Allium cepa), peppermint (Mentha piperita), chamomile (Matricaria chamomilla) and rosemary oils (Rosmarinus officinalis), respectively, whereas for d-phenothrin, it was 1.17%. The lethal time (50) (LT50) values were 0.89, 2.75, 15.39, 21.32, 11.60 and 1.94 min after treatment with 7.5% camphor, onion, peppermint, chamomile, rosemary and d-phenothrin, respectively. All the materials used except rosemary, which was not applied, were ovicidal to the eggs of H. tuberculatus. Despite the results of the in vitro assays, the in vivo treatments revealed that the pediculicidal activity was more pronounced with oils. All treated lice were killed after 0.5-2 min, whereas with d-phenothrin, 100% mortality was reached only after 120 min. The number of lice infesting buffaloes was significantly reduced 3, 6, 4, 6 and 9 days after treatment with camphor, peppermint, chamomile, onion, and d-phenothrin, respectively. Moreover, the oils and d-phenothrin significantly repelled flies, Musca domestica, Stomoxys calcitrans, Haematobia irritans and Hippobosca equina, for 6 and 3 days post-treatment, respectively. No adverse effects were noted on either animals or pour-on operators after exposure to the applied materials. Consequently, some Egyptian essential oils show potential for the development of new, speedy and safe lousicides and insect repellents for controlling lice and flies which infest water buffaloes. PMID:19596520

  18. [Imported infestations of nasopharyngeal parasites in dogs].

    PubMed

    Gothe, R; Barutzki, D; Schöl, H; Heinen, H

    1991-02-01

    In this paper infestations of the nasal cavity with Myxobdella annandalei in a dog after a sojourn in Nepal and with Linguatula serrata in 2 stray dogs from Turkey, which were imported to Germany, are described. PMID:2048114

  19. Distribution of phytopathogenic bacteria in infested seeds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Populations of phytopathogenic bacteria representing five host-pathogen combinations were assessed to determine if there was a mathematical relationship common across seedborne bacterial diseases. Bacterial populations were estimated from naturally-infested seeds of cowpea (Vigna unguiculata), peppe...

  20. Controlling zebra mussel infestations at hydroelectric plants

    SciTech Connect

    Sblendorio, R.P.; Malinchock, J.C. ); Claudi, R. )

    1991-07-01

    U.S. and Canadian utilities in the great lakes area have adopted techniques to temporarily prevent infestation of the zebra mussel in their hydro facilities, but are still looking for more permanent solutions.

  1. Genomic Characterization and Phylogenetic Position of Two New Species in Rhabdoviridae Infecting the Parasitic Copepod, Salmon Louse (Lepeophtheirus salmonis)

    PubMed Central

    Økland, Arnfinn Lodden; Nylund, Are; Øvergård, Aina-Cathrine; Blindheim, Steffen; Watanabe, Kuninori; Grotmol, Sindre; Arnesen, Carl-Erik; Plarre, Heidrun

    2014-01-01

    Several new viruses have emerged during farming of salmonids in the North Atlantic causing large losses to the industry. Still the blood feeding copepod parasite, Lepeophtheirus salmonis, remains the major challenge for the industry. Histological examinations of this parasite have revealed the presence of several virus-like particles including some with morphologies similar to rhabdoviruses. This study is the first description of the genome and target tissues of two new species of rhabdoviruses associated with pathology in the salmon louse. Salmon lice were collected at different Atlantic salmon (Salmo salar) farming sites on the west coast of Norway and prepared for histology, transmission electron microscopy and Illumina sequencing of the complete RNA extracted from these lice. The nearly complete genomes, around 11 600 nucleotides encoding the five typical rhabdovirus genes N, P, M, G and L, of two new species were obtained. The genome sequences, the putative protein sequences, and predicted transcription strategies for the two viruses are presented. Phylogenetic analyses of the putative N and L proteins indicated closest similarity to the Sigmavirus/Dimarhabdoviruses cluster, however, the genomes of both new viruses are significantly diverged with no close affinity to any of the existing rhabdovirus genera. In situ hybridization, targeting the N protein genes, showed that the viruses were present in the same glandular tissues as the observed rhabdovirus-like particles. Both viruses were present in all developmental stages of the salmon louse, and associated with necrosis of glandular tissues in adult lice. As the two viruses were present in eggs and free-living planktonic stages of the salmon louse vertical, transmission of the viruses are suggested. The tissues of the lice host, Atlantic salmon, with the exception of skin at the attachment site for the salmon louse chalimi stages, were negative for these two viruses. PMID:25402203

  2. Small bowel Ascaris infestation: a diagnostic challenge.

    PubMed

    Khan, Muhammad Waqas; Ghauri, Sanniya Khan

    2016-01-01

    Ascariasis is a common infestation in developing countries where there is poor hygiene. A majority of the cases are asymptomatic, with a few cases presenting with mild abdominal pain and nutritional deficiencies in the long term. Here we present a case of a young boy who presented as a diagnostic dilemma, with signs of acute intestinal obstruction without any supporting radiological evidence. A barium study revealed the presence of low-burden Ascaris infestation that was managed medically. PMID:27175091

  3. Small bowel Ascaris infestation: a diagnostic challenge

    PubMed Central

    Khan, Muhammad Waqas; Ghauri, Sanniya Khan

    2016-01-01

    Ascariasis is a common infestation in developing countries where there is poor hygiene. A majority of the cases are asymptomatic, with a few cases presenting with mild abdominal pain and nutritional deficiencies in the long term. Here we present a case of a young boy who presented as a diagnostic dilemma, with signs of acute intestinal obstruction without any supporting radiological evidence. A barium study revealed the presence of low-burden Ascaris infestation that was managed medically. PMID:27175091

  4. Heads Up

    MedlinePlus

    ... Juvenil HEADS UP to School Sports Online Concussion Training Coaches Parents Athletes Sports Officials HEADS UP to Schools School Nurses Teachers, Counselors, and School Professionals Parents HEADS UP ...

  5. 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

  6. 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

  7. Head lice

    MedlinePlus

    ... Practice of Infectious Diseases . 8th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 294. Elston DM. Arthropods and ... eds. Goldman's Cecil Medicine . 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 359 Habif TP. Infestations and ...

  8. 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

  9. Delusional infestation: are you being bugged?

    PubMed

    Thakkar, Angeli; Ooi, Kenneth Gj; Assaad, Nagi; Coroneo, Minas

    2015-01-01

    This case report documents a 58-year-old male who presented to the clinic with a 12-month history of a burrowing sensation in his eyelids that he attributed to a parasitic infestation. After being extensively investigated and reviewed by relevant specialties, no evidence of parasitic infestation was found. He was diagnosed with and treated for blepharitis. Psychiatric referral for presumed delusional infestation (DI) was recommended. Despite this, he remained insistent in his belief of infestation, and was inevitably lost to follow-up. DI, previously known as delusional parasitosis, is a rare delusional disorder where affected individuals have a fixed, false belief that they have a parasitic infestation. Diagnosis can be challenging. Practitioners need to evaluate between primary and secondary DI carefully, as management differs depending on the etiology. Despite this, patients diagnosed with primary DI tend to be resistant to psychiatric referral. This report aims to optimize management by giving the reader a guideline for appropriate investigations and advice on patient approach. It is important to recognize hallmark features of DI to minimize self-inflicted trauma and associated psychosocial consequences. Effective treatment for DI is available, and devastating consequences, including blindness, can be avoided. PMID:26082608

  10. 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

  11. Comparison of antibiotic regimens for treating louse-borne relapsing fever: a meta-analysis.

    PubMed

    Guerrier, Gilles; Doherty, Tom

    2011-09-01

    The optimum treatment for louse-borne relapsing fever (LBRF) has not been fully established. Eliminating spirochetes is often associated with the potentially lethal Jarisch-Herxheimer reaction (JHR). The objective of this meta-analysis was to review the evidence supporting the use of antibiotics usually employed for treating LBRF. A systematic review of the literature was performed to identify randomised controlled trials (RCT) comparing antibiotics in LBRF. The primary outcome was mortality, whilst JHR rates, relapse rates, time to fever clearance and time to spirochete disappearance were secondary outcomes. Six RCTs performed in Ethiopia were included. Trials were small and often of limited quality, using single-dose therapy with either penicillin or tetracycline. There was no significant difference between tetracycline and penicillin with regard to mortality rate. Although there was significant heterogeneity between the five trials comparing the rate of JHRs, three of them showed a significant benefit in favour of penicillin. The risk of relapse was reduced with tetracycline. Tetracycline use was associated with a lower mean fever clearance time. Tetracycline appears to be the most efficient drug but also appears to be associated with a higher rate of JHRs. Alternative regimens to treat LBRF should be investigated. PMID:21803390

  12. 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

  13. 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

  14. Heartworm (Acanthocheilonema spirocauda) and seal louse (Echinophthirius horridus) infections in harbour seals (Phoca vitulina) from the North and Baltic Seas

    NASA Astrophysics Data System (ADS)

    Lehnert, Kristina; Schwanke, Eva; Hahn, Kerstin; Wohlsein, Peter; Siebert, Ursula

    2016-07-01

    The seal louse (Echinophthirius [E.] horridus) and the heartworm (Acanthocheilonema [A.] spirocauda) are parasites of harbour seal (Phoca vitulina). Little is known about the role of the seal louse as a potential vector and its role for the development and transmission of heartworm larvae to their final host, the harbour seal. The life-cycle of the heartworm is still not fully understood. For the presented study, findings of 1191 stranded harbour seals collected along the North- and Baltic Sea coast between 1996 and 2013 were examined. 4.4% (n = 53) of these harbour seals were infected with adult heartworms and 3.4% (n = 40) harbour seals carried seal lice. The highest prevalence and level of infection with adult heartworms (A. spirocauda) (9.3%) and seal lice (E. horridus) (8.9%) were found on yearling harbour seals (7-18 months) compared to neonate and adult seals. Investigating seal lice (n = 35) for larval heartworm stages one larvae was encountered in an ethanol-fixated seal louse. During a health monitoring survey of live harbour seals, 109 animals were captured and examined during spring and autumn between 2008 and 2014. Blood samples were taken and microfilariae were discovered in blood smears in 41% (n = 45) of the examined harbour seals. Yearling seals (n = 21) showed higher prevalence (86%) and level of infection with microfilariae than adults. Microfilariae were identified as A. spirocauda by sequencing the species-specific COI gene in 24 blood samples. The high prevalence of microfilariae of A. spirocauda in blood samples (41%) is in contrast to the low prevalence of mature infections/adult specimens in stranded seals (4.4%) investigated. Although rare parasites of seals, the recent increase in prevalence of heartworm and seal lice in stranded seals and the relatively high occurrence of microfilaria in the free-ranging population underscore the importance of further studies investigating the immunology of infections and their transmission pathways, as

  15. Head Injuries

    MedlinePlus

    ... of head injuries include bicycle or motorcycle wrecks, sports injuries, falls from windows (especially among children who live ... to watch for? When can I start playing sports again after a head injury? How can brain damage from a head injury ...

  16. Head circumference

    MedlinePlus

    ... a child's head circumference Normal ranges for a child's sex and age (weeks, months), based on values that experts have obtained for normal growth rates of infants' and children's heads Measurement of the head circumference is an ...

  17. 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 ...

  18. Parasitoid infestation changes female mating preferences.

    PubMed

    Beckers, Oliver M; Wagner, William E

    2013-04-01

    Females often adjust their mating preference to environmental and social conditions. This plasticity of preference can be adaptive for females and can have important consequences for the evolution of male traits. While predation and parasitism are widespread, their effects on female preferences have rarely been investigated. Females of the cricket Gryllus lineaticeps are parasitized by the parasitoid fly Ormia ochracea. Infestation with fly larvae substantially reduces female life span and thus reproductive opportunities of the cricket. Both female G. lineaticeps and flies orient to male song and both prefer male songs with faster chirp rates to songs with slower chirp rates. We tested the effect of parasitic infestation on female responsiveness to male song and female chirp rate preferences. The proportion of individuals responding to male songs did not differ between infested and control females. Control females preferred intermediate chirp rates to slow chirp rates and did not discriminate between fast and intermediate chirp rates. In contrast, infested females showed no preferences in the choice trials, indicating reduced chirp rate selectivity. This plasticity in female preferences may be adaptive; parasitized females may have a higher probability of reproducing before they are killed by the parasitoids if they are less selective (i.e. there will be a larger pool of males considered acceptable). The change in preferences suggests relaxed selection on male chirp rate during times of parasitism. PMID:24347669

  19. Parasitoid infestation changes female mating preferences

    PubMed Central

    Beckers, Oliver M.; Wagner, William E.

    2013-01-01

    Females often adjust their mating preference to environmental and social conditions. This plasticity of preference can be adaptive for females and can have important consequences for the evolution of male traits. While predation and parasitism are widespread, their effects on female preferences have rarely been investigated. Females of the cricket Gryllus lineaticeps are parasitized by the parasitoid fly Ormia ochracea. Infestation with fly larvae substantially reduces female life span and thus reproductive opportunities of the cricket. Both female G. lineaticeps and flies orient to male song and both prefer male songs with faster chirp rates to songs with slower chirp rates. We tested the effect of parasitic infestation on female responsiveness to male song and female chirp rate preferences. The proportion of individuals responding to male songs did not differ between infested and control females. Control females preferred intermediate chirp rates to slow chirp rates and did not discriminate between fast and intermediate chirp rates. In contrast, infested females showed no preferences in the choice trials, indicating reduced chirp rate selectivity. This plasticity in female preferences may be adaptive; parasitized females may have a higher probability of reproducing before they are killed by the parasitoids if they are less selective (i.e. there will be a larger pool of males considered acceptable). The change in preferences suggests relaxed selection on male chirp rate during times of parasitism. PMID:24347669

  20. Identification and characterisation of hemocyanin of the fish louse Argulus (Crustacea: Branchiura).

    PubMed

    Pinnow, Pauline; Fabrizius, Andrej; Pick, Christian; Burmester, Thorsten

    2016-02-01

    Hemocyanin transports oxygen in the hemolymph of many arthropod species. Within the crustaceans, this copper-containing protein was thought to be restricted to Malacostraca, while other crustacean classes were assumed to employ hemoglobin or lack any respiratory protein. Only recently it has become evident that hemocyanins also occur in Remipedia and Ostracoda. Here we report for the first time the identification and characterisation of hemocyanin in the fish louse Argulus, which belongs to the class of Branchiura. This finding indicates that hemocyanin was the principal oxygen carrier in the stem lineage of the pancrustaceans, but has been lost independently multiple times in crustacean taxa. We obtained the full-length cDNA sequences of two hemocyanin subunits of Argulus foliaceus by a combination of RT-PCR, RACE and Illumina sequencing of the transcriptome. In addition, one full-length and one partial cDNA sequence were derived from the transcriptome data of Argulus siamensis. Western blot analysis confirmed the presence of at least two hemocyanin subunits in A. foliaceus, which are expressed at the mRNA level at a 1:3.5 ratio. The addition to the branchiuran hemocyanin subunits to a multiple sequence alignment of arthropod, hemocyanins improved the phylogenetic resolution within the pancrustacean hemocyanins. Malacostracan, ostracod and branchiuran hemocyanins are distinct from the hexapod and remipede hemocyanins, reinforcing the hypothesis of a close relationship of Remipedia and Hexapoda. Notably, the ostracod hemocyanins are paraphyletic with respect to the branchiuran hemocyanins, indicating ancient divergence and differential loss of distinct subunit types. PMID:26515963

  1. Signature Chemicals for Detection of Hidden Insect Infestation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tephritid fruit flies are major pests worldwide, but infestation is difficult to detect since the larval stages are concealed within host fruits. Using grapefruit infested with the Caribbean fruit fly, we evaluated gas chromatography (GC) as a tool for detection of hidden infestation. We found sever...

  2. Epidemiology of Oestrus ovis (Linneo, 1761) infestation in goats in Spain.

    PubMed

    Alcaide, M; Reina, D; Frontera, E; Navarrete, I

    2005-06-30

    This survey was conducted to determine the chronobiology and seroprevalence of nasal bot infestation (Oestrus ovis) in Spain and to identify the risk factors associated with this disease in caprine herds. A total of 1590 sera from adult goats were collected at random on 175 farms in southwestern Spain. Sera were tested by ELISA, using crude protein from second stage larvae as antigen. The mean seroprevalence was 46.04% and mean percentage of optical densities was 41.83. These data indicate a high prevalence of this parasite in the investigated areas. The serological survey revealed that goats managed at higher altitudes, at meridians latitudes and on farms with small herds had a smaller probability of infestation. Eighty goat heads, obtained from abattoirs in the central region of Spain, were collected and examined for nasal botflies from February to October 2002. O. ovis larval stages were recovered from the nasal-sinus cavities of 23 goats, reaching a prevalence of 34.94%. The mean larval burden was 3.9 larvae per infested head. No first instars were found during February and March, when the second instar reached its larger count. The third instar was observed in very small number during the whole period of study, with one peak occurring in July--August. These data show the existence of a favourable period for the development of larval instars of O. ovis in goats that starts in February and finishes in September. PMID:15899552

  3. Residual and ovicidal efficacy of essential oil-based formulations in vitro against the donkey chewing louse Bovicola ocellatus.

    PubMed

    Sands, B; Ellse, L; Wall, R

    2016-03-01

    Essential oils have shown good experimental potential as novel veterinary ectoparasiticides. However, if they are to be used as veterinary products, they must be available in formulations that are suitable for practical application against specific ectoparasites. Here, the efficacies of formulations containing 5% (v/v) lavender or tea tree oil, in combination with two emulsifiers [a surfactant, 5% (w/v) N-lauroylsarcosine sodium salt (SLS), and a soluble polymer, 5% (w/v) polyvinylpyrrolidone (PVP)], with or without 10% coconut oil, were tested in contact bioassays against the donkey chewing louse Bovicola ocellatus (Piaget) (Phthiraptera: Trichodectidae). Residual activity was quantified in open and closed containers; ovicidal efficacy was also examined. Exposure to either of 5% (v/v) lavender or tea tree oils with SLS or PVP resulted in louse mortality of 100%, but when coconut oil was included as an excipient, significantly lower efficacy was recorded. However, the formulations became significantly less effective after 2 h in open containers and 40 h in closed containers. The results confirm that the residual activity of essential oils is relatively transitory and the addition of 10% coconut oil does not prolong the period of insecticidal activity by slowing essential oil evaporation. Too short a period of residual activity is likely to be a significant impediment to the effective practical use of essential oils. However, unlike many synthetic pediculicides, the essential oils tested here were highly ovicidal, which suggests that prolonged residual activity may not be essential to kill newly hatched nymphs after treatment. PMID:26522385

  4. 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

  5. Molecular characterisation and functional analysis of LsChi2, a chitinase found in the salmon louse (Lepeophtheirus salmonis salmonis, Krøyer 1838).

    PubMed

    Eichner, Christiane; Harasimczuk, Ewa; Nilsen, Frank; Grotmol, Sindre; Dalvin, Sussie

    2015-01-01

    The salmon louse (Lepeophtheirus salmonis spp.) is an economically important parasite on Atlantic salmon reared in aquaculture globally. Production and degradation of chitin, a major component of the exoskeleton, is the target of some pesticides (Di/Teflubenzuron) used in management of lice on farmed fish. These chemicals inhibit molting of the salmon louse leading to the death of the parasite. We found three chitinases (LsChi1, LsChi2 and LsChi4) in the salmon louse genome. Sequence analysis and phylogeny showed that they belong to the GH18 type of chitinase group and show high sequence similarity to chitinases found in other crustaceans and in insects. Expression patterns were different for all three chitinases suggesting different functions during louse development. Furthermore, the function of LsChi2 was further explored through the use of RNA interference and infection trials. Copepodids with knock down of LsChi2 transcripts were deformed and showed a highly reduced infection success. PMID:25643862

  6. The sea louse Lepeophtheirus acutus (Caligidae, Siphonostomatoida, Copepoda) as a pathogen of aquarium-held elasmobranchs.

    PubMed

    Kik, M J L; Janse, M; Benz, G W

    2011-10-01

    Lepeophtheirus acutus Heegaard, 1943 (Caligidae, Siphonostomatoida, Copepoda), was collected from or observed on four of six elasmobranch species held at Burgers' Zoo (Arnhem, The Netherlands). Circumstantial evidence suggested that a zebra shark, Stegostoma fasciatum (Hermann), from the wild carried the infection into the facility, where copepods reproduced and colonized additional hosts. Copepods typically attached on and about the eyes, in the mouth and occasionally about the cloaca and on the claspers. Severe ocular lesions were associated with infections on zebra sharks, a grey reef shark, Carcharhinus amblyrhynchos (Bleeker), whitetip reef sharks, Triaenodon obesus (Rüppell), and giant shovelnose ray, Rhinobatos typus Bennett, while blacktip reef sharks, Carcharhinus melanopterus (Quoy & Gaimard), and blacktip sharks, Carcharhinus limbatus (Valenciennes), living in infested aquaria showed no sign of infection. Water treatments using trichlorfon were considered primarily responsible for the eradication of copepods from hosts and infested aquaria. This case is the first report of a copepod infection being closely associated with disease and death of an aquarium-held elasmobranch. Given its ability to infect a wide variety of elasmobranchs and promote life-threatening lesions on some hosts, L. acutus should be considered a dangerous pathogen of captive elasmobranchs. PMID:21916904

  7. Nasal leech infestation causing persistent epistaxis

    PubMed Central

    Sarathi, Kalra

    2011-01-01

    Foreign bodies in the nasal cavity are commonly encountered as a cause of epistaxis; however, nasal leech infestation as a cause of unilateral persistent epistaxis is very rare. Examination of nasal cavity revealed fleshy material in the left nostril, which was identified as leech. The leech was removed with the help of an artery forceps following irrigation of the left nostril with normal saline and adopting wait-and-watch policy. In developing countries, leech infestation as a cause of epistaxis should be suspected in patients with lower socioeconomic status or in those living in rural areas who give history of drinking polluted water from, or bathing in, stagnant ponds and puddles. PMID:21887037

  8. 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

  9. Botfly infestation (myiasis) masquerading as furunculosis.

    PubMed

    Gewirtzman, A; Rabinovitz, H

    1999-02-01

    With air travel so prevalent, diseases endemic to certain regions may appear anywhere. The botfly (Dermatobia hominis) is not native to North America. We describe a case of a young boy and his father who presented with furunculosis secondary to infestation with the botfly. The infected patients live in South Florida and had been vacationing in Central America. Standard surgical treatment as well as multiple native remedies are described. PMID:10071732

  10. Demodex musculi Infestation in Genetically Immunomodulated Mice.

    PubMed

    Smith, Peter C; Zeiss, Caroline J; Beck, Amanda P; Scholz, Jodi A

    2016-01-01

    Demodex musculi, a prostigmatid mite that has been reported infrequently in laboratory mice, has been identified with increasing frequency in contemporary colonies of immunodeficient mice. Here we describe 2 episodes of D. musculi infestation with associated clinical signs in various genetically engineered mouse strains, as well as treatment strategies and an investigation into transmissibility and host susceptibility. The first case involved D. musculi associated with clinical signs and pathologic lesions in BALB/c-Tg(DO11.10)Il13(tm) mice, which have a defect in type 2 helper T cell (Th2) immunity. Subsequent investigation revealed mite transmission to both parental strains (BALB/c-Tg[DO11.10] and BALB/c-Il13(tm)), BALB/c-Il13/Il4(tm), and wild-type BALB/c. All Tg(DO11.10)Il13(tm) mice remained infested throughout the investigation, and D. musculi were recovered from all strains when they were cohoused with BALB/c-Tg(DO11.10)Il13(tm) index mice. However, only Il13(tm) and Il13/Il4(tm) mice demonstrated persistent infestation after index mice were removed. Only BALB/c-Tg(DO11.10)Il13(tm) showed clinical signs, suggesting that the phenotypic dysfunction of Th2 immunity is sufficient for persistent infestation, whereas clinical disease associated with D. musculi appears to be genotype-specific. This pattern was further exemplified in the second case, which involved NOD.Cg-Prkdc(scid)Il2r(tm1Wjl)/SzJ (NSG) and C;129S4 Rag2(tm1.1Flv) Il2rg(tm1.1Flv)/J mice with varying degrees of blepharitis, conjunctivitis, and facial pruritis. Topical amitraz decreased mite burden but did not eliminate infestation or markedly ameliorate clinical signs. Furthermore, mite burden began to increase by 1 mo posttreatment, suggesting that topical amitraz is an ineffective treatment for D. musculi. These experiences illustrate the need for vigilance regarding opportunistic and uncommon pathogens in rodent colonies, especially among mice with immunologic deficits. PMID:27538858

  11. Head MRI

    MedlinePlus

    ... the head; MRI - cranial; NMR - cranial; Cranial MRI; Brain MRI; MRI - brain; MRI - head ... tell your health care provider if you have: Brain aneurysm clips Certain types of artificial heart valves ...

  12. Head Injuries

    MedlinePlus

    ... injuries internal head injuries, which may involve the skull, the blood vessels within the skull, or the brain Fortunately, most childhood falls or ... knock the brain into the side of the skull or tear blood vessels. Some internal head injuries ...

  13. 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 ...

  14. Epidemiology of flea infestation of ruminants in Libya.

    PubMed

    Kaal, J F; Baker, K; Torgerson, P R

    2006-11-01

    The results of an epidemiological and clinical study of flea infestations of farm animals in northern Libya is reported. Of 12,130 sheep examined from 124 flocks, 150 sheep were found to be infested with fleas from 50 different flocks. Likewise 23 goats from 2981 examined, and 11 calves from 1124 cattle examined were infested No fleas were recovered from camels or horses. Of 1861 fleas recovered from farm livestock, 1857 were Ctenocephalides felis strongylus and 4 were Pulex irritans. Dogs from farms and local clinics were also examined. Eight farms dogs were found to be infested with P. irritans. Of 79 infested dogs examined in veterinary clinics, 53 were found infested with P. irritans, 11 with Ctenocephalides felis felis, 12 had a mixed infestation of P. irritans and C. felis felis. Single dogs had mixed infestation of P. irritans and C. canis; C. felis felis and C. canis; and P. irritans, C. felis felis and Echidnophaga gallinacia. C. felis felis was also found on 15 infested cats. C. felis felis was never found on large farm animals despite frequently sharing their environment with dogs or cats. Likewise C. felis stongylus was never isolated from dogs or cats. This is consistent with the hypothesis that C. felis strongylus has become adapted to large farm animals, whilst C. felis felis is better adapted to dogs and cats. However, four stockmen were found infested with a total of 176 C. felis strongylus, which suggests that this subspecies is also a potential zoonosis. A significantly higher proportion of intensive farms had animals with flea infestation compared to semi-intensive farms. Fleas were not found in nomadic herds. Infested farm animals often presented with excoriation, alopecia, pruritus and hyperkeratitis particularly on the lower limbs. These signs are consistent with the generation of flea-bite hypersensitivity. PMID:16962246

  15. [Louse-borne-relapsing-fever in refugees from the Horn of Africa; a case series of 25 patients].

    PubMed

    Seilmaier, M; Guggemos, W; Wieser, A; Fingerle, V; Balzer, L; Fenzl, T; Hoch, M; von Both, U; Schmidt, H U; Wendtner, C M; Strobel, E

    2016-07-01

    Background | Relapsing fever is divided into tick borne relapsing fever (TBRF) and louse borne relapsing fever (LBRF). This report describes 25 refugees from East Africa who were diagnosed to suffer from LBRF within a period of 6 month only at a single hospital in Munich / Germany. Material & Methods | The aim was to point out common clinical features as well as laboratory findings and clinical symptoms before and after initiation of treatment in 25 patients with louse borne relapsing fever (LBRF) who were diagnosed and treated at Klinikum München Schwabing from August 2015 to January 2016. To the best of our knowledge this is the largest case series of LBRF in the western world for decades. Main focus of the investigation was put on clinical aspects. Results | All 25 patients suffered from acute onset of high fever with chills, headache and severe prostration. Laboratory analysis showed high CRP and a marked thrombocytopenia. A Giemsa blood stain was procured immediately in order to look for malaria. In the blood smear spirochetes with typical shape and aspect of borrelia species could be detected.The further PCR analysis confirmed infection with Borrelia recurrentis. Treatment with Doxycycline was started forthwith. The condition improved already on the second day after treatment was started and all were restored to health in less than a week. Apart from a mild to moderate Jarisch-Herxheimer-reaction we didn`t see any side effects of the therapy. Conclusion | LBRF has to be taken into account in feverish patients who come as refugees from East-Africa. It seems that our patients belong to a cluster which probably has its origin in Libya and more patients are to be expected in the near future. As LBRF might cause outbreaks in refugee camps it is pivotal to be aware of this emerging infectious disease in refugees from East-Africa. PMID:27404939

  16. Bacterial Endosymbiont of the Slender Pigeon Louse, Columbicola columbae, Allied to Endosymbionts of Grain Weevils and Tsetse Flies▿

    PubMed Central

    Fukatsu, Takema; Koga, Ryuichi; Smith, Wendy A.; Tanaka, Kohjiiro; Nikoh, Naruo; Sasaki-Fukatsu, Kayoko; Yoshizawa, Kazunori; Dale, Colin; Clayton, Dale H.

    2007-01-01

    The current study focuses on a symbiotic bacterium found in the slender pigeon louse, Columbicola columbae (Insecta: Phthiraptera). Molecular phylogenetic analyses indicated that the symbiont belongs to the gamma subdivision of the class Proteobacteria and is allied to Sodalis glossinidius, the secondary symbiont of tsetse flies (Glossina spp.) and also to the primary symbiont of grain weevils (Sitophilus spp.). Relative-rate tests revealed that the symbiont of C. columbae exhibits accelerated molecular evolution in comparison with the tsetse fly symbiont and the weevil symbiont. Whole-mount in situ hybridization was used to localize the symbiont and determine infection dynamics during host development. In first- and second-instar nymphs, the symbionts were localized in the cytoplasm of oval bacteriocytes that formed small aggregates on both sides of the body cavity. In third-instar nymphs, the bacteriocytes migrated to the central body and were finally located in the anterior region of the lateral oviducts, forming conspicuous tissue formations called ovarial ampullae. In adult females, the symbionts were transmitted from the ovarial ampullae to developing oocytes in the ovarioles. In adult males, the bacteriocytes often disappeared without migration. A diagnostic PCR survey of insects collected from Japan, the United States, Australia, and Argentina detected 96.5% (109/113) infection, with a few uninfected male insects. This study provides the first microbial characterization of a bacteriocyte-associated symbiont from a chewing louse. Possible biological roles of the symbiont are discussed in relation to the host nutritional physiology associated with the feather-feeding lifestyle. PMID:17766458

  17. First Case of Ascaris lumbricoides Infestation Complicated with Hemophagocytic Lymphohistiocytosis.

    PubMed

    Bayhan, Gülsüm İclal; Çenesiz, Funda; Tanır, Gönül; Taylan Özkan, Ayşegül; Çınar, Gökçe

    2015-06-01

    Ascariasis is a common soil-transmitted helminth infestation worldwide. Ascaris lumbricoides infestation is generally asymptomatic or cause nonspecific signs and symptoms. We report a 5-year-old male with hemophagocytic lymphohistiocytosis associated with A. lumbricoides infestation. The presented patient recovered completely after defecating an A. lumbricoides following intravenous immunoglobulin (IVIG) and mebendazole treatment. We wanted to emphasize that because helminth infestation is easily overlooked, the diagnosis of ascariasis should be considered in patients who live in endemic areas and treated timely to prevent severe complications. PMID:26081893

  18. Hookworm infestation as unexpected cause of recurrent pancreatitis.

    PubMed

    Tseng, Li-Ming; Sun, Cheuk-Kay; Wang, Tzong-Luen; Lin, Aming Chor-Ming

    2014-11-01

    Parasite infestation is still associated with significant morbidity and mortality. Hookworm infestation is a very rare cause of pancreatitis. This parasitic infestation might be asymptomatic. Acute pancreatitis as a result of the hookworms migrating into the ampulla of Vater with chronic inflammation was a very rare complication. Were port a case of hookworm infestation that was associated with significant complication of recurrent pancreatitis. The patient was treated with mebendazole. He was asymptomatic and had gained weight at the 3-month follow-up. Our case demonstrates that pancreatitis secondary to hookworm infection can occur and may resolve after anthelmintic treatment. PMID:24768664

  19. 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,…

  20. Ticks infesting humans in Northern Misiones, Argentina.

    PubMed

    Lamattina, Daniela; Nava, Santiago

    2016-01-01

    This work presents records of ticks infesting humans in northern Misiones Province, Argentina. Also, notes on potential transmission of tick-borne pathogens are included. A total of 282 ticks attached to researchers were collected and identified by their morphological characters. Eight tick species were found: Amblyomma brasiliense, Amblyomma coelebs, Amblyomma dubitatum, Amblyomma incisum, Amblyomma ovale, Haemaphysalis juxtakochi, Rhipicephalus sanguineus and Rhipicephalus microplus. Some of these species as A. dubitatum, A. ovale and R. sanguineus have been found infected with spotted fever group rickettsiae pathogenic to humans in Brazil and Argentina. The potential role as vectors of humans pathogens of the ticks found attached to humans in this study is discussed. PMID:27135846

  1. [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

  2. Parasitic Infestation and Choice of Reproductive Regimes

    NASA Astrophysics Data System (ADS)

    Sousa, A. O.; de Oliveira, S. Moss; Sá Martins, J. S.

    The Penna model is used to simulate the competition between an asexual parthenogenetic and asexual population inhabiting the same environment represented by a square lattice. With a small probability, a newborn from the sexual population mutates into an asexual one and vice versa. Then, the asexual population rapidly dominates the sexual one, which all but disappears. However, when an infestation by mutating genetically coupled parasites, that mimic trematodes that feed on gonads, is introduced, the outcome may be one in which both populations coevolve or one in which one of the populations overcomes the other, depending on the density of parasites on the lattice.

  3. Impregnated netting slows infestation by Triatoma infestans.

    PubMed

    Levy, Michael Z; Quíspe-Machaca, Victor R; Ylla-Velasquez, Jose L; Waller, Lance A; Richards, Jean M; Rath, Bruno; Borrini-Mayori, Katty; del Carpio, Juan G Cornejo; Cordova-Benzaquen, Eleazar; McKenzie, F Ellis; Wirtz, Robert A; Maguire, James H; Gilman, Robert H; Bern, Caryn

    2008-10-01

    We used sentinel animal enclosures to measure the rate of infestation by the Chagas disease vector, Triatoma infestans, in an urban community of Arequipa, Peru, and to evaluate the effect of deltamethrin-impregnated netting on that rate. Impregnated netting decreased the rate of infestation of sentinel enclosures (rate ratio, 0.23; 95% confidence interval, 0.13-0.38; P < 0.001), controlling for the density of surrounding vector populations and the distance of these to the sentinel enclosures. Most migrant insects were early-stage nymphs, which are less likely to carry the parasitic agent of Chagas disease, Trypanosoma cruzi. Spread of the vector in the city therefore likely precedes spread of the parasite. Netting was particularly effective against adult insects and late-stage nymphs; taking into account population structure, netting decreased the reproductive value of migrant populations from 443.6 to 40.5. Impregnated netting can slow the spread of T. infestans and is a potentially valuable tool in the control of Chagas disease. PMID:18840739

  4. Impregnated Netting Slows Infestation by Triatoma infestans

    PubMed Central

    Levy, Michael Z.; Quíspe-Machaca, Victor R.; Ylla-Velasquez, Jose L.; Waller, Lance A.; Richards, Jean M.; Rath, Bruno; Borrini-Mayori, Katty; del Carpio, Juan G. Cornejo; Cordova-Benzaquen, Eleazar; McKenzie, F. Ellis; Wirtz, Robert A.; Maguire, James H.; Gilman, Robert H.; Bern, Caryn

    2008-01-01

    We used sentinel animal enclosures to measure the rate of infestation by the Chagas disease vector, Triatoma infestans, in an urban community of Arequipa, Peru, and to evaluate the effect of deltamethrin-impregnated netting on that rate. Impregnated netting decreased the rate of infestation of sentinel enclosures (rate ratio, 0.23; 95% confidence interval, 0.13–0.38; P < 0.001), controlling for the density of surrounding vector populations and the distance of these to the sentinel enclosures. Most migrant insects were early-stage nymphs, which are less likely to carry the parasitic agent of Chagas disease, Trypanosoma cruzi. Spread of the vector in the city therefore likely precedes spread of the parasite. Netting was particularly effective against adult insects and late-stage nymphs; taking into account population structure, netting decreased the reproductive value of migrant populations from 443.6 to 40.5. Impregnated netting can slow the spread of T. infestans and is a potentially valuable tool in the control of Chagas disease. PMID:18840739

  5. Delusional infestation: an Australian multicentre study of 23 consecutive cases.

    PubMed

    Tran, M M A; Iredell, J R; Packham, D R; O'Sullivan, M V N; Hudson, B J

    2015-04-01

    Delusional infestation remains a debilitating condition that is therapeutically challenging for clinicians. This case series identifies 23 patients with delusional infestation in an Australian setting. The majority of patients are women and unlikely to have a psychiatric comorbid background. The use of unnecessary anti-parasitic medication is prevalent. PMID:25827513

  6. Aboveground insect infestation attenuates belowground Agrobacterium-mediated genetic transformation.

    PubMed

    Song, Geun Cheol; Lee, Soohyun; Hong, Jaehwa; Choi, Hye Kyung; Hong, Gun Hyong; Bae, Dong-Won; Mysore, Kirankumar S; Park, Yong-Soon; Ryu, Choong-Min

    2015-07-01

    Agrobacterium tumefaciens causes crown gall disease. Although Agrobacterium can be popularly used for genetic engineering, the influence of aboveground insect infestation on Agrobacterium induced gall formation has not been investigated. Nicotiana benthamiana leaves were exposed to a sucking insect (whitefly) infestation and benzothiadiazole (BTH) for 7 d, and these exposed plants were inoculated with a tumorigenic Agrobacterium strain. We evaluated, both in planta and in vitro, how whitefly infestation affects crown gall disease. Whitefly-infested plants exhibited at least a two-fold reduction in gall formation on both stem and crown root. Silencing of isochorismate synthase 1 (ICS1), required for salicylic acid (SA) synthesis, compromised gall formation indicating an involvement of SA in whitefly-derived plant defence against Agrobacterium. Endogenous SA content was augmented in whitefly-infested plants upon Agrobacterium inoculation. In addition, SA concentration was three times higher in root exudates from whitefly-infested plants. As a consequence, Agrobacterium-mediated transformation of roots of whitefly-infested plants was clearly inhibited when compared to control plants. These results suggest that aboveground whitefly infestation elicits systemic defence responses throughout the plant. Our findings provide new insights into insect-mediated leaf-root intra-communication and a framework to understand interactions between three organisms: whitefly, N. benthamiana and Agrobacterium. PMID:25676198

  7. Postharvest quarantine treatments for Diaphorina citri on infested curry leaves

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Studies were conducted to evaluate treatments that reduce survival and attachment of Diaphorina citri nymphs on infested curry leaves (Bergera koenigii). Decontamination of curry leaves infested with D. citri in relation to disinfectant (none or Pro-San), temperature (0, 40, and 50°C), and treatment...

  8. Louse-borne relapsing fever (Borrelia recurrentis) diagnosed in 15 refugees from northeast Africa: epidemiology and preventive control measures, Bavaria, Germany, July to October 2015.

    PubMed

    Hoch, Martin; Wieser, Andreas; Löscher, Thomas; Margos, Gabriele; Pürner, Friedrich; Zühl, Jürgen; Seilmaier, Michael; Balzer, Lukas; Guggemos, Wolfgang; Rack-Hoch, Anita; von Both, Ulrich; Hauptvogel, Katja; Schönberger, Katharina; Hautmann, Wolfgang; Sing, Andreas; Fingerle, Volker

    2015-01-01

    We report 15 imported louse-borne relapsing fever (LBRF) cases in refugees in Bavaria, Germany. One patient died. Epidemiological findings confirmed that all were young males from the Horn of Africa (12 from Somalia), who had similar migration routes converging in Sudan continuing through Libya and Italy. The majority likely acquired their infection during migration. Healthcare workers should be aware of LBRF in refugees passing through north Africa to ensure correct treatment and preventive measures. PMID:26538532

  9. The mitochondrial genome of the screamer louse Bothriometopus (phthiraptera: ischnocera): effects of extensive gene rearrangements on the evolution of the genome.

    PubMed

    Cameron, Stephen L; Johnson, Kevin P; Whiting, Michael F

    2007-11-01

    Mitochondrial (mt) genome rearrangement has generally been studied with respect to the phenomenon itself, focusing on their phylogenetic distribution and causal mechanisms. Rearrangements have additional significance through effects on substitution, transcription, and mRNA processing. Lice are an ideal group in which to study the interactions between rearrangements and these factors due to the heightened rearrangement rate within this group. The entire mt genome of the screamer louse Bothriometopus was sequenced and compared to previously sequenced louse genomes. The mt genome is 15,564 bp, circular, and all genes are encoded on the same strand. The gene arrangement differs radically from both other louse species and the ancestral insect. Nucleotide composition is A+T biased, but there is no skew which may be due to reversal of replication direction or a transcriptional effect. Bothriometopus has both tRNA duplication and concerted evolution which has not been observed previously. Eleven of the 13 protein-coding genes have 3' end stem-loop structures which may allow mRNA processing without flanking tRNAs and so facilitate gene rearrangements. There are five candidate control regions capable of forming stem-loop structures. Two are structurally more similar to the control regions of other insect species than those of other lice. Analyses of Bothriometopus demonstrate that louse mt genomes, in addition to being extensively rearranged, differ significantly from most insect species in nucleotide composition biases, tRNA evolution, protein-coding gene structures and putative signaling sites such as the control region. These may be either a cause or a consequence of gene rearrangements. PMID:17925995

  10. First record of a louse fly, Stilbometopa impressa (Bigot), and new host for Microlynchia pusilla (Speiser) (Hippoboscidae) from the Cape Region, Baja California Sur, México.

    PubMed

    Llinas, J; Jiménez, M L

    1996-04-01

    Nine of thirty California quail (Callipepla californica achrustera) captured in autumn of 1992, 17 km west of La Paz, Baja California Sur, México, were parasitized by louse flies. We identified eight Microlynchia pusilla and three Stilbometopa impressa from 30 quails in the ratio of 2.75:1. These are the first records of S. impressa for Cape Region and the first time either fly has been reported from the California quail in Baja California Sur. PMID:8722274

  11. Re: Treatment of Parasitic Skin Diseases with Dimeticones A New Family of Compounds with a Purely Physical Mode of Action

    PubMed Central

    2015-01-01

    The article on use of dimeticone for treatment of epidermal parasitic skin diseases is potentially confusing and misleading because, in a practical sense, only head louse infestation can be treated with this material. Scabies mites are unaffected by silicones and use of dimeticone against other ectoparasites may have unwanted side effects such as anaphylactiform reactions or increased risk of pathogen transmission. PMID:26060419

  12. 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

  13. Ticks infesting bats (Mammalia: Chiroptera) in the Brazilian Pantanal.

    PubMed

    Muñoz-Leal, Sebastián; Eriksson, Alan; Santos, Carolina Ferreira; Fischer, Erich; de Almeida, Juliana Cardoso; Luz, Hermes R; Labruna, Marcelo B

    2016-05-01

    Ticks associated with bats have been poorly documented in the Neotropical Zoogeographical Region. In this study, a total of 1028 bats were sampled for tick infestations in the southern portion of the Brazilian Pantanal. A total of 368 ticks, morphologically identified as Ornithodoros hasei (n = 364) and O. mimon (n = 4), were collected from the following bat species: Artibeus planirostris, Platyrrhinus lineatus, Phyllostomus hastatus, Mimon crenulatum and Noctilio albiventris. Morphological identification of O. hasei was confirmed by molecular analysis. Regarding the most abundant bat species, only 40 (6.2 %) out of 650 A. planirostris were infested by O. hasei, with a mean intensity of 7.2 ticks per infested bat, or a mean abundance of 0.44 ticks per sampled bat. Noteworthy, one single P. hastatus was infested by 55 O. hasei larvae, in contrast to the 2.5-7.2 range of mean intensity values for the whole study. As a complement to the present study, a total of 8 museum bat specimens (6 Noctilio albiventris and 2 N. leporinus), collected in the northern region of Pantanal, were examined for tick infestations. These bats contained 176 ticks, which were all morphologically identified as O. hasei larvae. Mean intensity of infestation was 22, with a range of 1-46 ticks per infested bat. Our results suggest that A. planirostris might play an important role in the natural life cycle of O. hasei in the Pantanal. PMID:26912332

  14. Zebra mussel infestation of unionid bivalves (Unionidae) in North America

    USGS Publications Warehouse

    Schloesser, Don W.; Nalepa, Thomas F.; Mackie, Gerald L.

    1996-01-01

    In 1989, zebra mussels received national attention in North America when they reached densities exceeding 750,000/m2 in a water withdrawal facility along the shore of western Lake Erie of the Laurentian Great Lakes. Although water withdrawal problems caused by zebra mussels have been of immediate concern, ecological impacts attributed to mussels are likely to be the more important long-term issue for surface waters in North America. To date, the epizoic colonization (i.e., infestation) of unionid bivalve mollusks by zebra mussels has caused the most direct and severe ecological impact. Infestation of and resulting impacts caused by zebra mussels on unionids in the Great Lakes began in 1988. By 1990, mortality of unionids was occurring at some locations; by 1991, extant populations of unionids in western Lake Erie were nearly extirpated; by 1992, unionid populations in the southern half of Lake St. Clair were extirpated; by 1993, unionids in widely separated geographic areas of the Great Lakes and the Mississippi River showed high mortality due to mussel infestation. All infested unionid species in the Great Lakes (23) have become infested and exhibited mortality within two to four years after heavy infestation began. Data indicate that mean zebra mussel densities >5,000–6,000/m2 and infestation intensities >100-200/unionid in the presence of heavy zebra mussel recruitment results in near total mortality of unionids. At present, all unionid species in rivers, streams, and akes that sympatrically occur with zebra mussels have been infested and, in many locations, negatively impacted by zebra mussels. We do not know the potential consequences of infestation on the 297 unionid species found in North America, but believe zebra mussels pose an immediate threat to the abundance and diversity of unionids.

  15. Leech (Hirudinea) infestations among waterfowl near Yellowknife, Northwest Territories

    USGS Publications Warehouse

    Bartonek, J.C.; Trauger, D.L.

    1975-01-01

    Fourteen species of aquatic birds, including 11 species of ducks, were infested with leeches Theromyzon rude and Placobdella ornata near Yellowknife, Northwest Territories. Leeches infested 88% of 41 American Wigeon (Anas americana) and 31% of 86 Lesser Scaup (Aythya affinis) examined after death. Lesser Scaup captured by drive-trapping contained significantly more leeches than undisturbed ducks. Leeches were attached to the host within the mucosa of the nasal chamber, to the conjunctiva of the eye and on the skin of the body. Although only two deaths of ducklings were directly attributed to leech infestations, other birds probably died as a result of parasitism by leeches.

  16. Head injury.

    PubMed

    Hureibi, K A; McLatchie, G R

    2010-05-01

    Head injury is one of the commonest injuries in sport. Most are mild but some can have serious outcomes. Sports medicine doctors should be able to recognise the clinical features and evaluate athletes with head injury. It is necessary during field assessment to recognise signs and symptoms that help in assessing the severity of injury and making a decision to return-to-play. Prevention of primary head injury should be the aim. This includes protective equipment like helmets and possible rule changes. PMID:20533694

  17. 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…

  18. Increasing transcriptome response of serpins during the ontogenetic stages in the salmon louse Caligus rogercresseyi (Copepoda: Caligidae).

    PubMed

    Maldonado-Aguayo, W; Gallardo-Escárate, C

    2014-06-01

    Serine protease inhibitors, or serpins, target serine proteases, and are important regulators of intra- and extracellular proteolysis. For parasite survival, parasite-derived protease inhibitors have been suggested to play essential roles in evading the host's immune system and protecting against exogenous host proteases. The aim of this work was to identify serpins via high throughput transcriptome sequencing and elucidate their potential functions during the lifecycle of the salmon louse Caligus rogercresseyi. Eleven putative, partial serpin sequences in the C. rogercresseyi transcriptome were identified and denoted as Cr-serpins 1 to 11. Comparative analysis of the deduced serpin-like amino acid sequences revealed a highly conserved reactive center loop region. Interestingly, P1 residues suggest putative functions involved with the trypsin/subtilisin, elastase, or subtilisin inhibitors, which evidenced increasing gene expression profiles from the copepodid to adult stage in C. rogercresseyi. Concerning this, Cr-serpin 10 was mainly expressed in the copepodid stage, while Cr-serpins 3, 4, 5, and 11 were mostly expressed in chalimus and adult stages. These results suggest that serpins could be involved in evading the immune response of the host fish. The identification of these serpins furthers the understanding of the immune system in this important ectoparasite species. PMID:24798872

  19. Unlocking the black box of feather louse diversity: A molecular phylogeny of the hyper-diverse genus Brueelia.

    PubMed

    Bush, Sarah E; Weckstein, Jason D; Gustafsson, Daniel R; Allen, Julie; DiBlasi, Emily; Shreve, Scott M; Boldt, Rachel; Skeen, Heather R; Johnson, Kevin P

    2016-01-01

    Songbirds host one of the largest, and most poorly understood, groups of lice: the Brueelia-complex. The Brueelia-complex contains nearly one-tenth of all known louse species (Phthiraptera), and the genus Brueelia has over 300 species. To date, revisions have been confounded by extreme morphological variation, convergent evolution, and periodic movement of lice between unrelated hosts. Here we use Bayesian inference based on mitochondrial (COI) and nuclear (EF-1α) gene fragments to analyze the phylogenetic relationships among 333 individuals within the Brueelia-complex. We show that the genus Brueelia, as it is currently recognized, is paraphyletic. Many well-supported and morphologically unified clades within our phylogenetic reconstruction of Brueelia were previously described as genera. These genera should be recognized, and the erection of several new genera should be explored. We show that four distinct ecomorphs have evolved repeatedly within the Brueelia-complex, mirroring the evolutionary history of feather-lice across the entire order. We show that lice in the Brueelia-complex, with some notable exceptions, are extremely host specific and that the host family associations and geographic distributions of these lice are significantly correlated with our understanding of their phylogenetic history. Several ecological phenomena, including phoresis, may be responsible for the macroevolutionary patterns in this diverse group. PMID:26455895

  20. Host selection by the Louse Fly Crataerina pallida, an avian nest ectoparasite of the Common Swift Apus apus.

    PubMed

    Walker, Mark D; Rotherham, Ian D

    2011-09-01

    Preferences by parasites for particular hosts may have important implications for the functioning of host-parasite systems, however, this parasitic life-history trait remains little studied. No detrimental effect of Louse Fly Crataerina pallida parasitism has been found on Common Swift Apus apus nestling hosts. Host selection choices may be mediating the effect this parasite has and account for this apparent avirulence. Two aspects of parasite host selection were studied at a breeding colony of Common Swifts during 2008; (1) intra-brood differences in C. pallida parasitism were studied to determine the influence of nestling rank, (2) differences in male and female C. pallida parasitism were investigated, as they may result in varying costs of parasitism to hosts. C. pallida populations were found to preferentially parasitize higher rather than lower ranking nestlings within broods of both two and three chicks. Greater proportions of females were seen upon nestlings than at the nest, and upon higher ranking than lower ranking nestlings within broods. These results indicate that host selection occurs and this may thus account for the lack of parasitic virulence reported within this host-parasite system. PMID:21641904

  1. MicroRNA biogenesis pathway from the salmon louse (Caligus rogercresseyi): emerging role in delousing drug response.

    PubMed

    Valenzuela-Miranda, Diego; Nuñez-Acuña, Gustavo; Valenzuela-Muñoz, Valentina; Asgari, Sassan; Gallardo-Escárate, Cristian

    2015-01-25

    Despite the increasing evidence of the importance of microRNAs (miRNAs) in the regulation of multiple biological processes, the molecular bases supporting this regulation are still barely understood in crustaceans. Therefore, the molecular characterization and transcriptome modulation of the miRNA biogenesis pathway were evaluated in the salmon louse Caligus rogercresseyi, an ectoparasite that constitutes one of the biggest concerns for salmonid aquaculture industry. Hence, RNA-Seq analysis was conducted from six different developmental stages, and also after bioassays with delousing drugs Deltamethrin and Azamethiphos using adult individuals. In silico analysis evidenced 24 putative genes involved in the miRNA pathway such as biogenesis, transport, maturation and miRNA-target interaction. Moreover, 243 putative single nucleotide polymorphisms (SNPs) were identified, 15 of which showed non-synonym mutations. RNA-Seq analysis revealed that CCR4-Not complex subunit 3 (CNOT3) was upregulated at earlier developmental stages (nauplius I-II and copepodid), and also after the exposure to Azamethiphos, but not to Deltamethrin. In contrast, the subunit 7 (CNOT7) showed an inverse expression pattern. Different Argonaute transcripts were associated to chalimus and adult stages, revealing specific expression patterns in response to antiparasitic drugs. Our results suggest novel insights into the regulatory network of the post-transcriptional gene regulation in C. rogercresseyi mediated by miRNAs, evidencing a putative role during the ontogeny and drug response. PMID:25447902

  2. Decreased detoxification genes and genome size make the human body louse an efficient model to study xenobiotic metabolism

    PubMed Central

    Lee, Si Hyeock; Kang, Jae Soon; Min, Jee Sun; Yoon, Kyong Sup; Strycharz, Joseph P.; Johnson, Reed; Mittapalli, Omprakash; Margam, Venu M.; Sun, Weilin; Li, Hong-Mei; Xie, Jun; Wu, Jing; Kirkness, Ewen F.; Berenbaum, May R.; Pittendrigh, Barry R.; Clark, J. Marshall

    2010-01-01

    The human body louse, Pediculus humanus humanus, has one of the smallest insect genomes, containing ~10,775 annotated genes (Kirkness et al. 2010). Annotation of detoxification [cytochrome P450 monooxygenase (P450), glutathione-S-transferase (GST), esterase (Est), and ATP-binding cassette transporter (ABC transporter)] genes revealed that they are dramatically reduced in P. h. humanus compared to other insects except for Apis mellifera. There are 37 P450, 13 GST and 17 Est genes present in P. h. humanus, approximately half of that found in Drosophila melanogaster and Anopheles gambiae. The number of putatively functional ABC transporter genes in P. h. humanus and A. mellifera are the same (36) but both have fewer than An. gambiae (44) or D. melanogaster (65). The reduction of detoxification genes in P. h. humanus may be due to their simple life history, where they do not encounter a wide variety of xenobiotics. Neuronal component genes are highly conserved across different insect species as expected due to their critical function. Although reduced in number, P. h. humanus still retains at least a minimum repertoire of genes known to confer metabolic or toxicokinetic resistance to xenobiotics (e.g., Cyp3 clade P450s, Delta GSTs, B clade Ests and B/C subfamily ABC transporters), suggestive of its high potential for resistance development. PMID:20561088

  3. Head Injuries

    MedlinePlus

    ... before. Often, the injury is minor because your skull is hard and it protects your brain. But ... injuries can be more severe, such as a skull fracture, concussion, or traumatic brain injury. Head injuries ...

  4. Head Noises.

    ERIC Educational Resources Information Center

    Senior, Tom

    2000-01-01

    Explains how a toy called "Sound Bites" can be modified to demonstrate the transmission of sound waves. Students can hear music from the toy when they press it against any bone in their heads or shoulders. (WRM)

  5. Head Injuries

    MedlinePlus

    ... before. Usually, the injury is minor because your skull is hard and it protects your brain. But ... injuries can be more severe, such as a skull fracture, concussion, or traumatic brain injury. Head injuries ...

  6. An outbreak of Trixacarus caviae infestation in guinea pigs at an animal petting facility and an evaluation of the safety and suitable dose of selamectin treatment.

    PubMed

    Honda, M; Namikawa, K; Hirata, H; Neo, S; Maruo, T; Lynch, J; Chida, A; Morita, T

    2011-08-01

    In June 2009, 27 guinea pigs kept at an animal petting facility at a zoo in Kanagawa Prefecture, Japan, were observed to scratch intensely, weaken, and develop lesions. Three sarcoptiform mites were found in skin scrapings taken from affected areas of 2 guinea pigs, and they were identified as Trixacarus caviae by morphological examination. This result confirmed the presence of T. caviae in Japan. For treatment, doses of 13.6-18.75 mg/head of selamectin were administered in a topical preparation applied to a single spot on the skin on the back of the neck, and no side effects were observed. In April 2010, a second outbreak of mange occurred at the zoo, and, following investigation, 2 mite eggs were observed. It was, therefore, thought probable that the mites had survived during the winter within nonclinical carriers. Accordingly, doses of 5.0-7.5 mg/head of selamectin were applied on days 0 and 28, after which clinical symptoms disappeared and general condition improved. This dose of selamectin was thus shown to be a suitable and economical treatment for guinea pigs infested with the mites. Because the mite is not always easily observed in infested guinea pigs and the potential for human infestation exists, clinicians should not hesitate to treat when the clinical presentation suggests infestation, particularly in a setting such as an animal petting facility, where large numbers of children and adults have direct contact with the animals. PMID:21506831

  7. Intestinal Infestations in Under-Five Children in Zambia

    PubMed Central

    Mwale, Kamukwamba; Siziya, Seter

    2015-01-01

    Background: Intestinal infestations are of considerable public health importance in Zambia and elsewhere in Africa. Children aged less than 5 years are at the highest risk of infection. Interventions for prevention and control of these infestations require identification of their determinants. This study investigates the determinants of intestinal infestations in children below 5 years of age admitted to a children’s hospital and assesses the most prevalent of the helminthes. Methods: This was a hospital based cross-sectional study conducted at Arthur Davison Children’s Hospital, Ndola, Zambia. Socio-demographic data of study participants and possible determinants for occurrence of intestinal infestations were collected using structured questionnaires. Stool samples were collected and examined for presence of parasites using direct techniques. The Pearson’s Chi-square and Fisher’s exact tests were used to establish associations. Results: Present study had 148 participants out of the expected 165, making a respondent rate of 89.7%. Over half of the participants were male (50.6%), and 68.9% were above the age of 2 years. Prevalence of intestinal infestations was 19.6%, and the most prevalent parasite was Ascaris lumbricoides. Factors independently associated with worm infestation were father’s employment (AOR = 0.41; 95 % CI [0.19, 0.90]) and history of prior worm infestation (AOR = 6.54; 95 % CI [3.28, 13.03]). Conclusion: Intestinal infestations particularly Ascaris lumbricoides were more prevalent in this study. There should be policy towards countrywide deworming programs and enhanced hygiene.

  8. Cat Flea Infestation in a Hospital: A Case Report

    PubMed Central

    Norhayati, Moktar; Lee, Yin Yin

    2012-01-01

    Cat flea bite in humans results in extremely pruritic skin lesions. It has been reported to occur among those living in domiciliary accommodation. However, nosocomial infestation with cat flea has not been reported. We hereby report a case of nosocomial infestation of cat flea in a hospital facility. Identification of the parasite, its appropriate eradication, and adequate medical management of the patients resulted in a satisfactory outcome. PMID:22451739

  9. Effect of households' social networks on lice infestation among vulnerable Mexican children: a qualitative comparative analysis.

    PubMed

    Ortega-Marín, Lydia; Márquez-Serrano, Margarita; Lara-López, Luz M; Moncada, Ligia I; Idrovo, Alvaro J

    2013-10-01

    The prevalence of pediculosis is high among elementary and secondary school children, which favors the belief that infestation occurs more often in schools than in homes. This study explored the role of households' social networks in the transmission of head lice. Seventeen school children and their social networks (n = 22) from Acatlipa (Morelos, Mexico) participated in a prospective observational study during school vacation. The hair of all the school children was washed with shampoo containing permethrin at the beginning of the study and the incidence of pediculosis (O) was evaluated at the beginning of the school term (follow-up at 1.5 months). The sets included in the qualitative comparative analysis were sex (S), length of hair (H), baseline diagnostic of pediculosis (I) and degree (D) and infestation index (N) obtained through the analysis of social networks. The prevalence of pediculosis was the same at the beginning and the end of follow-up (17.6%). The degree of the school children's networks ranged between 2 and 14. There were 8 configurations, the most frequent being F*i*d*n*h. The most parsimonious configuration associated with the incidence of pediculosis was F*I*d*H (female, previous infestation, low degree and long hair), with a coverage of 0.344 and a consistency of 0.941. Indicators of social networks made it possible to identify the role of households' social networks in the transmission of lice. Individual actions such as the use of shampoo containing insecticides are temporary and, therefore, structural actions should be favored. PMID:23751254

  10. 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

  11. 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

  12. 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

  13. Cone Heads

    ERIC Educational Resources Information Center

    Coy, Mary

    2005-01-01

    The author, a middle school art teacher, describes a sculpture project lesson involving Cone Heads (sculptures made from cardboard cones). Discussion of caricatures with exaggerated facial features and interesting profiles helped students understand that the more expressive the face, the better. This project took approximately four to five…

  14. Control of subterranean termites (Isoptera: Rhinotermitidae) infesting power poles.

    PubMed

    Horwood, Martin A; Westlake, Terry; Kathuria, Amrit

    2010-12-01

    A trial was conducted to determine the efficacy of termiticidal dusts (arsenic trioxide, triflumuron, and Metarhizium anisopliae), a timber fumigant (dazomet) and liquid termiticides (bifenthrin, chlorfenapyr, chlorpyrifos, fipronil, and imidacloprid) for controlling subterranean termites (Isoptera: Rhinotermitidae) infesting in-service power poles in New South Wales, Australia. Dusts were applied to parts of the pole where termites were present. Fumigant was inserted into holes drilled into the base of the pole. Liquid termiticides were mixed with soil around the base of the pole and injected into internal voids if present. Poles were inspected for up to 5 yr, and the time taken for reinfestation to occur was recorded. Before the start of the trial, the major Australian pole owners were surveyed to obtain an estimate of the annual national cost of termite infestation to the power supply industry. The annual costs of termite treatment and replacing damaged poles were estimated at AU$2 million and AU$13 million, respectively. Infestation rates were lower for all treatments compared with controls within the first 12 mo of the study. Dazomet, arsenic trioxide, fipronil, and chlorpyrifos were the most efficacious treatments. Efficacy was positively related to the amount of termiticide applied and negatively related to the infestation severity but was unaffected by geographical location. Survival curves were calculated of the time elapsed before the recurrence of termite infestations (survival absence of reinfestation). Survival was highest for poles treated with liquid termiticides. PMID:21309237

  15. Parasitic Infestation in Pediatric and Adolescent Appendicitis: A Local Experience

    PubMed Central

    Zakaria, Ossama M.; Zakaria, Hazem M.; Daoud, Mohamed Yasser; Al Wadaani, Hamed; Al Buali, Waleed; Al-Mohammed, Hamdan; Al Mulhim, Abdulrahman S.; Zaki, Wafaa

    2013-01-01

    Objective The relationship between parasites and pediatric appendicitis is a highly debatable issue. This study aims to investigate the role of parasitic infestation in the etiology of acute pediatric appendicitis. Methods A retrospective study including 1600 pediatric and adolescent patients who had undergone surgical therapy for a diagnosis of acute appendicitis over a period of ten years from Jan 2001 to Dec 2010. Demographic data were retrieved including the patient's age, sex, clinical data, clinical presentations, laboratory investigations, operative data and pathological findings to identify the presence and type of parasites. Patients were divided into two groups according to the presence or absence of parasites in the appendix lumen. In group I (n: 88), parasitic infestation was observed, whereas in group II (n: 1502), no parasitic infestation was present. Results Parasites were present in 5.5% (88 patients), and of those 88 parasitic infestations, 45 (51.1%) were Enterobaisis, 8 (9.1%) were Schistosomiasis, 23 (26.1%) were Ascariasis, 7 (8%) Trichuriasis, and 5 (5.7%) were Teania Saginata. The percentage of patients with suppurative, gangrenous or perforated appendicitis was similar in both groups with no statistical significance, irrespective of the presence or absence of parasitic infestation. Conclusion The low prevalence of parasites among the appendectomy specimens did not support the notion that parasites were a major cause of appendicitis in pediatric patients. PMID:23599875

  16. Some Practical Considerations in the Control of Louse-borne Typhus Fever in Great Britain in the Light of Experience in Russia, Poland, Rumania and China

    PubMed Central

    Mackenzie, Melville D.

    1941-01-01

    This paper deals with some aspects of the control of louse-borne typhus fever. The epidemic form is associated with famine and overcrowding. In producing an epidemic in a hitherto endemic area malnutrition is of greater importance than over-crowding; another factor which brings this about is widespread movement of civil or military population thus bringing non-immunes into a district where typhus is endemic. Endemic typhus usually occurs in the early months of the year, whilst the epidemic form may appear at any time. Conditions under which epidemic typhus occurs favour the outbreak of other diseases so that an uncomplicated case is rarely seen. Louse-borne typhus fever lasts from twelve to sixteen days. The incubation period is usually twelve to fourteen days, though it may be from five to twenty-one days. The onset is sudden, but is often preceded by malaise and a rise of temperature. Two common initial symptoms are acute frontal or occipital headache and bronchitis. The first sign may be mental confusion or delirium. Acute delirium is usually present after the first week. PMID:19992447

  17. Detecting Weed Infestations in Soybean Using Remote Sensing.

    NASA Astrophysics Data System (ADS)

    Clay, S. A.; Chang, J.; Clay, D. E.; Dalsted, K.; Reese, C.

    2007-12-01

    Can weed distribution maps be developed from remote sensed reflectance data? When are the appropriate times to collect these data during the season? What wavebands can be used to distinguish weedy from weed- free areas? This research examined if and when reflectance could be used to distinguish between weed-free and weed-infested (mixed species) areas in soybean and to determine the most useful wavebands to separate crop, weed, and soil reflectance differences. Treatments in the two-year study included no vegetation (bare soil), weed-free soybean, and weed-infested soybean and, in one year, 80% corn residue cover. Reflectance was measured at several sampling times from May through September in 2001 and 2002 using a hand-held multispectral radiometer equipped with band-limited optical interference filters (460 - 1650 nm). Pixel resolution was 0.8-m. Reflectance in the visible spectral range (460 to 700 nm) generally was similar among treatments. In the near-infrared (NIR) range (>700 to 1650 nm), differences among treatments were observed from soybean growth stage V-3 (about 4 weeks after planting) until mid-July to early August depending on crop vigor and canopy closure (76 cm row spacing in 2001 and 19 cm row spacing in 2002). Reflectance rankings in the NIR range when treatments could be differentiated were consistent between years and, from lowest to highest reflectance, were soil < weed-free < weed-infested areas. Increased reflectance from weed-infested areas was most likely due to increased biomass and canopy cover. Residue masked differences between weed-free and weed- infested areas during the early stages of growth due to high reflectance from the residue and reduced weed numbers in these areas. These results suggest that NIR spectral reflectance collected prior to canopy closure can be used to distinguish weed-infested from weed-free areas.

  18. 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

  19. Enterobius vermicularis infestation masquerading as cervical carcinoma: A cytological diagnosis.

    PubMed

    Raju, Kalyani; Verappa, Seema; Venkataramappa, Srinivas Murthy

    2015-01-01

    Although prevalence of Enterobius vermicularis (EV) infestation in Intestines ranges from 35% to 70%, its prevalence in female genital tract is not known despite several incidental findings. Acute inflammatory cells in the background of cervical Pap smear indicate infestation and should not be neglected as contamination. A 40-year-woman presented with white vaginal discharge persistent for past 1 year. Local examination showed hypertrophied cervix with eversion of both lips and hard consistency of the anterior lip of cervix. A clinical diagnosis of cervical carcinoma was made. However, cervical Pap smear indicated EV eggs in an inflammatory background, treatment to which resulted in completely recovery. PMID:26283859

  20. Colonic obstruction and perforation related to heavy Trichuris trichiura infestation.

    PubMed Central

    Bahon, J; Poirriez, J; Creusy, C; Edriss, A N; Laget, J P; Dei Cas, E

    1997-01-01

    Heavy Trichuris trichiura infestation is rare in developed countries, and complications requiring surgical intervention have been described rarely in human trichuriasis. A case of colonic obstruction and perforation related to heavy whip-worm infection is described in an 84 year old woman. The woman was admitted to hospital because of a chest infection. Two days after admission she suffered nausea and vomiting followed a day later by bowel stoppage. Laparotomy indicated intestinal obstruction by a tumour. A partial right sided ileocolectomy was performed. Pathological examination of the resected bowel revealed heavy infestation with T trichiura causing a pseudotumour following a proliferative inflammatory response. Images PMID:9306948

  1. Enterobius vermicularis infestation masquerading as cervical carcinoma: A cytological diagnosis

    PubMed Central

    Raju, Kalyani; Verappa, Seema; Venkataramappa, Srinivas Murthy

    2015-01-01

    Although prevalence of Enterobius vermicularis (EV) infestation in Intestines ranges from 35% to 70%, its prevalence in female genital tract is not known despite several incidental findings. Acute inflammatory cells in the background of cervical Pap smear indicate infestation and should not be neglected as contamination. A 40-year-woman presented with white vaginal discharge persistent for past 1 year. Local examination showed hypertrophied cervix with eversion of both lips and hard consistency of the anterior lip of cervix. A clinical diagnosis of cervical carcinoma was made. However, cervical Pap smear indicated EV eggs in an inflammatory background, treatment to which resulted in completely recovery. PMID:26283859

  2. 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

  3. Does the removal of mite-infested brood facilitate grooming?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The relationship between the removal of mite-infested brood and mite drop was compared using Russian (RHB, n = 9) and Italian (IHB, n = 9) honey bee colonies. A cloake board was used to isolate test brood frame on the top hive body and the metal sheet served as a varroa trap. Inoculum mites were col...

  4. Parasitic infestation of lung: An unusual cause of interstitial pneumonitis

    PubMed Central

    Shah, Parth; Kate, Arvind H; Nester, Nora; Patole, Kamlakar; Leuppi, Joerg D; Chhajed, Prashant N

    2016-01-01

    Parasite infections are increasing worldwide due to increasing migration and traveling. Parasitic infections can affect lungs and present as a focal or diffuse lung diseases. High index of suspicion and detailed history are most important. We present a case of interstitial pneumonitis caused by parasite infestation, which was diagnosed on transbronchial lung biopsy. PMID:27051117

  5. Remote sensing for detecting and mapping whitefly (Bemisia tabaci) infestations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Remote sensing technology has long been used for detecting insect infestations on agricultural crops. With recent advances in remote sensing sensors and other spatial information technologies such as Global Position Systems (GPS) and Geographic Information Systems (GIS), remote sensing is finding mo...

  6. Postharvest tillage reduces Downy Brome infestations in winter wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the Pacific Northwest, downy brome continues to infest winter wheat producing regions especially in low-rainfall areas where the winter wheat-summer fallow rotation is the dominate production system. In Washington, a study was conducted for 2 years at each of two locations in the winter wheat -su...

  7. Susceptibility of pear to European pear sawfly fruit infestation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The European pear sawfly, Hoplocampa brevis (Klug), is a relatively new pest in the Mid-Atlantic fruit production region. A plot containing twelve Pyrus communis pear cultivars and one breeder’s selection in a randomized block design was surveyed for fruit damage. Infestation frequency ranged from...

  8. Natural trematode infestation in feral Nebrodi Black pigs: pathological investigations.

    PubMed

    Capucchio, Maria Teresa; Catalano, Deborah; Di Marco, Vincenzo; Russo, Miriam; Aronica, Vincenzo; Tomaselli, Amedeo; Lazzara, Alessandro; Amedeo, Stefano; Scaglione, Frine Eleonora; Dore, Bruno; Guarda, Franco

    2009-01-22

    Few studies describe the parasites of pigs bred in the wild state, although pigs are a known reservoir of trematode infestation. This article reports the results of a retrospective study carried out from January 2003 to June 2007 on 3021 Nebrodi Black male and female pigs, regularly slaughtered, aged between 8 months and 4 years. Fasciola hepatica and Dicrocoelium dendriticum flukes were detected in 143 (4.37%) of 3021 livers. The predominant histological features were multifocal to diffuse chronic hepatitis, with fibrosis and severely thickened walls of the bile ducts and chronic parietal, sometimes nodular inflammation. F. hepatica infestation was frequently associated with marked hyperplasia and hypertrophy of the submucosal glands. The study results confirm the important role swine play in the transmission of trematode infestations, indicate the prevalence of these parasites in the Nebrodi Park area, and draw attention to the need for a prophylaxis plan to prevent the spread of infestation to ruminants and humans living in the area. PMID:19038498

  9. Infestation of grasses by eriophyoid mites (Acari: Eriophyoidea) in Turkey

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Despite the economic importance of eriophyoid mites as agricultural pests, especially of cereal crops, knowledge of the eriophyoid fauna in Turkey remains incomplete. This paper presents the results of a 3-year study on grass-infesting eriophyoid mites in Turkey. The aim of this study was to collect...

  10. Reducing costly zebra mussel infestations at power plants

    SciTech Connect

    Smythe, G.

    1994-10-01

    The fast-spreading-zebra mussel has significant potential to foul intakes and other water systems at North American hydro projects. Chemical controls can be effective in reducing infestations, but most have environmental and other drawbacks. Several non-chemical methods promise to help project operators reduce problems associated with the mussels.

  11. Tropilaelaps mercedesae and Varroa destructor: prevalence and reproduction in concurrently infested Apis mellifera colonies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The prevalence of Tropilaelaps mercedesae and Varroa destructor in concurrently infested A. mellifera colonies in Thailand was monitored. We also assessed the reproductive ability of T. mercedesae and V. destructor in naturally infested brood and in brood cells deliberately infested with both mite g...

  12. 9 CFR 72.12 - Cattle; exposure to tick infestation after treatment or inspection prohibited.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Cattle; exposure to tick infestation... (INCLUDING POULTRY) AND ANIMAL PRODUCTS BOVINE BABESIOSIS § 72.12 Cattle; exposure to tick infestation after treatment or inspection prohibited. The cattle shall not be exposed to tick infestation after treatment...

  13. Determination of degree of infestation of triticale seed using NIR spectroscopy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insect infestation of seeds of the triticale hybrid, Triticosecale, causes extraordinary storage losses as a consequence of vulnerability of triticale seed to insect infestation and its soft coat. Rice weevil, Sitophilus oryzae (L.), is a common insect that causes infestation in Florida, which was t...

  14. 78 FR 24665 - Gypsy Moth Generally Infested Areas; Additions in Wisconsin

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-26

    ... Inspection Service 7 CFR Part 301 Gypsy Moth Generally Infested Areas; Additions in Wisconsin AGENCY: Animal... are amending the gypsy moth regulations by adding areas in Wisconsin to the list of generally infested areas based on the detection of infestations of gypsy moth in those areas. As a result of this...

  15. Russian Honey Bees and Their Response Toward Brood Infested with Small Hive Beetles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    African bees are known to preferentially remove brood that is infested with small hive beetles (SHB). European honey bees (EHB) also remove infested brood but at a lower frequency. The response of different stocks of EHB to brood infested with SHB has not been studied. Therefore, this study was cond...

  16. Russian Honey Bees And Their Response Toward Brood Infested With Small Hive Beetles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    African bees are known to preferentially remove brood that is infested with small hive beetles (SHB). European honey bees (EHB) also remove infested brood but at a lower frequency. The response of different stocks of EHB to brood infested with SHB has not been studied. Therefore, this study was cond...

  17. 9 CFR 95.28 - Hay or straw and similar material from tick-infested areas.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... tick-infested areas. 95.28 Section 95.28 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION... THE UNITED STATES § 95.28 Hay or straw and similar material from tick-infested areas. Hay or straw, grass, or similar material from tick-infested pastures, ranges, or premises may disseminate...

  18. Difference in skin immune responses to infection with salmon louse (Lepeophtheirus salmonis) in Atlantic salmon (Salmo salar L.) of families selected for resistance and susceptibility.

    PubMed

    Holm, Helle; Santi, Nina; Kjøglum, Sissel; Perisic, Nebojsa; Skugor, Stanko; Evensen, Øystein

    2015-02-01

    Atlantic salmon is susceptible to the salmon louse (Lepeophtheirus salmonis) and the variation in susceptibility within the species can be exploited in selective breeding programs for louse resistant fish. In this study, lice counts were completed on 3000 siblings from 150 families of Atlantic salmon identified as high resistant (HR) and low resistant (LR) families in two independent challenge trials. Skin samples behind the dorsal fin (nearby lice attachment) were collected from ten extreme families (HR or LR) and analyzed by qPCR for the expression of 32 selected genes, including a number of genes involved in T helper cell (Th) mediated immune responses, which have been previously implied to play important roles during salmon louse infections. Most genes showed lower expression patterns in the LR than in HR fish, suggesting an immunosuppressed state in LR families. The average number of lice (chalimi) was 9 in HR and 15 in LR fish. Large variation in lice counts was seen both within resistant and susceptible families, which enabled us to subdivide the groups into HR < 10 and HR > 10, and LR < 10 and LR > 10 to better understand the effect of lice burden per se. As expected, expression patterns were influenced both by genetic background and the number of attached parasites. Higher number of lice (>10) negatively affected gene expression in both HR and LR families. In general, strongest down-regulation was seen in LR > 10 and lesser down-regulation in HR < 10. HR in general and especially HR < 10 fish were better at resisting suppression of expression of both Th1 and Th2 genes. However, the best inverse correlation with infection level was seen for the prototypical Th1 genes, including several members from the interferon pathways. In addition, skin histomorphometry suggests that infected LR salmon had thicker epidermis in the area behind the dorsal fin and larger mucous cell size compared to infected HR fish, however marginally significant (p = 0.08). This

  19. 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

  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. Geographical characterization of the triatomine infestations in north-central Guatemala.

    PubMed

    Nakagawa, J; Juárez, J; Nakatsuji, K; Akiyama, T; Hernandez, G; Macal, R; Flores, C; Ortiz, M; Marroquín, L; Bamba, T; Wakai, S

    2005-04-01

    In an entomological study in 2002, the degree of domestic and peridomestic infestation with triatomine bugs and the geographical distribution of such infestations were investigated in north-central Guatemala. The survey team searched for triatomines in houses constructed with mud walls or thatched roofs, in villages suspected of being infested. The level of infestation observed was lower than that seen in the same area and in eastern Guatemala, in a preliminary survey, 3 years earlier. Most of the infestations detected were of Triatoma dimidiata but even this species was found in <7% of the houses investigated. Infestations with Rhodnius prolixus or other potential vectors of Trypanosoma cruzi were much rarer. The generally low levels of infestation make the elimination of R. prolixus and the reduction of the domestic population of Tri. dimidiata feasible in the study area. The southern part of the study area had higher levels of domestic infestation and colonization than the north, and peridomestic infestation was highest in the south-west. Given such geographical variation in the pattern of infestation, it would seem wise to stratify the study region into areas of high, moderate and low-risk of human-triatomine contact, so that appropriate vector-control strategies can be targeted at the worst-affected areas. Regular entomological surveillance, ideally with community participation, is recommended. Analysis of the relationship between the geographical patterns of infestation and factors such as vegetation, altitude and vector migration would be useful. PMID:15829138

  2. Aphid infestation affecting the biogeochemistry of European beech saplings

    NASA Astrophysics Data System (ADS)

    Michalzik, B.; Levia, D. F., Jr.; Bischoff, S.; Näthe, K.

    2014-12-01

    Mass outbreaks of herbivore insects are known to perturb the functional properties of forests. However, it is less clear how endemic to moderate aboveground herbivory affects the vertical flow of nutrients from tree canopies to the soil. Here, we report on the effects of low to moderate infestation levels of the woolly beech aphid (Phyllaphis fagi L.) on the nutrient dynamics and hydrology of European beech (Fagus sylvatica L.). In a potted sapling experiment, we followed the vertical dynamics of nutrients via throughfall (TF), stemflow (SF) and litter leachates (LL) collected over ten weeks underneath infested and uninfested control trees. Aphid infestation amplifies the fluxes of K+, Mn2+ and particulate nitrogen (0.45μm < PN < 500 μm) in TF solution by 42% for K+, 59% for Mn2+ and 13% for PN relative to the control. In contrast, fluxes of NH4-N and SO4-S diminished during peaking aphid abundance by 26 and 16%, respectively. Differences in canopy-derived dissolved nitrogen and carbon compounds, sulfur (S), Ca2+, Mg2+, Na+ were < 10%. The effect of aphid abundance on nutrient dynamics was most notable in TF and SF and diminished in LL.Aphid infestation greatly altered the SF fluxes of DOC, K+, Mn2+, DON and sulfur-species, which were significantly concentrated at the tree base by "funneling" the rainfall through the canopy biomass to the trunk. Normalized to one square meter, water and nutrient fluxes were amplified by a factor of up to 200 compared to TF.Imaging of leaf surfaces by scanning electron microscopy exhibited notable differences of the surface morphology and microbiology of control, lightly infested, and heavily infested leaves. This observation might point to an aphid-mediated alteration of the phyllosphere ecology triggering the microbial uptake of NH4-N and SO4-S and its transformation to particulate N by magnified biomass growth of the phyllosphere microflora, consequently changing the chemical partitioning and temporal availability of nitrogen.

  3. Biophoton Emission from Kidney Bean Leaf Infested with Tetranychus Kanzawai Kishida

    NASA Astrophysics Data System (ADS)

    Kawabata, Ryuzou; Uefune, Masayoshi; Miike, Tohru; Okabe, Hirotaka; Takabayashi, Junji; Takagi, Masami; Kai, Shoichi

    2004-08-01

    We studied spontaneous photon emission from kidney bean leaves infested with spider mites. Strong photon radiation was observed from the leaf veins where spider mites were crowding. Photon emission intensity increased with the decreases in chlorophyll content and photosynthesis yield; these decreases represented the degree of damage caused by the pest. When both infested and un-infested leaves were put on the same wet cotton, photon emission from the un-infested leaf increased, too. Photon emission from the un-infested leaf might be induced by an aqueous elicitor released from the infested leaf. Such an elicitor activates the plant defense response. Therefore, it is suggested that photon emission from an infested leaf conveys information on the direct injury (physical stresses) and physiological (biochemical) actions associated with the defensive response.

  4. Infestation of the clam Chione fluctifraga by the burrowing worm Polydora sp. nov. in laboratory conditions.

    PubMed

    Tinoco-Orta, Gissel Dalila; Cáceres-Martínez, Jorge

    2003-07-01

    Burrowing worms that belong to Polydora spp. infest marine mollusks cultured worldwide, causing problems for production and marketing. The clam Chione fluctifraga is semi-cultured in Bahía Falsa, Baja California, NW Mexico, and some clams harbor burrowing worms. The present study was carried out to determine the identity of the worm species infesting the clam, the infesting process by cohabitation of infested and non-infested clams in aquaria with a variety of substrates (fine sand, gross sand, plastic bag used for clam culture, and aquarium without substrate) and turbulence conditions, and the occurrence of architomy phenomena in connection with infestation of the clam. The burrowing worm was considered as a nova species due to its singular limbate neurosetae and notosetae in the setiger 5, hooks in the setiger 6, eyes not present, and general pigmentation, among other characteristics. Infestation was similar in all substrates and turbulence conditions, but it was more abundant on clams previously infested than on those free of worms, showing a preferential settlement of worm infesting stages on pre-infested clams. Regeneration was observed in all segments of the worm: anterior (metastomium), medium, and posterior (prostomium); the complete regeneration time occurred in 40 days. This is the first record of architomy in a species of Polydora and this phenomenon could account for the increase of infestation intensity in pre-infested clams at the end of the study period. Infestation of clams by settling polichaete in the conditions studied, and the architomy process in this worm species, shows its great infesting capacity. PMID:12877826

  5. Negligible Egg Positive Rate of Enterobius vermicularis and No Detection of Head Lice among Orphanage Children in Busan and Ulsan, Korea (2014)

    PubMed Central

    Kim, Dong-Hee; Son, Hyun-Mi; Lee, Sang Hwa; Park, Mi Kyung; Kang, Shin Ae; Park, Sang Kyun; Choi, Jun-Ho; Park, Jung Ha; Yu, Hak-Sun

    2015-01-01

    To determine whether pinworm infections and head lice infestations spread among children in orphanages, 117 children from 4 orphanages in Busan-si and Ulsan-si, Korea, were examined for enterobiasis and head lice infestation between January and February 2014. The overall rate of Enterobius vermicularis egg positivity was 0.85%, whereas none of the children had head lice infestations. The rate of pinworm infection was much lower among the orphanage children compared to the rates observed in previous studies among kindergarten and primary school students. Moreover, the risk factors for enterobiasis were less frequent among these subjects than previously reported. The personal hygiene and health of the orphanage children were supervised by a regular, employed nurse through a health education program. In conclusion, pinworm infection was efficiently controlled among the children in orphanages, and this might be related to good personal hygiene practices in Korea. PMID:26323851

  6. Negligible Egg Positive Rate of Enterobius vermicularis and No Detection of Head Lice among Orphanage Children in Busan and Ulsan, Korea (2014).

    PubMed

    Kim, Dong-Hee; Son, Hyun-Mi; Lee, Sang Hwa; Park, Mi Kyung; Kang, Shin Ae; Park, Sang Kyun; Choi, Jun-Ho; Park, Jung Ha; Yu, Hak-Sun

    2015-08-01

    To determine whether pinworm infections and head lice infestations spread among children in orphanages, 117 children from 4 orphanages in Busan-si and Ulsan-si, Korea, were examined for enterobiasis and head lice infestation between January and February 2014. The overall rate of Enterobius vermicularis egg positivity was 0.85%, whereas none of the children had head lice infestations. The rate of pinworm infection was much lower among the orphanage children compared to the rates observed in previous studies among kindergarten and primary school students. Moreover, the risk factors for enterobiasis were less frequent among these subjects than previously reported. The personal hygiene and health of the orphanage children were supervised by a regular, employed nurse through a health education program. In conclusion, pinworm infection was efficiently controlled among the children in orphanages, and this might be related to good personal hygiene practices in Korea. PMID:26323851

  7. Distribution pattern of phthirapterans infesting certain common Indian birds.

    PubMed

    Saxena, A K; Kumar, Sandeep; Gupta, Nidhi; Mitra, J D; Ali, S A; Srivastava, Roshni

    2007-08-01

    The prevalence and frequency distribution patterns of 10 phthirapteran species infesting house sparrows, Indian parakeets, common mynas, and white breasted kingfishers were recorded in the district of Rampur, India, during 2004-05. The sample mean abundances, mean intensities, range of infestations, variance to mean ratios, values of the exponent of the negative binomial distribution, and the indices of discrepancy were also computed. Frequency distribution patterns of all phthirapteran species were skewed, but the observed frequencies did not correspond to the negative binomial distribution. Thus, adult-nymph ratios varied in different species from 1:0.53 to 1:1.25. Sex ratios of different phthirapteran species ranged from 1:1.10 to 1:1.65 and were female biased. PMID:17918388

  8. Efficient detection of internal infestation in wheat based on biophotonics.

    PubMed

    Shi, Weiya; Jiao, Keke; Liang, Yitao; Wang, Feng

    2016-02-01

    In the process of grain storage, there are many losses of grain quantity and quality for the sake of insects. As a result, it is necessary to find a rapid and economical method for detecting insects in the grain. The paper innovatively proposes a model of detecting internal infestation in wheat by combining pattern recognition and BioPhoton Analytical Technology (BPAT). In this model, the spontaneous ultraweak photons emitted from normal and insect-contaminated wheat are firstly measured respectively. Then, position, distribution and morphological characteristics can be extracted from the measuring data to construct wheat feature vector. Backpropagation (BP) neural network based on genetic algorithm is employed to take decision on whether wheat kernel has contaminated by insects. The experimental results show that the proposed model can differentiate the normal wheat from the insect-contaminated one at an average accuracy of 95%. The model can also offer a novel thought for detecting internal infestation in the wheat. PMID:26774558

  9. Delusional infestation with unusual pathogens: a report of three cases.

    PubMed

    Dewan, P; Miller, J; Musters, C; Taylor, R E; Bewley, A P

    2011-10-01

    Delusional infestation (DI) is a psychiatric disorder characterized by a fixed, false belief that the patient is infested with extracorporeal agents. It is known by several names, including the more commonly used term 'delusional parasitosis'. The psychiatric disease is responsible for the cutaneous pathology. About 90% of patients with DI seek help from dermatologists, and most reject psychiatric referral. Thus, effective management requires incorporation of psychiatric principles. We report three cases of DI with inanimate materials, and examine 'Morgellons' disease. We believe that patients with unusual presentations of DI are likely to be seen more commonly in the future. These patients appear to be a subgroup of DI, and may be even more difficult to treat than other patients with DI. PMID:21933231

  10. Head and face reconstruction

    MedlinePlus

    Head and face reconstruction is surgery to repair or reshape deformities of the head and face (craniofacial). ... How surgery for head and face deformities (craniofacial reconstruction) ... and the person's condition. Surgical repairs involve the ...