@article {96375, title = {First Detection of Acinetobacter baumannii in Pediculus humanus capitis from Latin America}, journal = {Tropical Medicine and Infectious Disease}, volume = {8}, year = {2023}, month = {Jun-29-2023}, pages = {8 pp}, type = {Open Access - Brief report}, abstract = {

Several studies have documented the presence of Acinetobacter baumannii, a known multi-drug-resistant pathogen, in the human head louse, Pediculus humanus capitis. Since no reports from countries in Latin America have been published, the aim of the present study was to determine whether A. baumannii was present in head lice specimens collected in this geographic region. Head lice specimens from Argentina, Colombia, and Honduras were analyzed. PCR assays were performed to confirm the specimens\’ species and to investigate whether the DNA of A. baumannii was present. The products of the latter were sequenced to confirm bacterial identity. Altogether, 122 pools of head lice were analyzed, of which two (1.64\%) were positive for A. baumannii\’s DNA. The positive head lice had been collected at the poorest study site in Honduras. The remaining specimens were negative. This study is the first to report the presence of A. baumannii in human head lice from Latin America. Further investigations are required to elucidate whether these ectoparasites can serve as natural reservoirs or even effectively transmit A. baumannii to humans.

}, keywords = {Acinetobacter baumannii, Argentina, Colombia, head lice, Honduras, Latin America}, issn = {2414-6366}, doi = {10.3390/tropicalmed8070345}, url = {https://www.mdpi.com/2414-6366/8/7/345}, author = {Kelsey Larkin and Toloza,Ariel Ceferino and Jose Antonio Gabrie and Carol Rodr{\'\i}guez and Mar{\'\i}a M. Rueda and Gabriela Matamoros and Oscar Palacio and Shabana Jamani and Gustavo Fontecha and Ana Sanchez} } @article {94633, title = {Insights About Head Lice Transmission From Field Data and Mathematical Modeling}, journal = {Journal of Medical Entomology}, volume = {55}, year = {2018}, pages = {929 - 937}, abstract = {

Head lice infest millions of school-age children every year, both in developed and developing countries. However, little is known about the number of lice transferred among children during school activities, because direct methods to study this are almost impossible to implement. This issue has been addressed following an indirect method, which consist in collecting data of real infestation from several children groups and using a mathematical model of lice colonies to infer how the infestation observed might have evolved. By determining the events that would most likely lead to infestations as those observed, we find that severe infestations are most likely initiated by a relatively large number of lice transferred at the same moment or within relatively short time spans. In turn, analysis of the data obtained from screenings of the same groups of children a few days apart shows evidence of such transmission events. Interestingly, only children with severe infestations could harbor the lice necessary for this type of transmission.Thus, they play the same role as \‘superspreaders\’ in epidemiology. As part of our experimental study it is also shown that a simple procedure of combing can be very effective to remove all mobile lice, and thus could be used as an effective preventive measure against those severe infestations that are responsible for the spread of pediculosis.

}, keywords = {Argentina, epidemiology, mathematical model}, issn = {0022-2585}, doi = {10.1093/jme/tjy026}, url = {https://academic.oup.com/jme/article/55/4/929/4897907}, author = {Toloza,Ariel Ceferino and Mar{\'\i}a Fabiana Laguna and Isabel Ortega-Insaurralde and Vassena,Claudia V. and Sebasti{\'a}n Risau-Gusman} } @article {47425, title = {Fumigant and repellent properties of essential oils and component compounds against permethrin-resistant Pediculus humanus capitis (Anoplura: Pediculidae) from Argentina}, journal = {Journal of Medical Entomology}, volume = {43}, year = {2006}, month = {2006}, pages = {889 - 895}, abstract = {

The repeated use of permethrin and other insecticides for the control of head lice, Pediculus humanus capitis De Geer (Anoplura: Pediculidae), during past decades has resulted in the development of marked levels of resistance. Thus, new alternative insecticides are needed for the control of head lice. We studied the fumigant and repellent properties of essential oils from 16 native and exotic plants in Argentina, and 21 chemical components against permethrin-resistant head lice from Argentina. With a direct vapor-exposure bioassay, the most effective oil was from the native Myrcianthes cisplatensis Cambess (Myrtaceae) with a time to 50\% knockdown (KT50) of 1.3 min, followed by exotic species, Eucalyptus cinerea F.V. Muell., Eucalyptus viminalis Labill., and Eucalyptus saligna Smith. withKT50 values of 12.0, 14.9, and 17.4 min, respectively. The most effective components were 1,8-cineole and anisole, with KT50 values of 11.1 and 12.7 min, respectively. Regression analysis of KT50 values and vapor pressures and water-partition coef\Þcients for the essential oil components revealed that the most effective fumigants were among the more volatile components. Repellency assays indicated that the essential oil from Mentha pulegium L. and its benzyl alcohol component were the most effective repellents, having repellency indices of 75.5 and 57.8\%, respectively. Thus, some Argentinean plants contain essential oils and components that function as fumigants or as repellents and thereby show potential for development of new control products for head lice.

}, keywords = {Argentina, Essential oils, fumigants, head lice, plants, repellents}, url = {http://www.phthiraptera.info/sites/phthiraptera.info/files/46542.pdf}, author = {Toloza,Ariel Ceferino and Zygadlo,Julio and Mougabure-Cueto,Gast{\'o}n A. and Biurrun,Fernando and Zerba,Eduardo Nicol{\'a}s and Picollo,Mar{\'\i}a In{\'e}s} } @article {47152, title = {Permethrin-Resistant Head Lice (Anoplura: Pediculidae) in Argentina Are Susceptible to Spinosad}, journal = {Journal of Medical Entomology}, volume = {42}, year = {2006}, month = {2006}, pages = {634 - 635}, abstract = {

The insecticidal activity of spinosad was evaluated against susceptible and permethrin-resistant human lice. In a permethrin-susceptible strain of the body louse, Pediculus humanus humanus L. (Anoplura: Pediculidae), the toxicity of spinosad was similar to that established for permethrin, with an LD50 value of 1.2 ng/insect and 2.4 ng/insect, respectively. Topical application of spinosad to populations of permethrin-resistant head louse, Pediculus humanus capitis De Geer (Anoplura: Pediculidae), showed that susceptibility to spinosad was independent of resistance to permethrin. The effectiveness of spinosad against human lice and the low mammalian toxicity reported in the literature suggest that spinosad could be useful for the management of permethrin-resistant human lice.

}, keywords = {Argentina, humanus, spinosad, permethrin, Pediculus, resistance}, url = {https://academic.oup.com/jme/article/43/3/634/880711}, author = {Mougabure-Cueto,Gast{\'o}n A. and Zerba,Eduardo Nicol{\'a}s and Picollo,Mar{\'\i}a In{\'e}s} } @article {47081, title = {Prevalence and levels of Permethrin resistance in Pediculus humanus capitis DeGeer (Anoplura: Pediculidae) from Buenos Aires, Argentina}, journal = {Journal of Medical Entomology}, volume = {40}, year = {2003}, month = {2003}, pages = {447 - 450}, abstract = {

Permethrin has been used extensively for control of Pediculus humanus capitis De Geer(Anoplura: Pediculidae) in Argentina since 1990, resulting in the development of resistance to this and other pyrethroids. This resistance was \Þrst detected in some \Þeld populations in 1997. A survey for resistance in Buenos Aires in 2001 revealed signifcant resistance levels in lice on children at 24 of 26 (92.3\%) schools. When compared with a previously unexposed reference population, resistance ratios (RRs) obtained by exposing the insects to \Þlter papers impregnated with permethrin ranged from 2 to 60 in 10 (39\%) of the schools. RRs in the remaining 14 (61\%) populations were too great to not be measured with the \Þlter paper method (RR 88.7). As an alternative, we used topical applications of 0.1 l of acetone solution of permethrin on the dorsal abdomen of adults and third instars. This topical method, which has not been previously reported for head lice, was capable of quantifying higher levels of resistance. Highly resistant populations had RRs from 162.5 to 655.2. When applied to populations with low and intermediate levels of resistance, results from the \Þlter paper and topical application methods were highly correlated, and RRs from topical application were higher than those from the \Þlter paper method. Results from the combination of the two methods indicated that head lice among Buenos Aries school children are highly resistant to permethrin, and the resistance is widespread.

}, keywords = {Argentina, capitis, Pediculosis, Pediculus, Permethrin}, url = {https://www.researchgate.net/publication/8955671_Prevalence_and_Levels_of_Permethrin_Resistance_in_Pediculus_humanus_capitis_De_Geer_Anoplura_Pediculidae_from_Buenos_Aires_Argentina}, author = {Vassena,Claudia V. and Mougabure-Cueto,Gast{\'o}n A. and Paola Gonz{\'a}lez-Audino and Alzogaray,R. A. and Zerba,Eduardo Nicol{\'a}s and Picollo,Mar{\'\i}a In{\'e}s} } @article {45957, title = {Prevalence of Pediculus humanus capitis infestation in school children at Despenaderos, Cordoba Province}, journal = {Revista de la Facultad de Ciencias Medicas de la Universidad Nac. de Cordoba}, volume = {60}, year = {2003}, note = {LR: 20041117; JID: 8303003; ppublish}, month = {2003}, pages = {43 - 53}, address = {Argentina}, abstract = {

Paper in Spanish. Title: Prevalencia de infestaci\ón por Pediculus humanus capitis en escolares de despe\ñaderos (Provincia de C\órdoba) / Prevalence of pediculus humanus capitis infestation in schoolchildren at Despe\ñaderos, C\órdoba Province

BACKGROUND: Approximately 80\% of Argentine children have pediculosis, making it imperious to detect the defects in the prevention and control actions for this parasitosis. OBJECTIVES: To study the infestation level by P. h. capitis, its temporal variation, and the association between infestation and host characteristics. MATERIALS AND METHODS: A monthly census in children of 6-8 years old from 2 primary schools (state and private) was carried out, recording the parasite stages found, children characteristics (sex, colour and length of hair), and infestation level. Data were analysed by means of contingency tables, difference of proportions, quotient of chances, and rank correlation coefficient. The independence of variables was analysed by c\&$\#$39; test. RESULTS: The prevalence and chances of becoming infested were higher at the state school, where also all infestation levels were recorded, which did not occur at the private institute. The frequency of children infested was significantly lower when they had short hair. The correlation among infestation degree and hair length (short-long) was only significant for boys. Pediculosis cases were recorded at the beginning of the school year in both educative institutions, which demonstrated that infestation was acquired not only at school but also at home. CONCLUSIONS: Pediculosis is a social problems and the whole community must participate in preventive and control actions, for which sanitary education is essential, and the myth that the school is the only place of contagion must be eradicated.

}, keywords = {animals, Argentina, child, English Abstract, humans, Lice Infestations/epidemiology, Pediculus, Prevalence, risk factors, scalp dermatoses, Seasons, Severity of Illness Index, Socioeconomic Factors}, isbn = {0014-6722}, author = {Ramirez,A. and Luduena Almeida,F. F. and Almiron,W. R.} } @article {45886, title = {Prevalence and parasitism intensity by Pediculus humanus capitis in six to eleven-year-old schoolchildren}, journal = {Revista da Sociedade Brasileira de Medicina Tropical}, volume = {37}, year = {2004}, note = {JID: 7507456; ppublish}, month = {2004}, pages = {499 - 501}, address = {Brazil}, abstract = {

The aim of this work was to determine head lice parasitism intensity by Pediculus humanus capitis and its variation, according to both gender and age in 181 school children of a primary school. The intensity was higher among 6 to 8-year-old girls. Pediculosis intensity diminishes significantly between 9 and 11 years of age in both sexes.

}, keywords = {Age Distribution, animals, Argentina, child, English Abstract, humans, Lice Infestations/diagnosis/epidemiology/parasitology, Pediculus, Prevalence, Research Support, Non-U.S. Gov{\textquoteright}t, Rural Population, Sex Distribution, Socioeconomic Factors}, isbn = {0037-8682}, doi = {http://dx.doi.org/10.1590/S0037-86822004000600014 }, url = {http://www.scielo.br/scielo.php?script=sci_arttext\&pid=S0037-86822004000600014\&lng=pt\&tlng=pt}, author = {Catal{\'a},Silvia S. and Carrizo,L. and Cordoba,M. and Khairallah,R. and Moschella,F. and Bocca,J. N. and Calvo,A. N. and Torres,J. and Tutino,R.} } @article {45871, title = {Increased monooxygenase activity associated with resistance to permethrin in Pediculus humanus capitis (Anoplura: Pediculidae) from Argentina}, journal = {Journal of Medical Entomology}, volume = {42}, year = {2005}, month = {2005}, pages = {342 - 345}, abstract = {

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. Fiv

}, keywords = {animals, Argentina, child, humans, Insecticide resistance, Pediculosis, Pediculus, Permethrin, Research Support, Non-U.S. Gov{\textquoteright}t}, url = {https://academic.oup.com/jme/article/42/3/342/849058}, author = {Paola Gonz{\'a}lez-Audino and Barrios,S. and Vassena,Claudia V. and Mougabure-Cueto,Gast{\'o}n A. and Zerba,Eduardo Nicol{\'a}s and Picollo,Mar{\'\i}a In{\'e}s} }