Insecticide resistance associated to environment in Triatoma infestans: what do we know and what remains unknown

Resistance to insecticides is considered as a barrier to chemical control of Triatoma infestans, the main vector of Chagas disease in the Southern Cone of South America. Although initiatives of disease incidence reduction in the area have integrated different strategies, they have been based mainly on vector elimination through pyrethroids insecticides like deltamethrin. The first reports of pyrethroids resistance were found in T. infestans populations from Salvador Mazza (northern Argentina) and Yacuiba (southern Bolivia). Recently, a mosaic pyrethroid resistant focus was described in the center of the Argentine Gran Chaco (General Güemes department, Chaco province), characterized by the presence in the same area of susceptible and very high resistant populations.Para acceder a la videoconferencia completa, hacer clic en "Enlace externo".Sociedad Latinoamericana de Ecología de Vectore

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

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

International recommendations for an effective control of head louse infestations

Head louse infestations continue to be a concern of public health in most countries, including the most developed ones. The present recommendations are intended to inform and stress the role and impact of the different authorities, institutions, industry, and the public in the control of head lice in order to reduce the prevalence of this parasite. We encourage health authorities to pursue more effective methods to correctly identify such infestations, and evaluate existing and new pediculicides, medical devices, louse repellents, and louse- and nit-removal remedies. Pediculicides and medical devices must have verifiable claims in the instructions for use and should be tested periodically to document current levels of resistance by lice to the active ingredients and to the formulated products. Where the prevalence of lice is claimed to be epidemic, children should be periodically evaluated objectively to document the actual level of prevalence. Continuing education for health providers and the general population promises to correct misinformation regarding the biology, prevention, and management of lice. Parents should regularly inspect their children for head lice and treat as necessary. Health authorities are encouraged to eliminate policies and practices that rely upon school exclusion as a means to reduce incidence and prevalence, e.g., the ‘no-nit’ policy which lacks scientific justification, and are counterproductive to the health and welfare of childrenFil: Mumcuoglu, Kosta Y.. The Hebrew University of Jerusalem; IsraelFil: Pollack, Richard J.. Harvard University; Estados UnidosFil: Reed, David L.. University Of Florida. Florida Museum Of History; Estados UnidosFil: Barker, Stephen C.. University of Queensland; AustraliaFil: Gordon, Shirley. Florida Atlantic University; Estados UnidosFil: Toloza, Ariel Ceferino. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Centro de Investigación de Plagas e Insecticidas; ArgentinaFil: Picollo, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Centro de Investigación de Plagas e Insecticidas; ArgentinaFil: Taylan Ozkan, Aysegul. Hitit University; Turquía. Near East University; ChipreFil: Chosidow, Olivier. Hôpital Henri Mondor; FranciaFil: Habedank, Birgit. German Environment Agency; AlemaniaFil: Ibarra, Joanna. Community Hygiene Concern; Reino UnidoFil: Meinking, Terri L.. Global Health Associates of Miami; Estados UnidosFil: Vander Stichele, Robert H.. Heymans Institute of Pharmacology; Bélgic

Potes de fumo, ovitraps e outras ferramentas com baixo impacto ambiental para controlo de barbeiros e mosquitos

The Triatoma infestans bedbug (known in Argentina as “vinchuca”) and four species of mosquitoes (Aedes aegypti, Culex pipiens quinquefasciatus, Anopheles pseudopunctipennis and An. darlingi) are the main insect vectors of disease in Argentina. Since 1977, the Argentine Pest and Insecticide Research Center (CIPEIN) has been doing research on these insects and developing products for their control that have a low impact on human health and the environment. Recognized as a Reference Center by the Pan American Health Organization and the World Health Organization, CIPEIN was a pioneer in the development of insecticide products in Latin America. The aim of this article is to review the status of the health issues involving kissing bugs and mosquitoes in Argentina and to describe the main contributions of CIPEIN to their study and control.La chinche Triatoma infestans (conocida en Argentina como “vinchuca”) y cuatro especies de mosquitos (Aedes aegypti, Culex pipiens quinquefasciatus, Anopheles pseudopunctipennis y An. darlingi) son los principales insectos vectores de enfermedades en el territorio argentino. Desde 1977, el Centro de Investigaciones de Plagas e Insecticidas de Argentina (CIPEIN) investiga a estos insectos y desarrolla productos para controlarlos con un bajo impacto para la salud humana y el ambiente. Reconocido como Centro de Referencia por la Organización Panamericana de la Salud y la Organización Mundial de la Salud, el CIPEIN fue pionero en el desarrollo de productos insecticidas en América Latina. El objetivo de este artículo es reseñar la situación de la problemática sanitaria que involucra a vinchucas y mosquitos en Argentina, y describir los principales aportes del CIPEIN en su estudio y control.O hematófago Triatoma infestans (conhecido na Argentina como “vinchuca”) e quatro espécies de mosquitos (Aedes aegypti, Culex pipiens quinquefasciatus, Anopheles pseudopunctipennis e An. darlingi) são os principais insetos vetores de doenças no território argentino. Desde 1977, o Centro Argentino de Investigação de Pragas e Inseticidas (CIPEIN) investiga esses insetos e desenvolve produtos para controlá-los com baixo impacto na saúde humana e no meio ambiente. Reconhecido como Centro de Referência pela Organização Pan-Americana da Saúde e pela Organização Mundial da Saúde, o CIPEIN foi pioneiro no desenvolvimento de produtos inseticidas na América Latina. O objetivo deste artigo é fazer uma revisão da situação do problema de saúde envolvendo barbeiros e mosquitos na Argentina e descrever as principais contribuições da CIPEIN no seu estudo e controlo

Aerosolized BC-819 Inhibits Primary but Not Secondary Lung Cancer Growth

Despite numerous efforts, drug based treatments for patients suffering from lung cancer remains poor. As a promising alternative, we investigated the therapeutic potential of BC-819 for the treatment of lung cancer in mouse tumor models. BC-819 is a novel plasmid DNA which encodes for the A-fragment of Diphtheria toxin and has previously been shown to successfully inhibit tumor growth in human clinical study of bladder carcinoma. In a first set of experiments, we examined in vitro efficacy of BC-819 in human lung cancer cell-lines NCI-H460, NCI-H358 and A549, which revealed >90% reduction of cell growth. In vivo efficacy was examined in an orthotopic mouse xenograft lung cancer model and in a lung metastasis model using luminescent A549-C8-luc adenocarcinoma cells. These cells resulted in peri- and intra-bronchiolar tumors upon intrabronchial application and parenchymal tumors upon intravenous injection, respectively. Mice suffering from these lung tumors were treated with BC-819, complexed to branched polyethylenimine (PEI) and aerosolized to the mice once per week for a period of 10 weeks. Using this regimen, growth of intrabronchially induced lung tumors was significantly inhibited (p = 0.01), whereas no effect could be observed in mice suffering from lung metastasis. In summary, we suggest that aerosolized PEI/BC-819 is capable of reducing growth only in tumors arising from the luminal part of the airways and are therefore directly accessible for inhaled BC-819

Nuclear genetic diversity of head lice sheds light on human dispersal around the world.

The human louse, Pediculus humanus, is an obligate blood-sucking ectoparasite that has coevolved with humans for millennia. Given the intimate relationship between this parasite and the human host, the study of human lice has the potential to shed light on aspects of human evolution that are difficult to interpret using other biological evidence. In this study, we analyzed the genetic variation in 274 human lice from 25 geographic sites around the world by using nuclear microsatellite loci and female-inherited mitochondrial DNA sequences. Nuclear genetic diversity analysis revealed the presence of two distinct genetic clusters I and II, which are subdivided into subclusters: Ia-Ib and IIa-IIb, respectively. Among these samples, we observed the presence of the two most common louse mitochondrial haplogroups: A and B that were found in both nuclear Clusters I and II. Evidence of nuclear admixture was uncommon (12%) and was predominate in the New World potentially mirroring the history of colonization in the Americas. These findings were supported by novel DIYABC simulations that were built using both host and parasite data to define parameters and models suggesting that admixture between cI and cII was very recent. This pattern could also be the result of a reproductive barrier between these two nuclear genetic clusters. In addition to providing new evolutionary knowledge about this human parasite, our study could guide the development of new analyses in other host-parasite systems