Presencia y distribución espacial de Simulium sp. (Díptera: Simuliidae) en dos provincias de Angola / Presence and spatial distribution of Simuliumsp.(Diptera: Simuliidae) in two provinces of Angola

En el oeste de África los miembros del complejo Simulium damnosum son los vectores de la oncocercosis. El objetivo es obtener datos sobre la presencia y distribución de simúlidos en dos provincias de Angola. El trabajo se realizó en las provincias de Huambo y Bié donde se muestrearon 24 cuerpos de agua entre julio y agosto, 2015. Todos los sitios se localizaron por encima de una altitud de 1 000 m y solo tres resultaron negativos a la presencia de simúlidos. Estos resultados constituyen los primeros que se obtienen sobre la presencia y distribución espacial de Simulium sp. en Angola de gran importancia, pues la superposición de los mapas de distribución de la infección humana y los vectores permiten localizar áreas con peligro de transmisión(AU)

In West Africa Simuliumdamnosum complex members are the main vectors of onchocerciasis. The objective of this paper was to collect data on the presence and spatial distribution of black flies in two provinces of Angola. The research work was conducted in Huambo and Bié provinces where 24 water bodies were sampled between July and August 2015. All the studied sites were located above 1 000 m of altitude and only three of them were found to be negative for the presence of black flies. These were the first results obtained on the presence and spatial distribution of Simulium sp. in Angola and are of great importance because overlapping the distribution maps of human infection and of vectors allows finding the areas at risk of transmission(AU)

Nodding syndrome since 2012: recent progress, challenges and recommendations for future research.

We aim to review the current epidemiology of nodding syndrome (NS) and discuss relevant gaps in research. NS and convulsive epilepsy of unknown aetiology are clustered within the same villages and families in onchocerciasis-endemic areas. They are therefore potentially different clinical expressions of the same disease. It has been difficult to perform full autopsies on NS patients who die in remote villages. Adequate fixation of tissue immediately after death is critical for the examination of brain tissue. Therefore, post-mortem transsphenoidal brain biopsies, performed immediately after death by trained nurses, will provide the best option for obtaining tissue for analysis. We suspect that certain blackflies in onchocerciasis-endemic areas may transmit a novel pathogen that could cause NS and epilepsy. This is supported by a recent drop in the number of new NS cases coinciding with vector control activities aimed at reducing blackfly populations in northern Uganda. We propose that metagenomic studies of human samples, blackflies and microfilariae are conducted to screen for pathogens, and that a clinical trial is planned to evaluate the impact of larviciding against NS and epilepsy epidemics.

Major histocompatibility complex and other allergy-related candidate genes associated with insect bite hypersensitivity in Icelandic horses.

Insect bite hypersensitivity (IBH) is an allergic dermatitis of horses caused by bites of insects. IBH is a multifactorial disease with contribution of genetic and environmental factors. Candidate gene association analysis of IBH was performed in a group of 89 Icelandic horses all born in Iceland and imported to Europe. Horses were classified in IBH-affected and non-affected based on clinical signs and history of recurrent dermatitis, and on the results of an in vitro sulfidoleukotriene (sLT)-release assay with Culicoides nubeculosus and Simulium vittatum extract. Different genetic markers were tested for association with IBH by the Fisher's exact test. The effect of the major histocompatibility complex (MHC) gene region was studied by genotyping five microsatellites spanning the MHC region (COR112, COR113, COR114, UM011 and UMN-JH34-2), and exon 2 polymorphisms of the class II Eqca-DRA gene. Associations with Eqca-DRA and COR113 were identified (p < 0.05). In addition, a panel of 20 single nucleotide polymorphisms (SNPs) in 17 candidate allergy-related genes was tested. During the initial screen, no marker from the panel was significantly (p < 0.05) associated with IBH. Five SNPs associated with IBH at p < 0.10 were therefore used for analysis of combined genotypes. Out of them, SNPs located in the genes coding for the CD14 receptor (CD14), interleukin 23 receptor (IL23R), thymic stromal lymphopoietin (TSLP) and transforming growth factor beta 3 (TGFB3) molecules were associated with IBH as parts of complex genotypes. These results are supported by similar associations and by expression data from different horse populations and from human studies.

Black fly salivary gland extract inhibits proliferation and induces apoptosis in murine splenocytes.

Black flies are known to be vectors of pathogens including Onchocerca volvulus, which causes human onchocerciasis, and Vesicular Stomatitis Virus. Their salivary secretion has been shown to contain a complex cocktail of anti-haemostatic factors and immunomodulatory activities, which may contribute to efficient transmission of the pathogens. Black fly salivary gland extract (SGE) inhibits mitogen-stimulated mouse splenocyte proliferation, including proliferation of both CD4(+) and CD8(+) T cells. The factor responsible for the inhibition was determined to be a protein (or protein complex) of a size larger than 50 kDa. Moreover, exposure to SGE results in activation of caspase 3 and characteristic morphological changes in CD4(+) and CD8(+) T cells, suggesting that induction of apoptosis could, at least in part, be responsible for this inhibition.

[Evaluation of cocoa oil for individual protection against Simulium damnosum s.i]. / Evaluation de l'efficacité de l'huile de coco contre les piqûres de Simulium damnosum s.i.

Thanks to larviciding and distribution of ivermectine, transmission of onchocerciasis was virtually halted in all countries covered by the WHO Onchocerciasis Control Program (OCP). However as a result of this success vector control has been stopped in most areas covered by the program and a recrudescence of files is an increasing problem. In some rural communities fly biting hinders normal agricultural activity. Since local farmers cannot afford ground larviciding, many rely on topical repellents. For this reason, development of an inexpensive method of individual protection is a major priority. The purpose of this study carried out in the savannah area of the Côte d'Ivoire was to assess the repellent properties of cocoa oil, which is frequently used in some rural areas of the Côte d'Ivoire to prevent fly biting. Results showed that cocoa oil provides excellent protection against Simulium damnosum s.l.

[Observation in France of Simulium erythrocephalum De Geer, 1776 as an agent of human simuliidosis]. / Observation en France de Simulium erythrocephalum De Geer, 1776 comme agent de simuliidose humaine.

Second observation of this black-fly in human simuliidosis. The country is the department of Vaucluse.

Aspectos ecológicos de Simulium goeldii (Diptera: Simuliidae): relação entre substrato e densidade de larvas / Ecological aspects of Simulium goeldii (Diptera: Simuliidae: relation between substrate and larval density

The distribution of larvae of Simulium goeldii was studies in four streams in upland tropical forest near Manaus, Amazonas, Brazil. In each month 32 points were sampled, each with an area of 30 x 50 cm. The areas of all substrates available were measured at each point. The larvae of S. goeldii were collected and later counted for all substrate types where larvae of this species were found. The available substrates were classified into eight types: dry leaves, green leaves, branches, fruits, detritus, rocks and sand; anly the first four types had larvae present. The Kruskal-Wallis test and analysis of variance indicated that the larvae occupy these substrates differently; the Newman-Keuls identified the following differences in intensity of occupation of the susbstrates: branchs differ from roots, dry leaves and green leaves, and green leaves differ from roots and dry leaves. The highest density of larvae was observed on green leaves. However, because the most abundant substrates in the study area were roots and dry leaves, I suggest that the latter two substrates are the most important ones for the esteblishment of this population of S. goeldii.