Larvicidal activity of plants from Myrtaceae against Aedes aegypti L. and Simulium pertinax Kollar (Diptera)

Abstract INTRODUCTION: Despite their widespread usage, synthetic insecticides and larvicides are harmful for controlling disease-causing mosquitoes owing to the development of resistance. The leaves of Eugenia astringens, Myrrhinium atropurpureum, and Neomitranthes obscura were collected from Marambaia and Grumari restingas. The safety and larvicidal efficacy of their extracts were tested against Aedes (Stegomyia) aegypti L. and Simulium (Chirostilbia) pertinax Kollar. METHODS: The dry leaves were subjected to static maceration extraction using 90% methanol. A. aegypti and S. pertinax larvae were exposed to 7.5, 12.5, and 25.0 µL/mL of the extracts (n= 30). The larvicidal activity after 24 h and 48 h, and the mortality, were determined. The median lethal concentration (CL50) was estimated by a Finney's probit model. RESULTS: M. atropurpureum and E. astringens extracts exhibited the strongest larvicidal effects against A. aegypti. M. atropurpureum extracts (25 µL/mL) caused mortalities of over 50% and 100% after 24 h and 48 h, respectively (CL50 = 11.10 and 9.68 ppm, respectively). E. astringens extracts (25 µL/mL) caused mortalities of 50% and 63.33% after 24 h and 48 h, respectively. High concentrations of N. obscura extracts induced a maximum mortality of 46.66% in A. aegypti larvae after 48 h (CL50= 25 ppm). The larvae of S. pertinax showed 100% mortality following exposure to all the plant extracts at all the tested concentrations after 24 h. CONCLUSIONS: The extracts of M. atropurpuerum exhibited the strongest larvicidal activity against A. aegypti. The larvae of S. pertinax were sensitive to all the extracts at all the tested concentrations.

Larvicidal activity of plants from Myrtaceae against Aedes aegypti L. and Simulium pertinax Kollar (Diptera).

INTRODUCTION: Despite their widespread usage, synthetic insecticides and larvicides are harmful for controlling disease-causing mosquitoes owing to the development of resistance. The leaves of Eugenia astringens, Myrrhinium atropurpureum, and Neomitranthes obscura were collected from Marambaia and Grumari restingas. The safety and larvicidal efficacy of their extracts were tested against Aedes (Stegomyia) aegypti L. and Simulium (Chirostilbia) pertinax Kollar. METHODS: The dry leaves were subjected to static maceration extraction using 90% methanol. A. aegypti and S. pertinax larvae were exposed to 7.5, 12.5, and 25.0 µL/mL of the extracts (n= 30). The larvicidal activity after 24 h and 48 h, and the mortality, were determined. The median lethal concentration (CL50) was estimated by a Finney's probit model. RESULTS: M. atropurpureum and E. astringens extracts exhibited the strongest larvicidal effects against A. aegypti. M. atropurpureum extracts (25 µL/mL) caused mortalities of over 50% and 100% after 24 h and 48 h, respectively (CL50 = 11.10 and 9.68 ppm, respectively). E. astringens extracts (25 µL/mL) caused mortalities of 50% and 63.33% after 24 h and 48 h, respectively. High concentrations of N. obscura extracts induced a maximum mortality of 46.66% in A. aegypti larvae after 48 h (CL50= 25 ppm). The larvae of S. pertinax showed 100% mortality following exposure to all the plant extracts at all the tested concentrations after 24 h. CONCLUSIONS: The extracts of M. atropurpuerum exhibited the strongest larvicidal activity against A. aegypti. The larvae of S. pertinax were sensitive to all the extracts at all the tested concentrations.

Elimination of Simulium neavei-Transmitted Onchocerciasis in Wambabya-Rwamarongo Focus of Western Uganda.

Wambabya-Rwamarongo onchocerciasis focus is one of the eight foci Uganda verified using the WHO verification guidelines. The approach for elimination was twice yearly treatment with ivermectin for every round, treating at least 90% of all the eligible population. This was in combination with vector elimination using Abate® (BASF SE, Limburgerhof, Germany) since elimination nationwide policy was launched. From 2008 to 2013, the program distributed ivermectin with a mean treatment coverage of the ultimate treatment goal (UTG) or eligible population of 91.2%, with a range of 85-96%. In 2009, vector elimination based on ground larviciding had a dramatic impact on the Simulium vectors, as the last fly was observed in October 2009. No more Simulium vectors were observed during a period of at least 7 years, including the 3-year posttreatment surveillance (PTS) until the focus was reclassified as eliminated in August 2017. During the PTS period, none of the 10,578 trapped crabs were found infested with the aquatic stages of the vector. The last infested crab was observed in March 2010, and for at least 7 years, no infested crabs were observed. Serological surveys showed that of 2,978 young children examined in 2013, only one was OV16 positive (0.0%; 95% CI: 0-0.21). In 2017, after the PTS period, all 3,079 young children examined were negative for OV16 (95% CI: 0-0.16). Therefore, entomological and serological results provided evidence that resulted in the reclassification of Wambabya-Rwamarongo focus from "transmission interrupted" to "transmission eliminated" with no possibility of recrudescence.

Digestibility of black soldier fly larvae (Hermetia illucens) fed to leopard geckos (Eublepharis macularius).

Black soldier fly (BSF) larvae have been marketed as an excellent choice for providing calcium to reptiles without the need of dusting or gut loading. However, previous studies have indicated that they have limited calcium digestibility and are deficient in fat soluble vitamins (A, D3, and E). In this feeding and digestibility trial, 24 adult male leopard geckos were fed one of three diets for 4 months: 1) whole, vitamin A gut loaded larvae; 2) needle pierced, vitamin A gut loaded larvae; or 3) whole, non-gut loaded larvae. Fecal output from the geckos was collected daily and apparent digestibility was calculated for dry matter, protein, fat, and minerals. There were no differences in digestibility coefficients among groups. Most nutrients were well digested by the leopard geckos when compared to previous studies, with the exception of calcium (digestibility co-efficient 43%), as the calcium-rich exoskeleton usually remained intact after passage through the GI tract. Biochemistry profiles revealed possible deficits occurring over time for calcium, sodium, and total protein. In regards to vitamin A digestibility, plasma and liver vitamin A concentrations were significantly higher in the supplemented groups (plasma- gut loaded groups: 33.38 ± 7.11 ng/ml, control group: 25.8 ± 6.72 ng/ml, t = 1.906, p = 0.04; liver- gut loaded groups: 28.67 ± 18.90 µg/g, control group: 14.13 ± 7.41 µg/g, t = 1.951, p = 0.03). While leopard geckos are able to digest most of the nutrients provided by BSF larvae, including those that have been gut loaded, more research needs to be performed to assess whether or not they provide adequate calcium in their non-supplemented form.

Dose-Dependent Retention of Omega-3 Fatty Acids by Black Soldier Fly Larvae (Diptera: Stratiomyidae).

Black soldier fly larvae, Hermetia illucens (L.), are used to convert organic waste streams into insect-based animal feeds. We tested their ability to retain alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) from feeding substrates, which has important implications for their use in aquaculture. When supplementing a chicken feed diet with increasing concentrations of salmon oil (0-42%) over an increasing number of days (0-8), the concentrations of the three omega-3 acids in larvae increased significantly. Larval survival and biomass accumulation were not affected. Supplementing a chicken feed diet with increasing concentrations (0-14%) of Tetraselmis chui Butcher (Chlorodendrales: Chlorodendraceae) microalgae paste also significantly increased ALA and EPA contents of the harvested larvae. However, microalgae also decreased survival, harvested biomass, and individual growth of larvae feeding on the diet with the highest supplement concentration (14%). DHA was not detected in any microalgae diet or subsequent larval tissue samples. All three omega-3 polyunsaturated fatty acids tested in this study were accumulated in dose-dependent manner, with quadratic, and occasionally linear, equations providing the best description of the observed relationships. There were significant negative correlations between several fatty acids, indicating that they may replace one another in living larvae. Our findings confirm that black soldier fly larvae can retain ingested fatty acids and change fatty acid profiles in their tissues accordingly. However, optimizing nutrient content of harvestable larvae is likely to be more complicated than simply enriching their diets with omega-3 fatty acids.

Replacement of soybean oil by Hermetia illucens fat in turkey nutrition: effect on performance, digestibility, microbial community, immune and physiological status and final product quality.

1. The aim of the present study was to investigate the effect of partial (50%) or total replacement of soybean oil (SO) by black soldier fly larvae (BSFL) fat on the growth performance, coefficients of apparent nutrient digestibility, selected internal organ weights and length, pancreatic enzyme activity and gastrointestinal tract (GIT) microecology modulation, as well as microbiota activity, physiological and immunological responses in young turkey poults. 2. A total of 216, seven day old female turkeys (B.U.T 6) were randomly distributed to three dietary treatments using six replicate pens per group with 12 birds per pen. The following design of the trial was applied: SO 100% soybean oil; BSFL50 a 50/50 combination of SO and BSFL fat; or 100% BSFL fat (total replacement of SO). 3. The use of BSFL fat did not affect the growth performance, nutrient digestibility, GIT morphology, or quality of the breast and thigh muscles. However, reduced trypsin activity was noticed in the BSFL100 group, but this had no effect on digestibility. Total replacement of SO reduced proliferation of potentially pathogenic bacteria, i.e., Enterobacteriaceae spp., as well as decreasing levels of IL-6, while partial substitution lowered the TNF-α concentration. 4. The replacement of commonly used SO by BSFL fat can be successfully applied in young turkey poult nutrition. BSFL fat may be considered an antimicrobial agent and support immune responses.

An inclusive approach for organic waste treatment and valorisation using Black Soldier Fly larvae: A review.

Solid waste management and its stabilization are a sophisticated task and the most challenging one as it requires improved collection and treatment strategies. From the past decades, there is a huge emphasis on valorisation of waste along with its management i.e. an integrated and income generating sustainable approach for solid waste management. Use of Black Soldier Fly (Hermetia illucens) in organic waste composting is a novel and an environment friendly approach which holds enormous potential and therefore, is strongly captivating people's attention worldwide. The Black Soldier Fly (BSF) larvae composting is a self-sustained cost-effective method promoting high resource recovery and generating value added products thereby developing new economical niches for industrial sector and entrepreneurs in developing countries. Here, we reviewed the importance of BSF larvae in organic waste treatment and delineated the life cycle patterns, feeding habits and environmental conditions affecting the survival of the species. This review paper has also congregated the efficiency of BSF larvae to compost different types of organic wastes or biomasses and a portion of various possible end applications of these avid eaters. Through this literature review the authors have also made an attempt to evaluate the present constraints, research gaps and future directions associated with this technology. BSF larvae composting is a comprehensive approach indeed providing the waste an aforementioned value wherein technological innovations can boost up the efficiency of system. Thus, the present study is an aggregate of applications of BSF larvae for societal benefit in a holistic way.

The nutritive value of black soldier fly larvae reared on common organic waste streams in Kenya.

In Africa, livestock production currently accounts for about 30% of the gross value of agricultural production. However, production is struggling to keep up with the demands of expanding human populations, the rise in urbanization and the associated shifts in diet habits. High costs of feed prevent the livestock sector from thriving and to meet the rising demand. Insects have been identified as potential alternatives to the conventionally used protein sources in livestock feed due to their rich nutrients content and the fact that they can be reared on organic side streams. Substrates derived from organic by-products are suitable for industrial large-scale production of insect meal. Thus, a holistic comparison of the nutritive value of Black Soldier Fly larvae (BSFL) reared on three different organic substrates, i.e. chicken manure (CM), brewers' spent grain (SG) and kitchen waste (KW), was conducted. BSFL samples reared on every substrate were collected for chemical analysis after the feeding process. Five-hundred (500) neonatal BSFL were placed in 23 × 15 cm metallic trays on the respective substrates for a period of 3-4 weeks at 28 ± 2 °C and 65 ± 5% relative humidity. The larvae were harvested when the prepupal stage was reached using a 5 mm mesh size sieve. A sample of 200 grams prepupae was taken from each replicate and pooled for every substrate and then frozen at -20 °C for chemical analysis. Samples of BSFL and substrates were analyzed for dry matter (DM), crude protein (CP), ether extracts (EE), ash, acid detergent fibre (ADF), neutral detergent fibre (NDF), amino acids (AA), fatty acids (FA), vitamins, flavonoids, minerals and aflatoxins. The data were then subjected to analysis of variance (ANOVA) using general linear model procedure. BSFL differed in terms of nutrient composition depending on the organic substrates they were reared on. CP, EE, minerals, amino acids, ADF and NDF but not vitamins were affected by the different rearing substrates. BSFL fed on different substrates exhibited different accumulation patterns of minerals, with CM resulting in the largest turnover of minerals. Low concentrations of heavy metals (cadmium and lead) were detected in the BSFL, but no traces of aflatoxins were found. In conclusion, it is possible to take advantage of the readily available organic waste streams in Kenya to produce nutrient-rich BSFL-derived feed.

Diversity and ecology of black flies in tea plantation area of Puncak Bogor, Indonesia.

Black flies fauna in Indonesia has been studied extensively, however their ecology is still remaining unexplored. The study was carried out by collecting the larvae and pupae black flies in tea plantation area, Puncak Bogor. The collection sites were the streams located in 3 differents type of altitude, i.e. (1) the natural forest area (1200 m above the sea level) (P1); (2) the tea plantation area (900-1200 m asl) (P2); and (3) the housing area of the official tea plantation (900 m asl) (P3). The collection of black flies were done beweekly from July 2012 to April 2013. The result showed that 12 species of black flies were recorded which belong to one genus, Simulium s.l. and three subgenera (Nevermannia, Gomphostilbia and Simulium s.str). In P1, the area with high elevation (natural forest), it was found the most number of black flies species (11 species). In the streams around and in the tea plantation area (P2), it was found 7 species, and in P3, the official housing area, it was recorded 8 species. The analysis satistically showed that P1 was dominated by larvae and pupae of S. (S.) argyrocinctum, P2 by larvae and pupae of S. (N.) feuerborni, and P3 by S. (S.) argyrocinctum and S. (N.) feuerborni. The distribution of these species was different according to the elevation of the areas.

Black soldier fly larva fat inclusion in finisher broiler chicken diet as an alternative fat source.

The objective of the present study was to evaluate the effects of partial or total replacement of finisher diet soybean oil with black soldier fly (Hermethia illucens L.; HI) larva fat on the growth performance, carcass traits, blood parameters, intestinal morphology and histological features of broiler chickens. At 21 days of age, a total of 120 male broiler chickens (Ross 308) were randomly allocated to three experimental groups (five replicates and eight birds/pen). To a basal control diet (C; 68.7 g/kg as fed of soybean oil), either 50% or 100% of the soybean oil was replaced with HI larva fat (HI50 and HI100 group, respectively). Growth performance was evaluated throughout the trial. At day 48, 15 birds (three birds/pen) per group were slaughtered at a commercial abattoir. Carcass yield and proportions of carcass elements were recorded. Blood samples were taken from each slaughtered chicken for haematochemical index determination. Morphometric analyses were performed on the duodenum, jejunum and ileum. Samples of liver, spleen, thymus, bursa of fabricius, kidney and heart were submitted to histological investigations. Growth performance, carcass traits, haematochemical parameters and gut morphometric indexes were not influenced by the dietary inclusion of HI larva fat. Histopathological alterations developed in the spleen, thymus, bursa of fabricius and liver and were identified in all of the experimental groups, but HI larva fat inclusion did not significantly affect (P>0.05) the severity of the histopathological findings. The present study suggests that 50% or 100% replacement of soybean oil with HI larva fat in broiler chickens diets has no adverse effects on growth performance or blood parameters and had no beneficial effect on gut health.

Black soldier fly as dietary protein source for broiler quails: meat proximate composition, fatty acid and amino acid profile, oxidative status and sensory traits.

In the perspective of improving the sustainability of meat production, insects have been rapidly emerging as innovative feed ingredient for some livestock species, including poultry. However, at present, there is still limited knowledge regarding the quality and sensory traits of the derived meat. Therefore, the present study tested the effect of a partial substitution of soya bean meal and oil with defatted black soldier fly (Hermetia illucens) larvae meal (H) in the diet for growing broiler quails (Coturnix coturnix japonica) on meat proximate composition, cholesterol, amino acid and mineral contents, fatty acid profile, oxidative status and sensory characteristics. To this purpose, three dietary treatments were designed: a control diet (C) and two diets (H1 and H2) corresponding to 10% and 15% H inclusion levels, respectively, were fed to growing quails from 10 to 28 days of age. At 28 days of age, quails were slaughtered and breast meat was used for meat quality evaluations. Meat proximate composition, cholesterol content and oxidative status remained unaffected by H supplementation as well as its sensory characteristics and off-flavours perception. Differently, with increasing the dietary H inclusion, the total saturated fatty acid and total monounsaturated fatty acid proportions raised to the detriment of the polyunsaturated fatty acid fraction thus lowering the healthiness of the breast meat. The H2 diet increased the contents of aspartic acid, glutamic acid, alanine, serine, tyrosine and threonine thus further enhancing the biological value of the meat protein. As a direct result of the dietary content of Ca and P, the meat of quails fed with the highest H level, displayed the highest Ca and the lowest P values. Therefore, meat quality evaluations confirmed H to be a promising insect protein source for quails. The only potential drawback from feeding H to broiler quails regarded the fatty acid profile of the meat, therefore requiring further research efforts to understand to what extent the fatty acid profile of H can be improved.

Transmission of Onchocerca volvulus continues in Nyagak-Bondo focus of northwestern Uganda after 18 years of a single dose of annual treatment with ivermectin.

The objective of the study was to determine whether annual ivermectin treatment in the Nyagak-Bondo onchocerciasis focus could safely be withdrawn. Baseline skin snip microfilariae (mf) and nodule prevalence data from six communities were compared with data collected in the 2011 follow-up in seven communities. Follow-up mf data in 607 adults and 145 children were compared with baseline (300 adults and 58 children). Flies collected in 2011 were dissected, and poolscreen analysis was applied to ascertain transmission. Nodule prevalence in adults dropped from 81.7% to 11.0% (P < 0.0001), and mf prevalence dropped from 97.0% to 23.2% (P < 0.0001). In children, mf prevalence decreased from 79.3% to 14.1% (P < 0.0001). Parous and infection rates of 401 flies that were dissected were 52.9% and 1.5%, respectively, whereas the infective rate on flies examination by polymerase chain reaction (PCR) was 1.92% and annual transmission potential was 26.9. Stopping ivermectin treatment may result in onchocerciasis recrudescence.

Efficacy of DEET and non-DEET-based insect repellents against bites of Simulium damnosum vectors of onchocerciasis.

Coping strategies including smoke screens are used against nuisance bites of Simulium damnosum Theobald (Diptera:Simuliidae) in onchocerciasis endemic communities. To find more effective alternatives, the efficacy of commercially available N,N-diethyl-3-methylbenzamide (DEET) products with active concentrations of 9.5, 13, 25, 50 and 98.1-100% and 'NO MAS,' (active component: para-menthane-3,8-diol and lemon grass oil) were tested at Bui-Agblekame, Ghana. A Latin square study design was implemented using eight groups of two vector collectors each, who used repellents (treatment), mineral oil or nothing each day until the end of the study. Flies were caught and their numbers each hour recorded using the standard methods for onchocerciasis transmission studies. T-tests were used to compare the mean duration of protection and a one-way analysis of variance controlling for catchers and repellents was performed. Tukey's test was used to compare protection by repellents and mineral oil. The highest percentage protection was 80.8% by NO MAS and the least 42.5% by the 13% DEET product. The period of absolute protection was 5 h by NO MAS and 1 h by 50% DEET product. No significant increase in protection was offered beyond 25% active DEET products and no significance was observed in terms of catcher × repellent effect (F = 1.731, d.f. = 48, P = 0.209).

Repellent activity of some essential oils against Simulium species in India.

Use of repellents seems to be most reliable method of personal protection against annoyance and infections associated with haematophagous insects. We have investigated the biting activity of Simulium and tested the repellency of five essential oils extracted from Homalomena aromatica Schott (Alismatales: Araceae), Pogostemon heyneanus Bentham (Lamiales: Lamiaceae), Citrus aurantifolia Swingle (Sapindales: Rutaceae), Vitex negundo L. (Lamiales: Lamiaceae), and Ageratum conzoides L. (Asterales: Asteraceae) on the human volunteers against Simulium (blackflies) in three locations of Arunachal Pradesh, India. Blackflies preferred biting legs (> 79%) as compared to hand and face with profound biting activity during 1000-1100 h (> 23%) and 1500 - 1600 h (> 28%). The essential oil extracted from Homalomena aromatica, Vitex negundo and Ageratum conizoides provided > 2 h protection at 5% concentration and > 5 h protection at 10% concentration in all the three testing locations. The repellency of Homalomena aromatica, Vitex negundo and Ageratum conizoides essential oils after 6 h application was > 50% at 5% concentration and > 90% at 10% concentration. The study provides evidence for the potential of these essential oils in developing new repellents against blackflies.

Field evaluation of repellency of a polyherbal essential oil against blackflies and its dermal toxicity using rat model.

In the present study we have evaluated the repellent activity of mixture of Curcuma longa, Zanthoxylum limonella and Pogostemon heyneanus essential oils in 1:1:2 ratio at 5%, 10% and 20% concentration against blackflies in northeastern India. Initially the essential oil mixture tested here has been found effective against Aedes albopictus mosquitoes. The average protection recorded in 20% concentration (170.56 ± 4.0; 95% CI = 162.09-179.02) was higher as compared to other two concentrations (F = 90.2; p<0.0001; df = 53). Percentage repellency and repellency index was found to be higher in 20% concentration (p ≤ 0.017). No appreciable clinical and behavioral signs were observed in the acute dermal toxicity using rat model. No changes were observed in biochemical profiles of treatment group animals. Similarly, no prominent lesions were observed in vital organs of treatment in both the sexes. The study concludes that tested repellent is safe for use and has multi-insects repellent property.

Comparative repellent activities of some plant extracts against Simulium damnosum complex.

The root and leaf extracts of four plants, Occimum gratissimum, Azadirachta indica, Pterocarpus santalinoides, and Pistia hyptis, were studied for repellent activities against the adults of Simulium damnosum sensu lato. The leaves and roots were extracted with 95% ethanol and the stocks were diluted with paraffin. The repellent activities of the extracts were investigated using human baits along the banks of River Oyan and River Ogun in southwestern Nigeria. The results showed that the root extract of O. grattissium and leaf extract of P. hyptis had highest repellent potentials with 78% and 78.1% protection against S. damnosum sensu lato, respectively, whereas the root and leaf of P. santalinoides recorded the least. Although there were significant differences in the percentage of protection of the extracts of the plants (p < 0.05), the variations in the percentage of protection of the leaf and root extracts were not statistically significant (p > 0.05). The study concludes that there exist some repellent efficacies in the extracts of the plants, most importantly O. grattissimum and P. hyptis. The plant extracts can further be developed in the prevention of man-vector contact in onchocerciasis endemic communities.

Testing the use of a citronella-based repellent as an effective method to reduce the prevalence and abundance of biting flies in avian nests.

Here, we validate the use of a citronella (natural oil) based repellent to reduce the abundance of flying blood-sucking insects in avian nests. These insects are important parasites of birds affecting them as blood feeders and as vectors of a diversity of pathogens. When nestling were 10 days old, we assigned wild great tit Parus major nests to one of two treatments, control and fumigated nests. The abundance of biting midges and blackflies captured during 3 days following the treatment application were lower in fumigated nests with respect to control ones. By contrast, the abundance of blowfly pupae measured when nestlings left their nests was not affected by the treatment. Although many experimental studies modify the abundance of nest-dweller ectoparasites, to our knowledge, this is the first one describing an easy, safe, and effective method, reducing the total abundance of both biting midges and blackflies in wild avian nests. Our results could be used in future conservation projects and experimental studies on host-parasite evolution affecting the abundance of flying blood-feeder insects under natural conditions.

Repellency of hydrogenated catmint oil formulations to black flies and mosquitoes in the field.

The essential oil of catmint, Nepeta cataria L., was hydrogenated to yield an oil enriched in dihydronepetalactone (DHN) diastereomers, termed. This material was used for the preparation of liquid alcohol-based and lotion formulations. The efficacy of these formulations as repellents was tested after application to human test subjects at two locations in the United States: Maine and Florida. In Maine, data on repellency of the hydrogenated catmint oil formulations toward black flies (Simulium decorum Walker) and mosquitoes (primarily Aedes intrudens Dyar) were obtained. In these tests, protection from black flies was conferred for 6 h or more with all formulations, and both liquid and lotion formulations at 15 wt% active ingredient gave complete protection for 7.5 h. All formulations conferred protection from mosquitoes for >4 h, with the best (15 wt% lotion) giving >8 h of complete protection. In Florida, data on repellency toward a mixed population of mosquitoes indicated that all formulations conferred protection for >4 h, with the 15 wt% lotion giving >6 h complete protection from bites.

The Onchocerciasis Elimination Program for the Americas (OEPA).

Human onchocerciasis (river blindness) occurs in 13 foci distributed among six countries in Latin America (Brazil, Colombia, Ecuador, Guatemala, Mexico and Venezuela), where about 500,000 people are considered at risk. An effort to eliminate the disease from the region was launched in response to a specific resolution adopted by the PanAmerican Health Organization (PAHO) in 1991: to eliminate onchocerciasis from the region, as a public-health problem, by 2007. The effort took advantage of the donation of the drug Mectizan (ivermectin) by Merck & Co., Inc. In 1992, the Onchocerciasis Elimination Program for the Americas (OEPA) was launched, with its headquarters in Guatemala, to act as a technical and co-ordinating body of a multinational, multi-agency coalition that includes the endemic countries, PAHO, The Carter Center, Lions Clubs, the United States Centers for Disease Control and Prevention, The Bill and Melinda Gates Foundation, Merck & Co., Inc., and other partners. This public-private partnership facilitated the establishment of programmes for the semi-annual mass administration of Mectizan in the six countries with onchocerciasis. The aims were to (1) provide sustained treatments, with coverage reaching at least 85% of those eligible to receive the drug (in the 1845 endemic communities that are distributed within the 13 regional foci); (2) eliminate new morbidity caused by Onchocerca volvulus infection by 2007; and (3) eliminate transmission of the parasite wherever feasible. Significant progress has already been made in all six countries, each of which has active programmes with treatment coverages exceeding the target of 85%. The progress is being documented in accordance with certification guidelines for onchocerciasis elimination established by the World Health Organization. No new cases of onchocercal blindness are being reported in the region, and ocular disease attributable to O. volvulus has been eliminated from nine of the 13 foci. Treatment is no longer needed in Santa Rosa, Guatemala, where transmission has been eliminated, and will be halted in at least three other foci in 2008, as they confirm the interruption of transmission. Treatment efforts should now be concentrated on the five foci where significant transmission remains: Central (Guatemala), Amazonas/Roraima (Brazil), North-central (Venezuela), North-east (Venezuela) and South (Venezuela). Based upon the experience gained, the well-established operations and the success achieved so far, it seems reasonable to estimate that onchocerciasis could be eliminated from most of the remaining foci in the Americas by 2012. The protocol, criteria and deadline for stopping all onchocerciasis treatment in the region should soon be addressed by OEPA's Program Co-ordinating Committee (PCC), in co-ordination with the PAHO.

Primeiro registro de simuliidae (Diptera) com polinários de asclepiadoideae (Apocynaceae) / First record of simuliidae (Diptera) with pollinaria of asclepiadoideae (Apocynaceae) attached

Polinários de duas espécies de Asclepiadoideae (Apocynaceae), possivelmente de Tassadia cf. martiana Decne. e T. cf. obovata Decne., foram observados pela primeira vez presos ao aparelho bucal de simulídeos [Cerqueirellum amazonicum (Goeldi), C. argentiscutum (Shelley & Luna Dias), C. oyapockense (Floch & Abonnenc) e Cerqueirellum sp.]. A frequência e distribuição dos insetos observados com polinários sugerem que esse tipo de evento não é casual. Os simulídeos devem buscar néctar nas flores de Asclepiadoideae, sendo capazes de remover seus polinários. Essa descoberta demonstra que os simulídeos não carregam apenas parasitas patogênicos, mas também polinários, e assim podem representar um grupo de polinizadores de espécies de Asclepiadoideae com flores pequenas.

The presence of pollinaria of two species of Asclepiadoideae (Apocynaceae), possibly Tassadia cf. martiana Decne. and T. cf. obovata Decne., attached to the mouth parts of simulid black flies [Cerqueirellum amazonicum (Goeldi), C. argentiscutum (Shelley & Luna Dias), C. oyapockense (Floch & Abonnenc), and Cerqueirellum sp.] are reported for the first time. The frequency and distribution of simulids recorded with pollinaria suggest that removal of pollinaria by these flies is not casual. Simulids probably use nectar in flowers of Asclepiadoideae as source of sugar, being able to remove their pollinaria. This finding demonstrates that simulids are not only vector of pathogenic parasites, but also carry pollinaria, and thus may represent a group of pollinators for species of Asclepiadoideae with small flowers.