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At least 19 recordsLinked to original sources

Public health advantages of biological insect controls.

Biological control is not new, it is simply newly appreciated. This renewed appreciation stems from the widespread insecticide treadmill which is largely a product of insecticide disruption of the balance of insect communities. Biological control is a natural phenomenon; the regulation of plant and animal numbers by natural enemies. In this broad sense, biological control is vital to public health because it keeps the myriad insect species from out-competing us. It also has direct public health advantages as where natural enemies are manipulated to control disease vectoring insects. Insecticide distruption of biological control by insecticides and the resulting pesticide treadmill have serious public health implications. One is the increased pesticide load in the environment. The other is the acceleration of pesticide resistance in disease vectoring insects. The treadmill and its associated hazards will not abate so long as chemical control dominates our pest management strategy.

Environmental Health

Evaluation of functional degeneration of the amazon-ant Polyergus rufescens Latr. under an influence of socially parasitic way of life.

In certain, infrequently occurring, favorable circumstances the ants P. rufescens can display patterns of behavior which seem to be disappearing as a result of their parasitic way of life: the ability to food themselves, independently though ineffectively, elements of the offspring-protection behavior, transporting of nestmates, escape reaction. Similar events reinforce the infrequently used, latent reflexes, preventing their complete extinction. It is supposed that the characteristic in conventional parasitism disappearance of certain elements of behavior is inhibited by a social way of life. It may also be true of other, non-insect communities.

Animals

Impact of the black fly (Diptera: Simuliidae) control agent Bacillus thuringiensis var. israelensis on chironomids (Diptera: Chironomidae) and other nontarget insects: results of ten field trials.

Except for moderate mortality among filter-feeding chironomids, Rheotanytarsus spp., the results of 10 field trials with Bacillus thuringiensis var. israelensis (B.t.i.) indicated a wide margin of safety to the chironomid community and other stream nontarget insects. Mayflies, caddisflies and 2 other types of chironomids, i.e., tube-dwelling (Chironominae) and surface-dwelling, caseless larvae (mix of Chironominae, Diamesinae, Orthocladiinae, Tanypodinae), did not appear to be affected. The susceptibility of filter-feeding chironomids was considerably less than black flies; for example, 4 months of data collected during an operational black fly control program indicated a mean (+/- 95% CI) mortality among Rheotanytarsus larvae of 23 (15-32)% vs. 98 (97-99)% among black flies. Although clearly demonstrating the potential of adverse impact on filter-feeding chironomids in operational black fly programs, these trials also confirmed the narrow impact of B.t.i. on the overall stream insect community.

Animals

Bycatch in a bottle: what taxa are recoverable from metabarcoding DNA in historical invertebrate collection preservative fluid?

Natural history museum collections are invaluable repositories of biodiversity, offering insights into life on Earth. Genomic approaches provide powerful tools to characterize biodiversity in these collections. However using these collections for genomics without damaging specimens is a challenge. Here, we develop and test non-destructive DNA metabarcoding methods to capture biodiversity from the preservative fluids of archived insect collections ('Bycatch'). We optimized workflows for extracting and amplifying the partial CO1 locus (CO1) and fungal ITS1 locus from ethanol-based preservative fluids, validating ethanol preparation methods, comparing DNA extraction kits, and refining PCR protocols. Our results demonstrate that from museum collections with low DNA yields, CO1 and fungal ITS1 loci can often be recovered from preservative fluids, and we present detailed methodology and workflows. We test metabarcoding success to recover taxa in several museum collections ranging in age and storage condition. This is to support the State of California's effort to catalog and sequence all insects and fungi, building baselines of California biodiversity with help from museum collections. Lastly, we investigate the complementarity of metabarcoding water versus ethanol and morphological identifications aimed to capture benthic macroinvertebrate biodiversity in streams. Our findings highlight that DNA metabarcoding of the preservative fluid is a non-destructive tool for capturing biodiversity in historical specimens, but there are limitations on the overlaps between DNA results and physical contents, where morphological identification still reigns in taxon counts, but metabarcoding sometimes provides more taxonomic resolution, and can be used to track DNA from other organisms such as fungi beyond the directly surveyed specimens.

Animals

Food consumption patterns of the people of Dangamvura in Mutare.

The pattern of food consumption of people in Dangamvura, Mutare, was studied during January, May and August 1989. Most of the foods were consumed regularly throughout the year. Only four non-cultivated leafy vegetables and one insect were used by this community. The types of foods consumed were similar to those reported as being used in Mutambara.

Adult

[Aspects of "bug reporting" activity by the population in the control of Panstrongylus megistus in 12 countries of the northwestern region of São Paulo State, Brazil, 1974 to 1983].

The importance of "bug reporting", on the part of the local human population, to the epidemiological surveillance of Chagas' disease in S. Paulo State is demonstrated. The variations the number of "bug reports" from the local human population in the period from 1974 to 1983 relating to an area, infested by Panstrongylus megistus, in the northeast of S. Paulo State are studied. An increase in the number of "bug reporting" occurring in October, November and December was observed; however, no connection was discovered between domiciliary infestation rate and the "bug report" rate in this specific area.

Animals

[Entomological surveillance of Chagas' disease in the State of Sao Paulo].

Drastic modifications in agrarian space, with the reductions of primary forests, along with changes in rural production systems have led to the growth of salaried employment and also caused rural workers to move to the peripheral areas of cities. There has also been an intense and continuous intervention undertaken by the Superintendência de Controle de Endemias (SUCEN) through the use of pesticides in the fight against triatomine bugs in houses and peridomestic areas of the State of S. Paulo. All these factors have contributed to the interruptions of the natural transmission of Chagas' disease in S. Paulo. The next step in the program was the integration of vertical vector control into primary health care involving community participation. The several years of SUCEN's work among the rural communities has encouraged them to notify the presence of triatominae bugs, and prompt response to each notification has led to the growth of the process of permanent participation. Data from 1985 and 1986 showed that 85.6% of the bugs captured inside houses were notified by the population, which confirms that the best way to maintain the epidemiologic surveillance of Chagas' disease by the mobilization of local communities for effective participation in vector surveillance.

Animals

Community participation in vector borne disease control: facts and fancies.

The community involvement in solving their problems was spontaneous when the society as a whole had extensive control over the natural resources. However, this trend was lost during the industrial revolution when the social structure started disintegrating. Simultaneous discovery of antiparasitic drugs and powerful insecticides created a euphoria that all vector borne diseases could be controlled if not eradicated. Though the use of these tools resulted in control or eradication of vector borne diseases in many parts of the developed world, in poor developing countries the initial gains could not be sustained. This is partly due to non acceptance of technology by the beneficiary. Realizing that technology without the people is not going to solve the problem, the idea of community participation was revived. Since then, community participation has become a popular slogan and most programmes claim to have achieved community participation. The projects have not originated from the community and fail to differentiate between the gain achieved due to community effort and that due to the project personnel. The technical and material inputs provided are much higher than the national programmes can afford, carried out in limited areas for short periods and sustainability never demonstrated. Community participation in vector borne disease control has considerable potential specially in source reduction, reduction in man vector contact or accepting antiparasitic or antivector measures. True sustainable participation is possible only when the present trend of top-down planning is reversed to bottom-up planning; decision making power is handed over to the community; the people involved in conceiving, planning, implementation and evaluation of all developmental programmes and if the programmes are responsive to local needs and priorities.

Animals

Domestic triatomines (Reduviidae) and insect trypanosome infections in El Salvador, C.A.

Twenty-five Salvadoran communities have been surveyed to learn more about the distribution of Chagas' disease vectors and trypanosome parasites in that country. The results indicate that each of several factors--local variations in housing construction, insecticide applications, geographic elevation, and the vector species involved--can have a critical effect on transmission of the disease agent.

Altitude

[The supernatural, health and community action in Black Africa].

Based on the experience of community participation for tsetse control in the Congo, the author attempts to enlarge the reflexion on general health problems in Black Africa. He desires to draw the attention of the readers unfamiliar with anthropology, 1) to the current existence and social importance in the African communities of a particular approach, grounded on belief in the supernatural, radically different from Western thinking, 2) the intrinsic ambiguousness and richness of these ways of thinking, 3) to its great influence in community participation in sanitation programs. The ethical problems involved in the intervention of mediators using traditional or confessional ways of thinking are raised and included in a psychosocial problematic.

Animals

Coprophilous mite communities as affected by concentration of plastic and glass particles.

The community and trophic structure of mites was examined in cattle manure and their response to treatment of manure with solid-waste particles was investigated. Mites were collected from artificial dung pats exposed to natural colonization in the field for 16 days. The pats were composed of manure alone or manure separately mixed with waste-material particles of four types and concentrations. Mites were the numerically dominant taxon among arthropods in manure. The Prostigmata was the most abundant suborder, mainly represented by the families Pygmephoridae and Ereynetidae. The common families of Mesostigmata were all cosmopolitan. Correlations with other arthropods suggest that Mesostigmata are opportunistic predators, preying upon dipteran larvae, Collembola and other mites, and preyed upon by larger predatory insect larvae. Cryptostigmata and Astigmata were a numerically minor community component. The species composition and abundance upon treatment of manure with polyethylene, polystyrene and glass particles was similar to that of the treatment control, i.e. natural and inert sand. Relatively low concentrations, 5 and 30% (v/v), of particles in manure did not alter the mite communities despite important differences with untreated manure in final moisture content. These findings may be relevant to proposed methods of solid-waste disposal. High particle concentrations of 60 and 90% had detrimental effects to the abundance of mites in manure and were caused by the very low final moisture content and probably nutrient deficiency of these treatments. The persistence of members of the prostigmatid families Tydeidae, Nanorchestidae and Tarsonemidae in the moisture-deficient 90%-concentration treatments supports previous evidence of adaptations to low-water-content habitats.

Animals

Orchard netting impacts on biodiversity leading to cascading effects at the ecosystem level.

Agriculture must ensure food production without further compromising the ecosystem functions upon which it depends. Agricultural practices should therefore avoid harming farmland biodiversity, especially of taxa that supply the key ecosystem services (e.g. pollination, pest control and nutrient uptake) that ultimately support crop production. Orchards are among the largest permanent plantations worldwide and are increasingly characterised by the spread of plastic nets used to protect fruits/nuts from either abiotic (anti-hail, anti-rain, shade nets) or biotic (exclusion nets) hazards. Despite having received little attention to date, these nets may impact natural communities, acting both as physical barriers and as drivers of habitat changes to which biota must respond. Species-level responses to netting depend on the organism's ability to enter the netted environment and successfully exploit available resources. Net-mediated ecological filtering and plastic behavioural responses may alter species interactions, leading to cascading ecological impacts that may create species-poorer 'netted communities' with simplified ecological networks. Such changes may erode biological control potential, other ecosystem functions, and overall system stability. We conducted a systematic review on the effects of protection nets on biota, and reported novel empirical evidence on anti-hail nets' impacts on communities of orchard-dwelling birds, flower-visiting insects, and rodents. In total, we identified 48 studies from the literature, however this literature was strongly biased towards apple orchards, western countries, and pest taxa. Net deployment was highly effective in deterring target pest species, in some cases regardless of their original function, as even weather-protection nets limited pest populations. Side effects on non-target taxa were also often reported, such as decreases in pollinators and natural enemies, and/or increases in secondary pests or microbial diseases. However, most assessments largely disregarded non-pest taxa and the broader ecological consequences of netting. The few studies that addressed the effects of nets at the guild/community level, including our empirical study, confirmed that orchard netting resulted in species-poor assemblages, with possible ecosystem-level consequences. We propose that future assessments should pay more attention to the indirect effects of netting on non-target taxa, and on the supply of crop-supporting ecosystem services mediated by wild species occurring in agroecosystems. Due to the trade-offs between these services and net-mediated crop protection, integrated alternatives should be tested to improve the environmental sustainability of food production and biodiversity conservation in farmed landscapes.

Biodiversity

A new approach to community participation in tsetse control in the Busoga sleeping sickness focus, Uganda. A preliminary report.

A process is described by which trapping technology is being taught to a rural community which has been affected continuously by an epidemic of sleeping sickness for over a decade. Through a systematic health education programme, people are actively involved in making and setting traps and in learning about the general characteristics of the tsetse fly and the disease. A mono-screen trap has been developed for community use and is being used to trap flies. This is the first time that this kind of community participation has been attempted in tsetse control--and this approach is discussed in relation to other approaches.

Animals

Aquatic insects and trace metals: bioavailability, bioaccumulation, and toxicity.

The uptake of metals from food and water sources by insects is thought to be additive. For a given metal, the proportions taken up from water and food will depend both on the bioavailable concentration of the metal associated with each source and the mechanism and rate by which the metal enters the insect. Attempts to correlate insect trace metal concentrations with the trophic level of insects should be made with a knowledge of the feeding relationships of the individual taxa concerned. Pathways for the uptake of essential metals, such as copper and zinc, exist at the cellular level, and other nonessential metals, such as cadmium, also appear to enter via these routes. Within cells, trace metals can be bound to proteins or stored in granules. The internal distribution of metals among body tissues is very heterogeneous, and distribution patterns tend to be both metal and taxon specific. Trace metals associated with insects can be both bound on the surface of their chitinous exoskeleton and incorporated into body tissues. The quantities of trace meals accumulated by an individual reflect the net balance between the rate of metal influx from both dissolved and particulate sources and the rate of metal efflux from the organism. The toxicity of metals has been demonstrated at all levels of biological organization: cell, tissue, individual, population, and community. Much of the literature pertaining to the toxic effects of metals on aquatic insects is based on laboratory observations and, as such, it is difficult to extrapolate the data to insects in nature. The few experimental studies in nature suggest that trace metal contaminants can affect both the distribution and the abundance of aquatic insects. Insects have a largely unexploited potential as biomonitors of metal contamination in nature. A better understanding of the physicochemical and biological mechanisms mediating trace metal bioavailability and exchange will facilitate the development of general predictive models relating trace metal concentrations in insects to those in their environment. Such models will facilitate the use of insects as contaminant biomonitors.

Animals

Community participation in the control of tsetse flies. Large scale trials using the pyramid trap in the Congo.

An experiment of Glossina palpalis control was carried out by rural communities in 55 villages of the Niari river sleeping sickness focus (Bouenza region, Republic of the Congo). It was based on the use of a new trap, not requiring insecticide impregnation, in which the captured Glossina are preserved. The results show that this simple, cheap trap is an effective method of control, resulting in a considerable decrease in the tsetse population and is easily operated by the villagers. Screening surveys, using the indirect immunofluorescent test, conducted regularly in this focus, showed a decrease in the prevalence rate after the elimination of the flies. Long-term community participation is limited and must be improved by a better understanding of socio-cultural aspects and in certain cases must be associated with the work of a specialized team.

Animals

A simple vacuum dot-blot hybridisation assay for the detection of Drosophila A and C viruses in single Drosophila.

Specific cDNA clones were constructed from the single stranded RNA genome of Australian isolates of both Drosophila A and C viruses. These clones were used to develop a nucleic acid hybridisation assay capable of detecting reliably 3.9 ng of DAV and 19.3 ng of DCV virus particles, respectively. The sensitivity of the assays were largely unaffected by soluble host material. Single Drosophila naturally infected or artificially inoculated with DAV or DCV were found to contain in excess of 130 ng of virus. The results presented here demonstrate that the vacuum dot-blotting protocol and the hybridisation assays developed are capable of detecting DAV and DCV in single Drosophila and may therefore be applied to the study of DAV and DCV in natural Drosophila communities.

Animals