SEARCH · PubMed Health

Results for “Insect Control”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,621 records · Page 90Linked to original sources

PubMedDate not supplied

The characterization of Leishmania parasites and their vectors from Central America using molecular techniques.

The disfiguring cutaneous and mucocutaneous and often fatal visceral forms of leishmaniasis are an increasing public health problem in Central America. There are some evidences of a highest prevalence of L. braziliensis and L. mexicana in Guatemala; L. braziliensis, L. panamensis and L. infantum (L. chagasi) in Honduras and Nicaragua, and L. panamensis in Costa Rica and Panamá. Our research project, just starting, attempts to use molecular approaches for a more rapid and accurate diagnosis and to identify the parasites. The techniques include non-radioactive DNA probes, PCR, schizodeme, isoenzyme analysis and monoclonal antibodies; and specific recombinant peptides will be used to improve immunodiagnosis of the visceral form. Intra-specific heterogeneity in Leishmania isolates will be examined by pulsed field electrophoresis and random amplified polymorphic DNA. Using selected strains, the techniques will be compared on a regional basis leading to a better knowledge of parasite distribution and the related clinical entities. Furthermore, DNA probes for the identification of parasites in vectors and for sibling species of vectors, are also to be applied; chemical identification of sandfly male pheromones will be attempted possibly leading to potential novel control measures.

Animals↗

PubMed1991

Reduction of transmission of shigellosis by control of houseflies (Musca domestica)

The effect of control of houseflies on the incidence of diarrhoea and shigellosis was evaluated in a prospective crossover intervention study at two military field bases several kilometers apart. In early summer, 1988, intensive fly control measures (mainly bait and trap strategy) were introduced on one base, while the other served as a control. After 11 weeks, as new cohorts arrived, the intervention was abruptly discontinued in the first base and instituted in the second for the next 11 weeks. The study was repeated the next summer. Overall, fly counts were 64% lower on the bases exposed to fly control measures (p = 0.024). Concomitantly, clinic visits dropped by 42% (p = 0.146) for diarrhoeal diseases and by 85% for shigellosis (p = 0.015), as did rates of seroconversion, by 76% (p = 0.024) for antibodies to Shigella and by 57% (p = 0.006) for antibodies to enterotoxigenic Escherichia coli. The findings indicate that houseflies, acting as mechanical vectors, transmit Shigella (and possibly enterotoxigenic E coli) diarrhoeal infections.

Adolescent↗

PubMed2004

Long-term, large-scale biomonitoring of the unknown: assessing the effects of insecticides to control river blindness (onchocerciasis) in West Africa.

The control of river blindness (onchocerciasis), a human disease transmitted by black flies, has been an economic and public health success in West Africa. It involved insecticide applications to as many as 50,000 km of rivers, almost weekly, in 11 countries between 1974 and 2002. The long-term biomonitoring of the effects of insecticide use on the nontarget invertebrate (primarily insect) and fish communities was initially designed on the basis of limited knowledge available for West African rivers and on information from other areas. Routine monitoring surveys demonstrated little effect on fish but produced inconclusive results for invertebrates. Research conducted beyond these surveys and current views in river and general ecology indicate that permanent damage to invertebrates from insecticiding was unlikely. The scientific progress made during the 29 years of this biomonitoring program is relevant to future, large-scale, long-term programs worldwide.

Africa, Western↗

PubMed2006

The Innovative Vector Control Consortium: improved control of mosquito-borne diseases.

Few new insecticides have been produced for control of disease vectors for public health in developing countries over the past three decades, owing to market constraints, and the available insecticides are often poorly deployed. The Innovative Vector Control Consortium will address these market failures by developing a portfolio of chemical and technological tools that will be directly and immediately accessible to populations in the developing world. The Bill and Melinda Gates Foundation has supported this new initiative to enable industry and academia to change the vector control paradigm for malaria and dengue and to ensure that vector control, alongside drugs, case management and vaccines, can be better used to reduce disease.

Animals↗

PubMed2001

Toxic effects of six plant oils alone and in combination with controlled atmosphere on Liposcelis bostrychophila (Psocoptera: Liposcelididae).

Six plant essential oils alone as repellent and fumigant, and in combination with the controlled atmosphere against Liposcelis bostrychophila Badonnel were assessed in the laboratory. These essential oils were extracted from the leaves of six source plants: Citrus tangerina Tanaka, Citrus aurantium L., Citrus bergamia Risso et Poiteau, Pinus sylvestris L., Cupressus funebris End]., and Eucalyptus citriodora Hook. The repellency test indicated that L. bostrychophila adults were repelled by filter paper strips treated with six essential oils. Of these essential oils, the C. funebris oil was most effective followed by that of F. sylvestris, C. tangerina, C. bergamia, and E. citriodora. The average repellency of the C. aurantium oil against L. bostrychophila adults was significantly lower than other five test oils by day 14. These essential oils had a high level of toxicity in the fumigation assay against L. bostrychophila adults at both 10 and 20 ppm. When combined with two controlled atmosphere treatments (12% CO2 + 9% O2, and 10% CO2 + 5% O2, balanced N2), the toxicity of plant oils was enhanced significantly.

Animals↗

PubMed2004

[Monitoring of canine leishmaniasis in northern Italy: an update from a scientific network].

Canine leishmaniasis (CanL) due to Leishmania infantum is a disease of great veterinary importance and a serious public health problem. In humans, L. infantum causes visceral (VL) and cutaneous leishmaniasis (CL) and the distribution of VL overlaps that of CanL. Currently, VL is considered by WHO as an emerging zoonosis in southern Europe. The dog is the only domestic reservoir of the infection and phlebotomine sandflies are the only proven vectors of leishmaniasis for dogs and humans. CanL is endemic in Italy, particularly in central and southern regions, including islands. Until 1983, all regions of northern Italy but Liguria and some territories of Emilia Romagna were considered free from CanL. From early '90s new stable foci of CanL have appeared, most of them located within classical endemic areas including territories of Emilia Romagna, Tuscany, Umbria, Marche, and Abruzzi regions. But the most relevant aspect, from an epidemiological point of view, has been the appearance of stable CanL foci in northern Italy, namely in Veneto and Piedmont regions. In these two foci, entomological surveys showed the presence of P. perniciosus and of a second phlebotomine vector, P. neglectus, which may have played a role in the CanL diffusion in some parts of northern Italy. Furthermore, in these areas, autochthonous human VL cases have occurred. There is therefore a realistic risk that CanL infection could rapidly spread through northern latitudes and a surveillance activity is strongly needed. For this reason, in October 2002, thanks to the collaboration and support of Intervet Italia, the network "LeishMap" was created, with the main purpose of monitoring the spread of CanL and vectors in northern Italy. LeishMap consists of scientific and sanitary institutions with proven experience both in field surveys and diagnostic methodologies on CanL and phlebotomine vector. It is organised in 4 Operational Units (OU), represented by researchers of the Veterinary Faculties of the University of Bologna, Padua, Milan and Turin, under the scientific coordination of the MIPI Department, ISS of Rome and with the collaboration of private and public veterinarians operating in the regions under study. During the first year of activity, each OU was involved in the serological and entomological surveillance of several territories in the respective regions, where recent autochthonous CanL cases were registered. The studies have involved five regions, namely Valle D'Aosta, Piedmont, Lombardia, Veneto, Trentino-Alto Adige and Emilia Romagna. In the Symposium 6 of this Congress we report detailed results of a retrospective analysis of data concerning CanL and vectors in northern Italy till 2002 and the preliminary results of 2003 on the seroprevalence rates observed in foci studied and on the entomological surveys carried out. In summary, the results outlined that already known foci of CanL are expanding from the original sites. Several new foci have been identified and many others are at high risk of evolving toward a stable endemicity. P. perniciosus has been found in all but one the suspected new foci. In Emilia Romagna region P. perfiliewi was identified in 2 areas and in one was the only species present. The occurrence of P. neglectus was confirmed in three regions, Veneto, Lombardia and Piedmont. In conclusion, from the 2002-2003 LeishMap activities it appears that further monitoring activities are necessary to identify new endemic foci of CanL, this representing the prerequisite for the implementation of programs for leishmaniasis control in northern Italy.

Animals↗

PubMed1986

Localized onchocerciasis vector control in the Bahr el Ghazal Region of South-Western Sudan. II. Control.

Onchocerciasis vector breeding along 41 km of the Bussere River in the Wau Area of South-Western Sudan was controlled with temephos (Abate) insecticide for one annual transmission period. Vector biting and transmission was compared to the two years of precontrol data. Up to 70% reductions in vector biting and 80% reductions in transmission were recorded at sites with the highest precontrol levels. The flies invading in the control year (principally those invading from the south-west in the main part of the rainy season) were found to be much less infective - 2390 fly bites would be needed to transmit 100 larvae in the control year, compared to 1490 in the precontrol years. It was concluded that localized vector control could have a major impact on onchocerciasis transmission and that in this, and many other foci in Sudan, permanent reductions could be achieved by causeway removal and selective vegetation clearance.

Animals↗

PubMedDate not supplied

Control of Bancroftian filariasis by integrating therapy with vector control using polystyrene beads in wet pit latrines.

In the town of Makunduchi, Zanzibar, wet pit latrines provided breeding places for Culex quinquefasciatus and there were few other mosquito breeding places available. The adult mosquito population in bedrooms was monitored for a year and found to consist almost entirely of Cx quinquefasciatus of which 2.45% carried infective larvae of Wuchereria bancrofti. It was estimated that each person received about 24,993 bites per year, of which 612 were potentially infective. After a year of baseline data collection, polystyrene beads were expanded in boiling water and applied to form floating layers on all infested pits. Subsequently the adult mosquito population declined remarkably so that the estimated number of bites per person per year was only about 439. To retain control, surveillance for newly wet pits continued to be necessary. Initially the microfilarial rate in the human population was 49.5%, with many cases of filarial disease. The microfilarial rate was reduced to 10.3% by mass treatment with diethylcarbamazine, with no sign of resurgence a year after treatment. The infective rate among mosquitoes was reduced to 0.41% and the combined effect of the vector and microfilarial control was to reduce the number of infective bites per person per year by 99.7%.

Adolescent↗

PubMed2006

Periurban Trypanosoma cruzi-infected Triatoma infestans, Arequipa, Peru.

In Arequipa, Peru, vectorborne transmission of Chagas disease by Triatoma infestans has become an urban problem. We conducted an entomologic survey in a periurban community of Arequipa to identify risk factors for triatomine infestation and determinants of vector population densities. Of 374 households surveyed, triatomines were collected from 194 (52%), and Trypanosoma cruzi-carrying triatomines were collected from 72 (19.3%). Guinea pig pens were more likely than other animal enclosures to be infested and harbored 2.38x as many triatomines. Stacked brick and adobe enclosures were more likely to have triatomines, while wire mesh enclosures were protected against infestation. In human dwellings, only fully stuccoed rooms were protected against infestation. Spatially, households with triatomines were scattered, while households with T. cruzi-infected triatomines were clustered. Keeping small animals in wire mesh cages could facilitate control of T. infestans in this densely populated urban environment.

Animals↗

PubMed1985

An overview of Culicoides control.

Although most of the research on ceratopogonid control has been directed at these biting flies as human pests, sufficient information is available to indicate the value of certain techniques in the suppression or control of bluetongue (BT) through Culicoides control. In areas where there is a limited number of larval development sites, larviciding or sanitation can be practiced by individual farmers or ranchers or by a small group of contiguous landowners. Where larval sites are more numerous or where large areas and many landowners are involved, vector control would need to be coordinated by a central agent or agency and would have to be coupled with other techniques aimed at the host animals or the virus into a totally integrated system of disease management.

Animals↗

PubMed1994

[The first 13 years of controlling Chagas' disease in Mambaí, Goiás, Brazil 1980-1992].

The Mambaí Project was launched in 1980 for the purpose of making a longitudinal clinical-epidemiologic study of Chagas' disease and of serving as a pilot program for the Ministry of Health of Brazil. At the beginning of the project, a census was carried out, the housing units were evaluated, and clinical examination and laboratory tests were performed on the population. After a phase of massive attack with insecticides, ongoing epidemiologic surveillance was instituted in order to detect residual foci of triatomine bugs in all the housing units in the municipality. The campaign included a program of health education combined with community participation. All infested housing units were selectively fumigated. In 1988 a new census was carried out, together with a serologic survey of children born after the control program was initiated. This article describes the results of epidemiologic surveillance during the first 13 years of the program. The prevalence of T. infestans in the housing units diminished to levels that suggest that vector transmission of the disease in Mambaí has been stopped. However, the risk of reinfestation from neighboring areas without control programs and the risk of colonization by secondary T. sordida vectors are factors that should be carefully monitored.

Animals↗

PubMed2003

Control trial of Lutzomyia longipalpis s.l. in the Island of Margarita, Venezuela.

The incidence of the American visceral leishmaniasis (AVL) in the Island of Margarita, a major tourist centre in Venezuela, has been increasing between 1998 and 2001. Lutzomyia longipalpis s.l. is the recognized vector, which was found naturally infected with Leishmania spp, indistinguishable from the parasites recovered from dogs and children. In 1999-2000, we conducted a control trial in Santa Ana del Valle and Las Cabreras, which have similar epidemiological and ecological conditions. The trial was based on intradomestic residual spraying of lambda-cyhalothrin, E.C., 25 mg/m2 and spatial fogging of fenitrothion around the houses at 30 g/ha. Sandfly abundance was recorded using Centers for Disease Control (CDC) traps indoors and outdoors. We found significantly reduced sandfly populations in the target locality. Wall bioassays showed that the residual effect of the insecticide lasts for about 3 months. We believe that indoor spraying with lambda-cyhalothrin three times a year, at a dose slightly greater than 25 mg/m2, might reduce the L. longipalpis s.l. population to a level low enough for achieving a significant reduction of the indoor transmission, thus protecting small children from the disease.

Animals↗

PubMed1998

Blackfly control: what choices after onchocerciasis?

Blackflies are reappearing in areas of West Africa where they used to be controlled with insecticides because they were vectors of the parasite Onchocerca volvulus. Even though they no longer transmit onchocerciasis in these areas they can hinder optimal land use through their biting behaviour. The authors discuss the problems associated with resuming the use of insecticides to control the blackfly and recommend that ground treatment be restricted to areas where it is likely to be effective on a continuing basis. In communities lacking technical and financial resources the only alternative consists of individual protection through the use of repellents or protective clothing.

Africa, Western↗

PubMed1998

Development of an indicator to evaluate the impact, on a community-based Aedes aegypti control intervention, of improved cleaning of water-storage containers by householders.

Householders in a community-based programme to control dengue in El Progreso, Honduras, are being encouraged to improve the cleaning of the water-storage containers in which many of the vectors thrive. The objective of the present study was to develop an indicator of the change occurring in human behaviour. Traditional Aedes aegypti larval indices do not differentiate between containers in which all the immature stages are present and those which hold only first- and second-instar larvae. However, it is not essential to prevent all larval development to limit transmission of pathogens by the adults; if the Ae. aegypti in the containers only manage to develop to young larvae before the containers are cleaned, then control of the vector in these containers will be effective. In field trials, sampling of third- and fourth-instar larvae in washbasins by taking five dips (quick immersions to a standard depth) with a hand-held net was found to be sufficient for estimating the true population size of that same cohort. This sampling method was then included in a large-scale survey of households, conducted for programme monitoring. An index was then developed as a summary measure of the degree of infestation of a washbasin by Ae. aegypti. This index was the sum of four variables assessed in the survey: presence of any immature stages (larvae and/or pupae); presence of pupae; detection of third-fourth-instar larvae in a five-dip sample; and a log-transformation of the number of larvae recovered. Based on this new index, the 884 washbasins encountered in the survey were classified as infestation-free (76.2%), or with low-(6.7%), medium-(14.9%) or high-level (2.2%) infestation. Application of the same procedure to 240 drums encountered in the survey showed that 66.3% were infestation-free and 9.2%, 17.1% and 7.4% had low-, medium- and high-level infestations, respectively. Compared with the traditional indices, this new index should be more sensitive to changes in human behaviour resulting from a control programme exposure than a simple, dichotomous variable (i.e. positive/negative for presence of immature stages). The use of such an index could make the control programme more efficient, allowing the greatest efforts to be targeted at households that have medium-high levels of infestation.

Aedes↗

PubMed2004

Control and eradication of African horse sickness with vaccine.

African horse sickness (AHS) is an infectious but no-contagious viral disease of equidae with high mortality in horses. The disease is caused by an arthropod-borne double-stranded RNA virus within the genus Orbivirus of the family Reoviridae transmitted by at least two species of Culicoides. Nine different serotypes have been described. The nine serotypes of AHS have been described in eastern and southern Africa. Only AHS serotypes 9 and 4 have been found in West Africa from where they occasionally spread into countries surrounding the Mediterranean. Examples of outbreaks that have occurred outside Africa are: in the Middle East (1959-1963), in Spain (serotype 9, 1966, serotype 4, 1987-1990), and in Portugal (serotype 4, 1989) and Morocco (serotype 4, 1989-1991). Laboratory diagnosis of AHS is essential. Although the clinical signs and lesions are characteristic, they can be confused with those of other diseases. Several techniques have been adapted for the detection of RNA segments, antibodies and antigen. Two types of vaccines have been described for AHS virus. Attenuated live vaccines (monovalent and polyvalent) for use in horses, mules and donkeys, are currently available, as well as a monovalent, serotype 4, inactivated vaccine, produced commercially but no longer available. New vaccines, including a subunit vaccine, have been evaluated experimentally. In this paper a review of the last AHS outbreaks in Spain, occurring during 1987-1990, and affecting the central and south part of the country, is presented. The role that vaccination played for the control and eradication of the disease, as well as other aspects such as climatological conditions, number of vectors and horse management, are also presented and evaluated.

African Horse Sickness↗

PubMedDate not supplied

[Control of Chagas' disease in Guarani communities: knowledge and hygiene habits within the Project to Improve Living Conditions in Bolivia].

The aim of this study was to identify knowledge and control of vectorial transmission (Triatoma infestans, known as vinchuca) of Chagas' disease in Guaraní Communities in Bolivia. We performed a descriptive study of a series of 98 individuals through a semi-structured questionnaire. Interviewees were asked about their familiarity with vinchuca, whether they thought vinchuca produced disease, the name of the disease and its consequences, as well as behavior related to eliminating the domestic insect vectors, such as cleaning of the home, backyard and corral.The insect vector was sufficiently well known (98%), although the name of the disease was identified by only 14.3% of the interviewees. Although the dwellings favored insect proliferation, they were not frequently cleaned: 28.6% cleaned their homes while and 42.9% cleaned the backyard and 7.1% cleaned the corral. Gender differences were found in the division of labor: women cleaned the homes and backyards, while men clean the corral. Experience has shown that the usefulness of projects for building healthy living areas and for health education depends on the value given to these projects by the community. Women are probably the best target group, because they perform a greater number of preventive tasks and seldom leave the community for extended periods of time.

Adolescent↗

PubMed2002

Seasonal variation in trachoma and bush flies in north-western Australian Aboriginal communities.

BACKGROUND: Among younger age groups trachoma (Chlamydia trachomatis) has been identified as a major cause of morbidity in Australian Aboriginal communities. North-western Australia has two seasons, referred to as the wet and the dry, and until recently most trachoma screening programmes were conducted during the dry season. This study compared the prevalence of trachoma between three Aboriginal communities, two in the west and one in the east Kimberleys with differences in adult bush fly (Musca vetustissima) populations between the wet and dry seasons. METHODS: All preschool and school-aged children in each community were screened for trachoma in February and July 1996 using the World Health Organization method for clinical assessment of trachoma. Flies were trapped fortnightly from September through to May (inclusive) using a wind-orientated fly trap. RESULTS: Two communities in the west Kimberleys had a significantly higher rate of trachoma during the wet season (14-59% in dry season compared with 46-69% in wet season). One community showed no difference but this was probably due to the reduced re-screening rate. Further-more, it was demonstrated that fly populations are so low during the dry season that they were untrappable; however, populations of bush fly significantly increased during the wet season (ranging from 6 to 146 flies per hectare per month). CONCLUSIONS: If bush fly populations are correlated with increased levels of trachoma, then measures aimed at augmenting public health plans for bush fly control may decrease the cross-infection rate. Additionally, based on the results of this study, wet season trachoma screening trips should be considered.

Animals↗

PubMedDate not supplied

[Data on a study of a natural focus of sandfly fever in Sevastopol during 1945-1988].

Sandfly [correction of Mosquito-borne] fever in Sevastopol was of a marked season character (June-September), with maximum cases registered in August. The morbidity curve corresponded to the sandfly [correction of mosquito] number curve, lagging behind it because of the incubation period. Since 1947 DDT and hexachlorane, having a lasting effect (40-50 days), have been widely used for sandfly [correction of mosquito] control. This was accompanied by intensive improvement of the living conditions in the city, regular sanitation and deratization. As a result of the above measures sandfly [correction of mosquito-borne] fever has not been registered in the city since 1954. The number of sandflies [correction of mosquitoes] reduced drastically, their species composition has changed: in 1959 sandflies [correction of mosquitoes] were found in 5.4% of the houses examined and in 1988, in 0.16% of houses. Since 1958 only 2 (Phlebotomus papatasii Scop and Ph. major Ann.) out of the former 7 species have been caught. Each species strives for self-preservation. Therefore, epidemiological survey of the former foci and sandfly-control [correction of antimosquito] measures are to be performed annually not to permit recovery of sandfly [correction of mosquito] population and repeated epidemics of sandfly [correction of mosquito-borne] fever.

Animals↗