SEARCH · PubMed Health

Results for “Mosquito 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 631 records · Page 35Linked to original sources

PubMed2001

Control of malaria vectors with the insect growth regulator pyriproxyfen in a gem-mining area in Sri Lanka.

The study was conducted in eight adjacent villages in central Sri Lanka where there are many shallow pits dug by gem miners that fill with water. These become breeding places of the main malarial vector Anopheles culicifacies, and of the second most important vector Anopheles subpictus, but not of Anopheles varuna, the third most important vector. With the help of local volunteers, data on the adult populations of these three species was collected by various standard methods, and data on the incidence of malaria cases was collected by two clinics set up for the project and through the existing hospitals. Prevalence of malaria infection in symptom-less people was investigated by mass blood surveys. On the basis of a year's pre-intervention data the villages were stratified into four with high levels of malaria transmission and four with lower transmission. Within each stratum two villages were randomly assigned for mosquito control by treating all the gem pits, as well as river bed pools, with a granular formulation of the insect growth regulator pyriproxyfen at a target dose of 0.01 mg a.i./litre. The intervention caused significant reductions in the adult populations of An. culicifacies and An. subpictus. Similarly, incidence of malaria was reduced in the intervention villages to about 24% (95% c.l. 20-29%) of that in the controls. Prevalence of parasitaemia also declined significantly. It is concluded that in this situation where, with active community participation, the breeding sites of the main vectors could be located; vector control by a highly active and persistent insect growth regulator can be a very effective means of malaria control.

Adolescent↗

PubMed2003

Bacteria in midguts of field-collected Anopheles albimanus block Plasmodium vivax sporogonic development.

Bacterial infections were investigated in midguts of insectary and field-collected Anopheles albimanus Weidemann from southern Mexico. Serratia marcescens, Enterobacter cloacae and Enterobacter amnigenus 2, Enterobacter sp., and Serratia sp. were isolated in field samples obtained in 1998, but only Enterobacter sp. was recovered in field samples of 1997 and no bacteria were isolated from insectary specimens. These bacteria were offered along with Plasmodium vivax infected blood to aseptic insectary An. albimanus, and the number of infected mosquitoes as well as the oocyst densities assessed after 7d. Plasmodium vivax infections in mosquitoes co-infected with En. amnigenus 2, En. cloacae, and S. marcensces were 53, 17, and 210 times, respectively, lower than in control mosquitoes, and the mean oocyst density in mosquitoes co-infected with En. cloacae was 2.5 times lower than in controls. Mortality was 13 times higher in S. marcensces-infected mosquitoes compared with controls. The overall midgut bacterial infection in mosquito field populations may influence P. vivax transmission, and could contribute to explain the annual variations in malaria incidence observed in the area.

Animals↗

PubMed1993

Evolution of resistance genes in absence of insecticide selection in a hypogeous population of Culex pipiens from the French Alps.

A monthly survey of resistance gene frequencies was conducted in a larval population of Culex pipiens breeding in an hypogeous site ("molestus" form) between July 1989 and September 1991, after interrupting mosquito control. Several significant variations in resistance gene frequency were observed. Some variations are explained by fitness differences between resistant and susceptible insects, others by an immigration of insects from the surrounding epigeous populations ("pipiens" form), which are highly resistant.

Acetylcholinesterase↗

PubMed2005

Insecticide-treated nets against malaria vectors and polystyrene beads against Culex larvae.

In Parasitology Today in 1985, Curtis and Lines, and Curtis and Minjas presented the ideas of insecticide-treated nets and polystyrene beads for mosquito control. The former idea has grown to be a major component of the strategy for malaria prevention, especially in Africa. However, although polystyrene beads have been demonstrated to work extremely well, they have yet to be taken up on a major scale.

Animals↗

PubMed2001

Evaluation of liquid Bacillus thuringiensis var. israelensis products for control of Australian Aedes arbovirus vectors.

Laboratory bioassay studies were conducted in southeast Queensland, Australia, on the efficacy of Teknar, VectoBac 12AS, and Cybate (active ingredient: 1,200 international toxic units Bacillus thuringiensis var. israelensis [Bti]) against 3rd instars of the arbovirus vectors Aedes aegypti, Ae. notoscriptus, Ae. vigilax, and Ae. camptorhynchus. Probit analyses were then used to determine LD50 (median lethal dose), LD50, and lethal dose ratios (LDR). Aedes aegypti and Ae. notoscriptus, both container-habitat species, tolerated the highest Bti concentrations compared with saltmarsh Ae. vigilax and Ae. camptorhynchus. For example, the LDR for Ae. vigilax versus Ae. notoscriptus exposed to Cybate was 0.14 (95% confidence limit [CL] 0.03-0.61). Similarly, the Cybate LDR for Ae. camptorhynchus versus Ae. notoscriptus was 0.22 (95% CL 0.07-0.70). Teknar produced similar results with an LDR of 0.21 (95% CL 0.04-1.10) for Aedes vigilax versus Aedes notoscriptus. Differences in product efficacy were found when tested against the 2 container-breeding species. Cybate was less effective than Teknar with LDRs of 1.55 (95% CL 0.65-3.67) and 1.87 (95% CL 0.68-5.15) for Aedes aegypti and Ae. notoscriptus, respectively. The significant differences in susceptibility between mosquito species and varying efficacy between products highlight the importance of evaluating concentration-response data prior to contracting with distributors of mosquito control products. This information is crucial to resistance management strategies.

Aedes↗

PubMed1988

Engineering, mosquitoes and filariasis: a case report.

The results of larval surveys were used to assess the relative numbers of mosquitoes breeding in different types of habitat and in different parts of the town of Pondicherry, India. The results illustrate an effective method to set priorities for mosquito control by identifying the most significant breeding sites in a town, and show that they are not necessarily the most obvious, the most extensive or those intuitively most likely.

Animals↗

PubMed2005

[Malaria prophylaxis for long-term travellers and expatriates].

Long-term travellers and expatriates are often non-compliant with malaria chemoprophylaxis due to a gradual neglect of the malaria risk combined with an unwillingness to take drugs for prolonged periods. The available regimes either have limited efficacy or are hampered by side effects, fears, cost and lack of data on long-term use. In order to prevent the dire consequences of malaria, we suggest tailoring the antimalarial strategy to the individual traveller. This requires balancing the risk of getting malaria, based on local transmission patterns, mosquito control and other factors, with the traveller's access to medical care and the options for chemoprophylaxis, the use of which in some cases may be limited to the rainy season or periods of travel to high-risk areas.

Antimalarials↗

PubMed2000

Public health implications of dengue in personnel returning from East Timor.

In north Queensland the vector of dengue fever (Aedes aegypti) is present; hence any viraemic individual importing dengue has the potential to transmit the disease locally. In early 2000 approximately 2,000 personnel returned from East Timor to Townsville, north Queensland. Seven importations of dengue occurred and individual cases were viraemic for up to 6 days in Townsville. No subsequent local transmission occurred. There were 3 cases each of dengue type 2 and dengue type 3. One case could not be serotyped. A response, including mosquito control measures, was initiated in another 18 cases in which dengue fever was clinically suspected but which subsequently proved not to be dengue. The planning and processes undertaken to prevent local transmission of dengue in Townsville during an intense period are described.

Dengue↗

PubMed1995

A North American model to contain the spread of Aedes albopictus through tire legislation.

The introduction, spread, and establishment of the Asian tiger mosquito, Aedes albopictus, in the United States has been facilitated by used or waste tires. This species has not only caused considerable concern among public health officials but also highlighted that the growing accumulations of used tires are a serious solid waste problem and a challenge to the recycling industry. This paper illustrates how the State of Illinois addressed the public health and solid waste problems associated with waste tires, mosquitoes and mosquito-borne pathogens. The goal of the State was to develop and implement through legislative process the Illinois Waste Tire Act. The purpose of the Waste Tire Act is: 1) to ensure that used and waste tires are collected for disposal and recycling, 2) to provide for the abatement of used and waste tire dumps and associated threats to public health, 3) to encourage the development of used and waste tire processing facilities and technologies, including energy recovery, and 4) to provide for research on vectors associated with used and waste tires, and the diseases they spread. The discussion will include key statutes from the Act and the model used to coordinate the effort of five different governmental agencies. An up-to-date presentation of vector-related research, mandated by the Act, ranging from applied investigations on mosquito control to more basic studies investigations on virus identification using molecular technology will be discussed. Finally a discussion of problems that have been encountered along with solutions dealing with legislative language, multidisciplined agency efforts and interactions with the general public are presented.

Adaptation, Physiological↗

PubMed2005

Immunologic responses to West Nile virus in vaccinated and clinically affected horses.

OBJECTIVE: To compare neutralizing antibody response between horses vaccinated against West Nile virus (WNV) and horses that survived naturally occurring infection. DESIGN: Cross-sectional observational study. ANIMALS: 187 horses vaccinated with a killed WNV vaccine and 37 horses with confirmed clinical WNV infection. PROCEDURE: Serum was collected from vaccinated horses prior to and 4 to 6 weeks after completion of an initial vaccination series (2 doses) and 5 to 7 months later. Serum was collected from affected horses 4 to 6 weeks after laboratory diagnosis of infection and 5 to 7 months after the first sample was obtained. The IgM capture ELISA, plaque reduction neutralization test (PRNT), and microtiter virus neutralization test were used. RESULTS: All affected horses had PRNT titers > or = 1:100 at 4 to 6 weeks after onset of disease, and 90% (18/20) maintained this titer for 5 to 7 months. After the second vaccination, 67% of vaccinated horses had PRNT titers > or = 1:100 and 14% had titers < 1:10. Five to 7 months later, 33% (28/84) of vaccinated horses had PRNT titers > or = 1:100, whereas 29% (24/84) had titers < 1:10. Vaccinated and clinically affected horses' end point titers had decreased by 5 to 7 months after vaccination. CONCLUSIONS AND CLINICAL RELEVANCE: A portion of horses vaccinated against WNV may respond poorly. Vaccination every 6 months may be indicated in certain horses and in areas of high vector activity. Other preventative methods such as mosquito control are warranted to prevent WNV infection in horses.

Animals↗

PubMed1989

Bacillus sphaericus as mosquito larvicide.

In Noorpur Shahan, a village in the outskirts of Islamabad, Bacillus sphaericus was tested to determine its efficacy against mosquito larvae. Since the creation of this new Islamabad district no mosquito control measure has been taken in the area and like so many other places in and around Islamabad, mosquito density is unusually high in this village. The efficacy of Bacillus sphaericus was studied upto seven weeks after its application and it gave good larval control.

Animals↗

PubMed1994

Pilot scale production and application in wildlife ponds of Lagenidium giganteum (Oomycetes: Lagenidiales).

Lagenidium giganteum, a facultative parasite of mosquito larvae, has recently been registered by the U.S. Environmental Protection Agency for operational mosquito control. We report here the first pilot scale production of the mycelium formulation. Scale-up from 10 to 650 liters was accomplished by a proportionate increase of medium components and volume of water. Foaming of the culture medium had not been encountered previously, but was a serious problem in pilot scale production due to the very rapid growth of a large volume of L. giganteum. Addition of an antifoaming agent did not adversely affect growth, but reduced the ability of the fungus to sporulate. Despite what was effectively a 100-fold reduction in the desired application rate due to reduced sporulation, L. giganteum infected sentinel mosquito larvae and reduced field populations for more than 2 months following application.

Animals↗

PubMed1998

"Reasons for contentment": malaria in India, 1900-1920.

Although Ronald Ross carried out his pioneering investigations on the role of the mosquito in the transmission of malaria in India, antimalarial activities in the sub-continent were disappointing. After the unsuccessful attempt at mosquito control at the military cantonment at Mian Mir (near Lahore, present day Pakistan), quinine prophylaxis was adopted as a compromise solution. While this strategy also failed, a good deal of important work was carried out in India in the first two decades of the twentieth century, so that by the 1920s, the magnitude of the malaria problem was fully appreciated.

Animals↗

PubMed1997

Cross-resistance to pyrethroid and organophosphorus insecticides in the southern house mosquito (Diptera:Culicidae) from Cuba.

A sample of the southern house mosquito, Culex pipiens quinquefasciatus Say, from Cuba was subjected to lambda-cyhalothrin selection to evaluate the usefulness of this pyrethroid insecticide for mosquito control. High resistance developed after 6 generations of selection. Little or no cross-resistance was observed to other pyrethroids (deltamethrin and cypermethrin), to a carbamate (propoxur) and to some organophosphates (chlorpyrifos and pirimiphos-methyl), but high cross-resistance was found to malathion (organophosphate). Possible resistance mechanisms responsible for this phenomenon are discussed.

Animals↗

PubMed2005

A mark-release-recapture study using a novel portable hut design to define the flight behavior of Anopheles darlingi in Belize, Central America.

Knowledge of the flight behavior of local vectors is of paramount importance in mosquito control programs. The following study defined the recapture rate of wild-caught, unengorged Anopheles darlingi females at 0, 400, and 800 m from a fixed release point in Belize, Central America, using a newly designed portable experimental hut. Three sampling trials, each consisting of 2 12-h collections, were performed at all distances from July 2002 to June 2003. A total of 1,185 An. darlingi were marked and released during the course of the study. The recapture rate was greatest at 0 m (29.0%; 124/428) and declined from 11.6% (37/318) at 400 m to 5.8% (21/361) at the 800-m site. There was no difference between the average number of marked mosquitoes recaptured inside the experimental hut versus outside the hut at any distance location. Recapture rates of each trial were highest during the first night's collection at all locations. Further examination of the first night data revealed a variation in the peak time of recapture by distances from the release point. The peak in nightly recapture at both the 0- and 400-m sites occurred within the first 2 h after sunset, and the peak recapture at the 800-m site occurred during the 7th h after sunset. Information from the present study is the first to describe the flight behavior of An. darlingi in Belize and will benefit in the development of adult-density risk assessments at the house level based on distances from potential vector breeding sites.

Animals↗

PubMed1990

Dengue serologic survey of schoolchildren in Rio de Janeiro, Brazil, in 1986 and 1987.

Two major epidemic waves of dengue 1 occurred in Rio de Janeiro, Brazil, in 1986 and 1987. This article reports the results of a survey of Rio schoolchildren who were tested serologically for antibodies to dengue 1 before and after the second major epidemic wave. The highest percentages of positive subjects were found in districts with relatively poor socioeconomic conditions and mosquito control problems. It also appears likely that the estimated number of dengue cases occurring in 1986-1987 was substantially below the number that actually occurred. In addition, because of this exposure to dengue 1, Rio de Janeiro now runs the risk of dengue hemorrhagic fever/dengue shock syndrome occurring should another dengue serotype be introduced within the next few years.

Adolescent↗

PubMed2003

Synergism between permethrin and propoxur against Culex quinquefasciatus mosquito larvae.

To see if synergism occurs between carbamate and pyrethroid insecticides, we tested permethrin and propoxur as representatives of these two classes of compounds used for mosquito control. Larvicidal activity of both insecticides was assessed separately and together on a susceptible strain of the mosquito Culex quinquefasciatus (Diptera: Culicidae) by two methods. When mixed at a constant ratio (permethrin : propoxur 1 : 60 based on LC50) and tested at serial concentrations to plot dose/mortality regression, significant synergy occurred between them (co-toxicity coefficient = 2.2), not just an additive effect. For example, when the mixture gave 50% mortality, the same concentrations of permethrin and propoxur alone would have given merely 2 x 1% mortality. When a sublethal dose (LC0) of permethrin or propoxur was added to the other (range LC10-LC95), synergism occurred up to the LC80 level. Synergistic effects were attributed to the complementary modes of action by these two insecticide classes acting on different components of nerve impulse transmission. Apart from raising new possibilities for Culex control, it seems appropriate to consider using such mixtures or combinations for insecticide-treated mosquito nets in situations with insecticide-resistant Anopheles malaria vectors.

Animals↗

PubMedDate not supplied

New strategy against Aedes aegypti in Vietnam.

The container-breeding mosquito, Aedes aegypti, is the major global vector of dengue viruses, causing around 50 million infections annually. We have developed a mosquito control strategy, incorporating four elements: (1) a combined vertical and horizontal approach that depends on community understanding; (2) prioritised control according to the larval productivity of major habitat types; (3) use of predacious copepods of the genus Mesocyclops as a biological control agent; delivered by (4) community activities of health volunteers, schools, and the public. We have previously reported that, from 1998 to 2003, community-based vector control had resulted in A aegypti elimination in six of nine communes, with only small numbers of larvae detected in the others. Here, we report eradication in two further communes and, as a result of local expansion after the project in three northern provinces, elimination from 32 of 37 communes (309730 people). As a result, no dengue cases have been detected in any commune since 2002. These findings suggest that this strategy is sustainable in Vietnam and applicable where the major sources of A aegypti are large water storage containers.

Aedes↗