PubMed Health⌕ Search

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 649 records · Page 36Linked to original sources
PubMed2005

Aerial optimization and canopy penetration study of Dibrom 14 Concentrate.

This document describes the results of collaborative trials between St. Tammany Parish Mosquito Control, ADAPCO, Inc., and the Navy Disease Vector Ecology and Control Center, Naval Air Station, Jacksonville, FL. These tests provide data on the aerial optimization testing of Dibrom 14 Concentrate adulticide. During the week of June 17, 2002, 1 canopy penetration and 3 optimization studies were conducted in St. Tammany Parish, LA, using a Britton Norman twin turbine Islander equipped with 10-800067 flat fan nozzles. Dibrom 14 Concentrate (AMVAC Chemical Corp., Los Angeles, CA) was applied at 3.12 liter per min from a release height of 60.96 m above ground level (agl) at 140 kts indicated airspeed. This resulted in an application rate of 0.65 oz/acre.

Aircraft↗
PubMed2002

Persistence of dengue-3 virus through transovarial transmission passage in successive generations of Aedes aegypti mosquitoes.

Progeny of Aedes aegypti mosquitoes infected intrathoracically with dengue-3 virus was reared to subsequent generations. In each generation, blood-fed females were confined individually and the eggs obtained from the transovarially infected females were pooled. The seventh generation obtained from the infected parental mosquitoes showed that virus could persist in mosquitoes in successive generations through transovarial passage. The rate of vertical transmission initially increased in the few generations (F1-F2), but in subsequent generations it was found to be steady. Parental mosquitoes inoculated with virus showed higher mortality than the diluent-inoculated controls. There was an increase in the larval duration of transovarially infected batches at the seventh generation when compared with uninfected control mosquitoes. The fecundity and fertility of the transovarially infected batches of mosquitoes was also affected when compared with the controls. This is the first report demonstrating persistence of dengue virus in the successive generations of mosquitoes infected through vertical transmission. These observations, which have great epidemiologic importance, suggest that vector mosquitoes may play an important role in the maintenance of virus in nature, and that mosquitoes may act as reservoirs of these viruses.

Aedes↗
PubMed2005

Risk factors for infection during a dengue-1 outbreak in Maui, Hawaii, 2001.

Autochthonous dengue virus transmission, last identified in the state of Hawaii in 1945, was detected again in 2001. A seroepidemiological survey in a high-incidence community (Nahiku) and a nearby low-incidence community (Hana Subdivision) was implemented. The two communities studied differed in median household size (two vs. four persons), median lot size (2.8 vs. 0.8acres), proportion of households with mosquito larvae (81 vs. 28%) and incidence of recent infection (39% [28/72] vs. 1% [1/131]). The average number of reported anti-mosquito actions by residents of both locations remained low, and approximately 50% (42/80) of the inspected houses had larvae, evidencing the need for more effective community mosquito control. Logistic regression analysis of risk factors for infection in Nahiku identified residing in properties with birds in the house or yard as significantly associated with infection (odds ratio 7.0, 95% CI 1.7-28.5), probably as an indicator of unspecified environmental characteristics that were attractive to the vector. We documented that nearly 40% of Nahiku residents had acquired dengue locally in 2001 and that undetected dengue outbreaks had occurred in Hawaii. Our data suggest that ecological characteristics may help Hawaii health officials identify communities at increased risk of dengue infection.

Adolescent↗
PubMed1987

Effects of aerial thermal fog applications of fenthion on caged pink shrimp, mysids and sheepshead minnows.

Mosquito control applications of fenthion by aerial thermal fog equipment were studied at 2 sites in Collier County, FL, for sprays that occurred on June 20 and 23, 1984. Acute, lethal effects of fenthion deposited in these estuarine habitats were assessed for caged pink shrimp (Penaeus duorarum), mysids (Mysidopsis bahia) and sheepshead minnows (Cyprinodon variegatus). At Site 1, along a bay with substantial dilution and tidal mixing, fenthion concentrations of 1.5 and 0.29 micrograms/liter were measured in samples taken immediately after both sprays. Concentrations decreased to less than or equal to 0.020 microgram/liter 12 h postspray and no mortality was observed for caged pink shrimp and mysids. Site 2 was along a residential canal system that offered limited dilution and mixing. Maximum concentrations were 2.6 and 0.51 micrograms/liter and measurable concentrations (greater than 0.038 microgram/liter) of fenthion persisted at this site for 4 days. Fenthion concentrations in surface waters were toxic to caged pink shrimp and mysids after both sprays. No mortality occurred among caged sheepshead minnows at either site.

Animals↗
PubMed2000

Health complaints related to pesticide stored at a public health clinic.

Employees at a health center in Georgia were concerned that symptoms experienced by some employees were related to pesticide exposure at the center. Malathion and DDT, used for mosquito control from 1969 to 1981, had been stored and handled at the center's first floor. We surveyed 117 (91%) of 129 employees to determine whether reported symptoms were associated with pesticide exposure. We performed environmental sampling for pesticides. We analyzed serum samples for 17 chlorinated pesticides, and urine samples for malathion. We found that 37% of the participants had reported a diagnosis of sinusitis and 24% of bronchitis since working at the health center. Frequently reported symptoms were eye irritation (44%) and headache (68%). DDT and malathion were found at levels of 2.4 and 11%, respectively, in bulk samples from the loading dock of the building. Multivariate analysis of responses to the questionnaire showed that the perception of odors, inadequate air flow, and length of employment were significantly associated with the employees' health complaints. Pesticide concentrations in employees' serum and urine samples were not associated with any health complaint. The health complaints reported by the employees at the health center were precipitated by both environmental and psychological factors. The epidemiology and laboratory components of this study highlight the importance of obtaining biological measurements in episodes of perceived environmental exposure.

Adult↗
PubMed2004

Documentation of high-level bacillus Sphaericus 2362 resistance in field populations of Culex quinquefasciatus breeding in polluted water in Thailand.

Bacillus sphaericus (Bsph) Neide has been recognized as an effective mosquito larvicide since its discovery 20 years ago. Various strains of this agent, such as 2362, 2297, 1593, and C3-41, have been developed, formulated, and field-evaluated against mosquito larvae in different countries. Their high efficacy in controlling mosquitoes breeding in various habitats, especially those in polluted water, has been documented. However, resistance to Bsph has been reported in Culex pipiens complex in both laboratory colonies and natural populations. During our field trials on Bsph water-dispersible granules (WDG) against natural populations of Cx. quinquefasciatus Say in a low-income community, Nonthaburi Province, Thailand, control failure occurred within 4 months after 5 treatments using VectoLex WDG at the dosages of 50-200 mg/m2. The suspected Bsph-resistant Cx. quinquefasciatus mosquitoes were collected and colonized in the laboratory, from which the late stage larvae of generations F14 through F17 were used in bioassays to elucidate the resistance profile. A high level of Bsph resistance was documented in this colony as compared with the susceptible mosquitoes from the same area in Thailand or from California, USA. The resistance ratios (RR) at LC50, depending on reference colonies, were 21,100-28,100-fold against Bsph WDG or greater than 125,000-200,000-fold against Bsph technical-grade material. These Bsph-resistant mosquitoes, however, were completely susceptible to Bacillus thuringiensis var. israelensis, (Bti) preparations, LC50 ranging from 0.017 ppm for technical material with 7000 ITU/mg to 0.052 ppm for water-dispersible granules with 3000 ITU/mg. The RR to mixtures of Bsph + Bti in this highly Bsph-resistant mosquitoes increased steadily upon the increase of Bsph ratios in the mixtures from 50, 75, 90, 95 to 99%. The resistance levels to the mixtures with various ratios of Bsph and Bti, however, were substantially lower than that in Bsph alone, suggesting addition of Bti to Bsph substantially enhanced the mosquitocidal activity (synergism) against these highly Bsph-resistant Cx. quinquefasciatus. Moderate tolerance to low levels of resistance to Bsph/Bti recombinant (RR 7.29-12.75 at LC50 and 5.15-13.40 at LC90) was also noted in this Bsph-resistant population.

Animals↗
PubMed1994

Towards a new generation of flavivirus vaccines.

Flavivirus diseases have caused great public health concern for over three centuries, with diseases like yellow fever, dengue, Japanese encephalitis and tick-borne encephalitis causing thousands of deaths. Although yellow fever epidemics can be brought under control by the use of vaccine or mosquito-control measures, there have been many examples of its re-emergence as an epidemic disease. Similarly, the use of vaccines or arthropod-control measures have failed to prevent the spread of other flaviviruses such as Japanese encephalitis virus. There has been rapid growth in the knowledge of molecular information on flaviviruses in the last decade, and on the basis of this information several potential recombinant subunit vaccines are being developed and appear to be effective experimentally. Moreover, the assumption that humoral immunity induced by virus structural envelope glycoproteins is the only effective means of providing protection against flavivirus infection can be questioned. This review attempts to summarize recent thinking in this field and to evaluate the different systems available as potential future flavivirus vaccines in inducing protective immunity.

Flavivirus↗
PubMed1961

Population movements and problems of malaria eradication in Africa.

Population movements of various kinds are among the outstanding demographic features of the African continent and entail serious difficulties for malaria eradication. The majority of these movements are free and uncontrolled and are frequently inter-territorial in nature, hampering nation-wide or more limited malaria eradication projects and resulting in much reinfection.The author examines in some detail the types of population movements and their relationship to malaria problems in the Republic of Sudan, Ethiopia, Somalia, East Africa, Zanzibar, the Federation of Rhodesia and Nyasaland, Nigeria and Ghana. He concludes that these movements cannot be stopped and must be taken into account in planning malaria eradication programmes. More information on them and on the complex relationships between parasites, vectors and human beings is required, and inter-territorial co-operation is essential in obtaining this information and in planning.

Africa↗