cytoplasmic bridges within the follicular epithelium of the ovarioles of two diptera, aedes aegypti and stomoxys calcitrans.the cells of the follicular epithelium of the ovarioles of the mosquito, aedes aegypti (l.), and of the stable fly, stomoxys calcitrans (l.), have been found to be interconnected by cytoplasmic bridges. cytoplasmic bridges have been reported between sibling gamete cells of both male and female insects, but these bridges have not been previously reported to exist between somatic cells of insects.1977894721
studies on the attraction of aedes aegypti (diptera: culicidae) to man. 1977903926
population characteristics of domestic aedes aegypti (diptera: culicidae) in villages on the kenya coast i. adult survivorship and population size. 1977903935
population characteristics of domestic aedes aegypti (diptera: culicidae) in villages on the kenya coast. ii. dispersal within and between villages. 1977903936
aedes aegypti strain fitness for yellow fever virus transmission.three geographical strains of aedes aegypti from thailand (amphur), east africa (kampala), and the west indies (santo domingo) were compared for susceptibility to infection with low-passage yellow fever virus (french viscerotropic) as well as for ability to transmit virus by bite at varying extrinsic incubation periods. santo domingo strain appeared the most competent and kampala the least when mosquitoes were exposed to a low level virus-infecting blood meal; at higher virus levels, a similar t ...1977907058
the fate of ingested brugia pahangi microfilariae in susceptible and refractory strains of culex pipiens and aedes aegypti.the uptake and migration of microfilariae of brugia pahangi in susceptible and refractory culex pipiens and aedes aegypti were compared after membrane-feeding the mosquitoes on infected blood and anti-coagulant. there was no difference between the strains within each species in the pattern of migration, but in c pipiens only 24% of the microfilariae reached the thorax whereas in a. aegypti 73-6% were successful. in both susceptible strains the filariae in the thorax developed normally to maturit ...1977921369
a reduction in hospitalized cases of dengue haemorrhagic fever in menado (sulawesi), indonesia after aerial spraying with ulv malathion to control aedes aegypti. 1977925556
effects of gamma radiation on development of brugia pahangi in a susceptible strain of aedes aegypti. 1976957050
effect of host infection with plasmodium gallinaceum on the reproductive capacity of aedes aegypti. 1976965781
observations on the basal follicle numbers developed per female of two strains of aedes aegypti after being fed on hosts with different levels of microfilariae of brugia pahangi. 1976965782
effects of larval treatment with the insect development inhibitor ph60:40 on the vectorial capacity of aedes aegypti (l.) for brugia pahangi (buckley and edeson).the effects of ph60:40, an insect development inhibitor, on fourth instar larvae of aedes aegypti were investigated. apart from delayed lethal action, possible effects on the vectorial capacity of brugia pahangi were investigated. two strains of a. aegypti were used, one ddt-susceptible and a good filarial vector and the other ddt-resistant and a refractory vector. a baseline exposure was found which caused only low mortalities in both strains. the treatments did not have any appreciable effect ...1976971004
infection of an aedes aegypti cell line with infectious arbovirus-antibody complexes.aedes aegypti cells exposed to infectious complexes of wn or yf virus and homologous antiserum produced lower yields of virus over a 10-day observation period than were produced by aedes aegypti cells treated with a comparable dose of virus mixed with non-immune serum. when ae. aegypti cells were infected with wn virus mixed with mve, nta, den-2 or yf antisera the virus yield over 10 days was lower than in cell cultures infected at similar titres with mixtures of wn virus with non-immune serum. ...1976982518
endemic dengue virus infection in hispaniola. i. haiti.antibodies to group b arbovirus were common among coastal populations in the haitian part of the caribbean island of hispaniola. antibodies were present in 43% of children one to five years old; prevalence in older persons increased with age. in nine asymptomatic persons serodiagnostic changes indicative of group b arbovirus were detected during six of twelve consecutive months. in port cities where antibodies were common in children, aedes aegypti indices of 50%-70% were observed; in contrast, ...1976993618
infection of culicoides variipennis, culicoides nubeculosus, culicoides riethi and aedes aegypti with mansonella ozzardi. 19761006770
insecticide susceptibility studies in populations of aedes aegypti from maharashtra state, india. 19761024076
[detection of infusoria tetrahymena stegomyiae (keilin) in the larvae of culex pipiens molestus and aedes aegypti]. 19761025470
observations on the breeding habitats of aedes aegypti (l.) in jakarta, indonesia.a one-year study was done of the breeding habitats of aedes aegypti (l.) and of the water storage habits of the inhabitants in four crowded districts of urban jakarta. immature mosquitoes were found in or near houses in containers of relatively clean water used for drinking or bathing purposes. an average of 185 containers were found per 100 houses, of which 60 were positive for aedes immatures, resulting in a container index of 32%. the mean potential water storage capacity per house was 173 li ...19761030846
[results of a survey of potential dengue vectors in the neo-caledonian archipelago].the author gives the results of an entomological survey in neo-caledonian archipelago (new caledonia and loyalty islands), november-december 1972. concerning the distribution and the abundance of aedes aegypti, the local dengue vector, this study shows the presence of this culicid not only in noumea, but also all along the western developped coast of new caledonia, and in ouvea island. this constitutes a great risk of outbreak extension from noumea if a dengue virus is again imported there.19761036473
in vivo behavior of a sindbis virus mutant isolated from persistently infected aedes aegypti cell cultures.a mutant of the sindbis virus sv-s was found to interfere with the regular course of infection by the wild strain of the virus sv-w in a. aegypti mosquitoes and in suckling mice. in mosquitoes, this result was manifested by a reduced titer of sv-w in the presence of sv-s and by a failure of the mosquitoes to transmit sv-w. in the brains of suckling mice, in the presence of sv-s, the growth of sc inoculated sv-w was suppressed, and as a result, the usually lethal course of infection by this virus ...19751072594
infection of the mosquito aedes aegypti with infectious west nile virus-antibody complexes.aedes aegypti fed through chick skin membranes on west nile virus-homologous antiserum mixtures shown by an anti-globulin neutralization test to be highly infectious complexes (in terms of plaque formation in tissue culture) failed to become infected. control mosquitoes fed on west nile virus--normal rabbit serum mixtures containing similar or smaller amounts of infectious virus were shown to become infected. mosquitoes ingesting suspensions of west nile virus previously incubated with murray va ...19751080913
brugia pahangi: effects upon the flight capability of aedes aegypti. 19751149863
neutralization of sindbis virus by antisera to antigens of vector mosquitoes.sindbis virus harvested from infected cultures of vero cells and from aedes aegypti mosquitoes was used in neutralization tests with sera obtained from guinea pigs immunized with ground a. aegypti and from guinea pigs repetitively bitten by mosquitoes. employing these antisera, more mosquito-propagated virus was neutralized than was virus grown in cultures of vero cells. the neutralizing activity resided in the immune globulin fraction and may reflect the production of antibody to vector antigen ...19751155692
the multiplication of nodamura virus in insect and mammalian cell cultures.nodamura virus multiplied in mosquito cell lines, as determined by infectivivity assays in adult honey bees (apis mellifera) and wax moth larvae (galleria mellonella). titres of more than 10-7 and 10-5 bee ld50 /ml were obtained in culture fluids of aedes albopictus and aedes aegypti cells respectively after 10 days. comparable titres were obtained after several months, during which the cultures were subdivided up to six times. nodamura virus also multiplied in bhk cells and yielded titres of 10 ...19751168239
developmental effects of brugia pahangi (nematoda: filarioidea) to high temperature in susceptible genotypes of aedes aegypti (diptera: culicidae). 19751195293
arbovirus growth in aedes aegypti mosquitoes throughout their viable temperature range.after intrathoracic inoculation of laboratory-bred aedes aegypti mosquitoes with 3 yukon isolates of california encephalitis (ce) virus (showshoe hare subtype), northway (nor) and murray valley encephalitis (mve) viruses, viral replication was observed following incubation at 13, 21, 35 and 39 degrees c, which constituted the full temperature range of viability of a. aegypti. rates of viral replication were reduced at low temperatures and accelerated at high temperatures. virus-specific immunope ...19751202569
effect of the environmental conditions on eggs and water living stages of aedes aegypti (linn.) and aedes albopictus (skuse), vectors of dengue haemorrhagic fever in viet-nam. 19751203600
results of spraying with ultra-low-volume malathion at ground level in panama city.several ultra-low-volume (ulv) sprayings of technical malathion (95 per cent) were carried out in panama city. their purpose was to find out how useful this ulv technique could be in helping to combat mosquitoes, especially aedes aegypti. two residential areas were selected as sites for the trials. one of these was san francisco, a district near the shoreline of the bay of panama with many individual houses and a few tall buildings. the other was el cangrejo, a district further inland containing ...19751212538
observations on the re-establishment of aedes aegypti population in poona city and suburbs, maharashtra state, india. 19751213808
structure-activity relationships of phosphorus amides in aedes aegypti and culex pipiens fatigans (diptera: culicidae). 19751223296
distribution of aedes aegypti (linnaeus) and aedes albopictus (skuse) in small towns and villages of penang island, malaysia--an ovitrap ovitrap survey was carried out in april and may of 1975 at twenty-one locations scattered throughout penang island excluding the city of georgetown. the results showed the ubiquitous presence of ae. albopictus. ae. aegypti was recorded only in tanjung tokong lama, an area adjacent to the city of georgetown. in the survey, ae. albopictus females were found to prefer the outdoor ovitraps than indoor ones. the effectiveness of ovitrap in aedes survey was discussed.19751226538
vector competence of mosquitoes as a marker to distinguish central american and mexican epizootic from enzootic strains of venezuelan encephalitis virus.two epizootic strains of venezuelan encephalitis (ve) virus from central america and mexico were transmitted by a colonized epizootic vector mosquito, aedes taeniorhynchus, at higher rates than were two enzootic strains when the mosquitoes were infected by intrathroacic inoculation or feeding of virus. differences in transmission rates also occurred with colonized aedes aegypti, but were less marked. following intrathoracic inoculation of a. taeniorhynchus or a. aegypti, epizootic strains grew t ...19761259093
studies with brugia pahangi 12. the activity of levamisole.the effects of levamisole on adults, third stage infective larvae, and microfilariae of brugia pahangi were studied in in vitro culture and in vivo against developing stages in the vector mosquito and in infected cats. in vitro the drug was effective only at dose levels much higher than can be tolerated by mammals. it was active against the developmental stages of the worm in the vector aedes aegypti. the drug was strongly microfilaricidal in cats but less effective against adult worms.19761262689
[effect of the densonucleosis virus of the mosquito aedes aegypti l. on vertebrate animals]. 19761264036
the diel pattern of entry to outdoor oviposition sites by female aedes aegypti (l.) (diptera: culicidae) that then laid eggs there: a preliminary study.experimental observations, made outdoors during the dry and wet seasons in trinidad, demonstrate that more than 70% of female aedes aegypti that are destined to oviposit within the next two hours enter ovitraps during the first and last two-hour periods in the day, a finding consistent with the diel pattern of oviposition recorded earlier at the same site. it is possible that proportionately more eggs are laid in the morning peak during the dry season than the wet season. fewer eggs are laid wit ...19921288434
[the campaign against aedes aegypti]. 19921296682
[observation on the effectiveness of repellent coating against mosquitoes].the present paper reports on the effectiveness of a repellent coating for the first time. the repellent coating was made by combining deta (n,n-diethyl-meta-toluamide) with slow-releasing reagent. with this coating employed in the laboratory against aedes aegypti, the rate of blood-sucking was 3.9-9.5% and the rate of protection was 88.9-95.3% for 1-720 days. during 1-77 days' field trial, the rpi (relative population index) was 0-8.98% in the day-time and 0.74-17.15 during the night-time agains ...19921307278
susceptibility of selected strains of aedes aegypti and aedes albopictus (diptera: culicidae) to chikungunya virus.the relative susceptibility of selected strains of aedes aegypti (l.) and aedes albopictus (skuse) fed on a viremic monkey to infection with chikungunya virus was determined. infection rates were consistently higher in 10 strains of ae. albopictus tested than in 7 strains of ae. aegypti tested, regardless of the geographic location from which the strains originated or the dose of virus ingested. similarly, virus dissemination rates were higher in the ae. albopictus strains compared with the ae. ...19921313111
the complete nucleotide sequence of cell fusing agent (cfa): homology between the nonstructural proteins encoded by cfa and the nonstructural proteins encoded by arthropod-borne flaviviruses.cell fusing agent (cfa) is an rna virus originally isolated from a line of aedes aegypti mosquito cells. although our characterization of the virus many years ago showed that it resembled the flaviviruses, there was no detectable serological cross-reaction with members of the genus flavivirus. furthermore, unlike the well-studied members of the genus flavivirus, cfa did not replicate in any of several vertebrate cell lines tested. we have now determined the nucleotide sequence of the cfa genome. ...19921322586
enzymes in saliva from four parasitic arthropods.enzyme assays and sds polyacrylamide gel electrophoresis were carried out on saliva and in some cases homogenates of salivary gland and gut from four parasitic arthropods (the cattle tick, boophilus microplus (canestrini); the mosquito, aedes aegypti (l.); non-parasitic adult and parasitic larval blowfly of sheep, lucilia cuprina (wiedemann); the buffalo fly, haematobia irritans exigua de meijere). saliva from all species showed large differences in the number and molecular weight of components, ...19921330086
isolation of getah virus from mosquitos collected on hainan island, china, and results of a isolate of getah virus was obtained from culex mosquitos collected in mao'an village, baoting county, hainan province, china, in 1964. the virus (strain m-1) replicated in laboratory-bred aedes aegypti and cx. fatigans (= quinquefasciatus), and was transmitted by laboratory-bred ae. albopictus to healthy newborn albino mice. skeletal muscles of newborn albino mice experimentally infected with the virus showed degeneration, atrophy, necrosis, and inflammatory changes of muscle fibers. antibody ...19921338481
a new serotype of bacillus thuringiensis from colombia toxic to mosquito larvae.during a survey conducted in colombia a new isolate of bacillus thuringiensis that showed toxicity toward culex quinquefasciatus, cx. pipiens, aedes aegypti, and anopheles stephensi larvae was isolated. parasporal crystals were spherical in shape and showed a great degree of similarity with those produced by the reference strain of bacillus thuringiensis subsp. israelensis. supernatant fraction of the whole culture was not toxic, and heat-stable exotoxin production was negative. catalase, urease ...19921347310
[the efficacy of a combined preparation based on bacillus sphaericus and bac. thuringiensis h-14 against the larvae of blood-sucking mosquitoes].the optimal bactoculicide/sphaerolarvicide ratio in combination using against aedes aegypti larvae was established in laboratory by selection. the field trials of the selected bs/bt sample containing the ingredients in titer: bactoculicide-83, sphaerolarvicide-17 were conducted in the arid area of central asia. with 1 g/m2, complete mortality of culex, aedes and anopheles larvae was obtained with the residual larvicidal action of 15 days. it is recommended to carry out more large-scale trials of ...19921354836
comparison of bacillus thuringiensis subsp. israelensis cryiva and cryivb cloned toxins reveals synergism in vivo.when the gene for the mosquitocidal protein cryiva was expressed in two strains of bacillus thuringiensis (bt) cured of their resident delta-endotoxin genes, the protein accumulated as large inclusions. the inclusions produced in the bt subsp. kurstaki recipient strain were twice as soluble at alkaline ph as the inclusions produced in bt subsp. israelensis. solubilized protoxins were activated by treatment with mosquito gut extracts or trypsin for varying lengths of time and tested for in vitro ...19921355748
adulticidal effect of cyfluthrin against mosquitos of public health importance in malaysia.the efficacy of two formulations, wettable powder and emulsifiable concentrate, of cyfluthrin sprayed on plywood [10 mg (ai)/m2] was assessed against six species of mosquitos. the bioassay followed the who standard method, with some modification for the bioassay of insecticidal deposits on wall surfaces. the results indicated that these two formulations of cyfluthrin were effective against anopheles dirus and mansonia uniformis, moderately toxic to aedes aegypti and ae. albopictus in decreasing ...19921355928
infectivity and pathogenesis of iridescent virus type 22 in various insect hosts.this paper reports the results of a series of laboratory experiments to determine the infectivity and pathogenesis of iridescent virus type 22 (iv 22) for six species of mosquitoes, phlebotomine sand flies and triatomid bugs. following inoculation, iv 22 replicated in all of the species tested, without producing noticeable mortality within a 14 day observation period. examination of the infected insects by immunofluorescence demonstrated large amounts of viral antigen in many different organs. e ...19921355961
host range of clostridium bifermentans serovar. malaysia, a mosquitocidal anaerobic bacterium.clostridium bifermentans serovar. malaysia (c.b.m.) is toxic to mosquito larvae. in this study, we quantified its toxicity to the mosquitoes, aedes aegypti, ae. albopictus, ae. caspius, ae. detritus, anopheles stephensi, an. gambiae, culex pipiens and cx. quinquefasciatus. anopheles larvae are the most susceptible, followed by ae. detritus and ae. caspius, then culex and other aedes larvae. according to mosquito species, the lc50 varies from 7 x 10(3) to 1.3 x 10(6) cells/ml. three concentration ...19921357087
virus-dependent mortality in rift valley fever, eastern equine encephalomyelitis, and chikungunya virus-inoculated mosquito (diptera: culicidae) larvae.the effect of inoculation of mosquito larvae with rift valley fever (rvf) virus on survival to the adult stage was evaluated in aedes aegypti (l.), ae. fowleri (charmoy), ae. mcintoshi huang, ae. taeniorhynchus (wiedemann), ae. triseriatus (say), eretmapodites quinquevittatus theobald, anopheles albimanus wiedemann, and culex pipiens l. pupation rates were similar for rvf virus-inoculated and diluent-inoculated larvae of all mosquito species tested except cx. pipiens. however, with the exception ...19921357176
suppression of aedes aegypti by predatory toxorhynchites moctezuma in an island habitat.larval populations of the mosquito aedes aegypti were suppressed by predatory toxorhynchites moctezuma mosquito larvae released systematically in a village on union island (saint vincent and the grenadines) during march-december 1988. eggs and larvae of tx.moctezuma were transported from trinidad and introduced into all semi-permanent and permanent water-holding containers in the experimental village at clifton. the semi-isolated village of ashton served as control. base-line ae.aegypti indices ...19921358269
evaluation of the residual efficacy of permethrin-impregnated screens used against mosquitoes in marigat, baringo district, kenya.insecticide-impregnated screens and bednets are gradually finding wider use in malaria control programmes. the efficacy of these devices is dependent on the method of application, the acceptability by the people and effectiveness of the insecticide used. the present studies were carried out to determine the duration of the effectiveness of a permethrin-impregnated wall cloth (mbu cloth) used in the marigat area of baringo district, kenya in order to ensure its effective use. cotton cloth impregn ...19921363445
expression and secretion of a functional scorpion insecticidal toxin in cultured mouse cells.we have expressed a synthetic gene encoding the insecticidal neurotoxin of scorpion androctonus australis (aait) in nih/3t3 mouse fibroblast cells under the transcriptional control of a murine retroviral long terminal repeat. the secretion of the toxin into the culture medium was directed by the signal peptide of human interleukin-2. the recombinant aait produced was selectively toxic to yellow-fever mosquito larvae and harmless to mice.19901366462
characterization of a vasodilator from the salivary glands of the yellow fever mosquito aedes aegypti.salivary gland homogenates and oil-induced saliva of the mosquito aedes aegypti dilate the rabbit aortic ring and contract the guinea pig ileum. the vasodilatory activity is endothelium-dependent, heat-stable, sensitive to both trypsin and chymotrypsin treatments, and both smooth muscle activities cross-desensitize to the tachykinin peptide substance p. both bioactivities co-elute when salivary gland homogenates are fractionated by reversed-phase hplc. molecular sieving chromatography indicates ...19921375258
[effect of sublethal concentrations of abate on biological parameters of aedes aegypti].the effect of abate (temephos) applied at the rate of 0.016, 0.020 and 0.025 mg/l on fourth stadium larvae and its effect upon pupae weight, adult weight, ingested blood weight and longevity of aedes aegypti were investigated. the insecticide was applied on f2 generation larvae that were fed an artificial diet under laboratory conditions, from larvae collected at urban level in monterrey, n.l., mexico. in relation to the adult, females were fed with a 10 per cent honey solution and rabbit blood ...19921380186
larvicidal effects of penicillium citrinum spores and extracts upon aedes aegypti. 19921401991
seasonal incidence and horizontal distribution patterns of oviposition by aedes aegypti in an urban environment in trinidad, west indies.the oviposition patterns of aedes aegypti in ovitraps placed along 5 horizontal transects were monitored weekly for 52 wk (january to december 1988) in st. joseph, trinidad. of the 2,550 ovitraps exposed, 270 were lost and 1,177 (52%) out of 2,280 were used by gravid females, containing 38,118 eggs. during the dry season 43% (16,265 eggs) of the eggs were collected whereas during the wet season 57% (21,853 eggs) were collected. ovitraps exposed under eaves, under houses and in the open yard attr ...19921402866
mosquito vector control and biology in latin america--a second symposium.the second spanish language symposium presented by the american mosquito control association (amca) was held as part of the 58th annual meeting in corpus christi, tx in march 1992. the principal objective, as it was for the 1991 symposium, was to increase and stimulate greater participation in the amca by vector control specialists and public health workers from latin america. this publication includes summaries of 25 individual presentations that were given in spanish. the symposium included th ...19921402870
penetration of the mosquito (aedes aegypti) midgut wall by the ookinetes of plasmodium gallinaceum.we observed plasmodium gallinaceum ookinetes in both intracellular and intercellular positions in the midgut epithelium of the mosquito aedes aegypti. after epithelial cell invasion intracellular ookinetes lacked a parasitophorous vacuolar membrane and were surrounded solely by their own pellicle. thus, the ookinete in the midgut epithelium of the mosquito differs from erythrocytic and hepatic stages in that the parasite in the vertebrate host is surrounded by a vacuole. the midgut epithelial cy ...19921403980
experimental wuchereria bancrofti infection of culex quinquefasciatus and aedes aegypti.laboratory-derived females of culex quinquefasciatus and aedes aegypti were experimentally infected with wuchereria bancrofti by allowing the insects to feed on infected volunteers of known microfilariae density between 24.00 and 2.00 hours. of the 240 mosquitoes used for the experiments only 67 (55.8%) of c. quinquefasciatus and 83 (69.2%) of the ae.aegypti actually fed on the volunteers' blood. after 16 days post-infection period, 50 (74.62%) of the engorged c. quinquefasciatus harboured infec ...19921416219
development of specific ria and elisa to study trypsin modulating oostatic factor in mosquitoes.trypsin modulating oostatic factor (tmof), a decapeptide (h-ydpapppppp-oh) that signals the termination of trypsinlike enzyme biosynthesis in the mosquito midgut, was covalently bound to keyhole limpet hemocyanin using n-hydroxysuccinimide and dicyclohexylcarbodiimide. polyclonal antibodies raised in rabbits against this conjugate were used to develop specific ria and enzyme linked immunosorbent assay (elisa) to detect the peptide hormone in female aedes aegypti. tmof and its analogs tmof(b) (h- ...19921421442
plasmodium gallinaceum: antibodies to circumsporozoite protein prevent sporozoites from invading the salivary glands of aedes aegypti.a circumsporozoite protein-specific monoclonal antibody (n2h6d5) was injected into malaria-infected mosquitoes to determine its effect on the sporogonic cycle. after injection of antibody into mosquitoes (100 ng each), positive immunofluorescence (measured on air-dried sporozoites) reactions in hemolymph extracts were observed at a dilution of 1:1000. at 72 hr postinjection the levels dropped to 1:10. sporozoites coinjected with antibody did not invade the salivary glands. in naturally infected ...19921426132
influence of temperature on developmental parameters of the parasite/host system edhazardia aedis (microsporida: amblyosporidae) and aedes aegypti (diptera: culicidae).larvae of aedes aegypti, transovarially infected with edhazardia aedis, were reared between 20 and 36 degrees c to determine the influence of temperature on the development of the parasite and the infected host. development of the parasite was evaluated based on spore yield and size. the predicted optimum temperature for maximum spore production of e. aedis in a. aegypti was 30.8 degrees c. the results demonstrate that the e. aedis-a. aegypti system has a wide temperature tolerance; whereas spor ...19921431195
effect of per os edhazardia aedis (microsporida: amblyosporidae) infection on aedes aegypti mortality and body size.infection with edhazardia aedis uninucleate spores had less effect on aedes aegypti larval mortality and adult body size than did larval diet. larval mortality averaged 60-81% in starved larvae and 2-16% in well-fed larvae. no significant amounts of larval mortality could consistently be attributed to exposure to the parasite at dosages of 1.5 x 10(3) or 1.5 x 10(5) spores/ml. infection rates in adults surviving exposure to the parasites as larvae ranged from 30 to 59%. infected adults had signi ...19921431854
variation in aedes aegypti larval indices over a one year period in a neighborhood of mérida, yucatán, méxico.surveys for aedes aegypti larvae were conducted to provide an estimate of the magnitude and timing of seasonal variations in larval indices in one colonia in mérida, yucatán, méxico, and to assess how the proportion of disposable and non-disposable containers as larval production sites varies. breteau indices exceeded 200 during the months of july and august, and disposable containers were important year-round larval production sites.19921431864
[the susceptibility of mosquitoes for plasmodium gallinaceum in the joint use of biologically active substances].making use of a model pair aedes aegypti--plasmodium gallinaceum, the authors assess the susceptibility of mosquito female survivors to malaria agent after treatment of larvae with various bioactive substances. eight binary combinations of 6 preparations have been tried: dimilin and uvemon, insect development regulators; fundosol and copper sulfate, fungicides; phytobacteriomicin (pbm), a larvicidal antibiotic; bactoculicide, a bacterial agent. combinations of pbm with compounds differing by the ...19921435576
structure determination and toxicity of a new microcystin from microcystis aeruginosa strain 205.a new hepatotoxic microcystin was isolated from the cyanobacterium microcystis aeruginosa strain 205. its structure was found to be [dha7]microcystin-rr as determined by amino acid analysis, mass spectrometry and 1h nmr spectroscopy. ld50 value (i.p. mouse) of this toxin was 180 micrograms/kg. the 48 hr lethal concentration (48-hr-lc50) of the toxin for larvae of the yellow fever mosquito, aedes aegypti, was 14.9 micrograms/ml.19921440646
dengue 1 epidemic in french polynesia, 1988-1989: surveillance and clinical, epidemiological, virological and serological findings in 1752 documented clinical epidemic of dengue 1 occurred in french polynesia in december 1988 and june 1989. this paper records (i) the trend of the outbreak and its surveillance and (ii) the clinical, epidemiological and virological data obtained from 1752 documented cases. the epidemic reached its peak in february in tahiti island, 7 weeks after its recognition. among 6034 suspect cases reported by sentinel physicians, 60.3% were < 20 years old. the illness was classical dengue. no fatality or case of dengue haemorrh ...19921440788
evaluation of synergism among bacillus thuringiensis toxins.a simple test for synergism among toxins is described and applied to previously reported data on independent and joint toxicities of insecticidal proteins from bacillus thuringiensis. the analysis shows synergism between a 27-kda (cyta) toxin and 130- or 65-kda (cryiv) toxins from b. thuringiensis subsp. israelensis against aedes aegypti larvae. no positive synergism between 130- and 65-kda toxins or among three cryia toxins tested against seven species of lepidoptera occurred. comparisons with ...19921444368
opposite influences of host anaemia on blood feeding rate and fecundity of mosquitoes.we tested a theoretical model based on the physics of capillary flow and confirmed that anaemia accelerates blood intake in the yellow-fever mosquito, aedes aegypti (l.). we also investigated the influence of anaemic blood on egg production of mosquitoes and found that it has a negative influence on fecundity. based strictly on egg production and the physics of fluid intake, we propose that although anaemia associated with blood-borne parasites may be detrimental to mosquitoes that can engorge t ...19921454415
on the developmental velocity of wucheria bancrofti larvae in vector mosquitoes of different susceptibility to filarial infections.the developmental velocity of wucheria bancrofti larvae was investigated in mosquito strains with different susceptibility to this filarial species. high susceptibility of the vector strains favoured fast filarial development, e.g. between 17.1 and 25.9% of all discovered larvae on day 13 p.i. had already migrated to the head and mouth parts of the more and partly even highly susceptible anopheles gambiae, culex pipiens quinquefasciatus and aedes aegypti, respectively, whereas between 0 and 3.4% ...19921456467
binding of bacillus sphaericus binary toxin to a specific receptor on midgut brush-border membranes from mosquito larvae.the presence of specific receptors for bacillus sphaericus binary toxin on brush-border membrane fractions (bbmf) from culex pipiens larvae midgut cells was demonstrated by an in vitro binding assay. both activated and radiolabelled polypeptides from the 51-kda and 42-kda binary toxin of b. sphaericus 1593 specifically bound to bbmf. direct binding and homologous competition experiments indicated a single class of b. sphaericus toxin receptors, with a dissociation constant (kd) of approximately ...19921459140
female aedes aegypti (diptera: culicidae) in thailand rarely feed on sugar.female aedes aegypti (l.) of two different body sizes and provided with different diets (20% sucrose, water only, or 20% sucrose + human blood) were marked and released together in a rural thai village. recaptured marked and unmarked (wild) adults were tested for fructose by the cold-anthrone reaction. both released and wild females showed a low frequency of sugar feeding in nature; both small-bodied and large-bodied individuals failed to sugar feed significantly. marked females released with su ...19921460619
failure of dengue viruses to replicate in culex quinquefasciatus (diptera: culicidae).culex quinquefasciatus (say) and aedes aegypti (l.) were parenterally infected with dengue viruses and virus replication was monitored at intervals after infection in each species. dengue viruses replicated rapidly in ae. aegypti, reaching a peak titer of 10(6)-10(7) mosquito infectious dose 50 (mid50) per mosquito. in cx. quinquefasciatus, however, dengue virus replication did not occur. we conclude that this mosquito species is refractory to infection with dengue viruses and, therefore, does n ...19921460627
variation in the efficiency of vertical transmission of dengue-1 virus by strains of aedes albopictus (diptera: culicidae).five geographical strains of aedes albopictus (skuse) were compared for their ability to transmit vertically a dengue-1 isolate from jamaica. the oahu strain of ae. albopictus and a strain of aedes aegypti (l.) from the united states were included as controls. the offspring of orally infected females were assayed individually for vertical infection. vertical transmission rates among strains ranged from 11 to 41%, and filial infection rates of strains ranged from 0.5 to 2.9%. filial infection rat ...19921460640
the xxth century dengue pandemic: need for surveillance and the last decade of the xxth century aedes aegypti and the 4 dengue viruses had spread to nearly all countries of the tropical world. some 2 billion persons live in dengue-endemic areas with tens of millions infected annually. dengue pandemics were also documented in the xviiith and xixth centuries; they were contained by organized anti-aedes aegypti campaigns and urban improvements. the xxth century dengue pandemic has brought with it the simultaneous circulation of multiple serotypes and in ...19921462664
infection of adult mosquitoes by the entomopathogenic fungus erynia conica (entomophthorales: entomophthoraceae).the infection of adult mosquitoes by the entomopathogenic fungus erynia conica is presented for the first time. adult aedes aegypti were exposed to conidial showers from field-collected chaoborid, tipulid and chironomid cadavers for 24 h under conditions of 100% rh and 15 degrees c. up to 24% of the adults were killed by the mycosis. cadavers of ae. aegypti produced conidia that were infective to other adult ae. aegypti; however, rates of infection were never more than 12%. nevertheless, ae. aeg ...19921474381
mosquito size and multiple transmission of avian malaria in the laboratory.probing mosquitoes salivate before ingesting blood, and malaria sporozoites are transmitted during this phase of feeding. large and small aedes aegypti infected with plasmodium gallinaceum were allowed to probe briefly on a series of 3 naive chicks. large mosquitoes were more infective overall, but there was no difference in the ability of either size class to infect the first host. large mosquitoes were more likely than small mosquitoes to infect more than one host during serial feeding.19921474384
reduction in the susceptibility of aedes aegypti to brugia malayi infection after treatment with ethyl methanesulfonate.the susceptibility to brugia malayi infections of f2 and f4 progenies of aedes aegypti (black eye strain) treated with ethyl methanesulfonate (ems) was tested. both 3-day-old males and females were treated with 0.025, 0.050, 0.075 and 0.10% ems. control and treated females were then mated with normal or treated males to recover f1 progeny. f2 offspring were derived from sibling intercrosses, and 3 lines were established by further intercross matings to generate the f4. susceptibility in the 0.02 ...19921474390
[molecular cloning and identification of 130kd mosquitocidal protein gene of bacillus thuringiensis var. israelensis (bti)].the location of 130kd mosquitocidal protein gene of bti 4q5 strain on its 75md plasmid was confirmed by southern hybridization using a 18-base oligonucleotide probe. the crystal protein containing the component of 130kd toxic protein was purified. the crystal protein exhibiting the mosquitocidal activity against larvae of aedes aegypti was shown by bioassay. the purified 75md plasmid dna of bti 4q5 strain was completely digested with hindiii restriction enzyme, ligated with the vector puc18 and ...19921481529
further evidence that the genes controlling susceptibility of aedes aegypti to filarial parasites function independently.comparisons were made of in vivo labeled polypeptides from aedes aegypti strains refractory to either brugia malayi or dirofilaria immitis. there does not seem to be a generalized "anti-parasite" polypeptide response that mosquitoes refractory to filarial worm infection produce following bloodfeeding. instead, it seems that any response produced by these mosquitoes is localized to the tissue in which the filarial parasite develops.19921491306
multiple transmission of plasmodium gallinaceum (eucoccida: plasmodiidae) during serial probing by aedes aegypti (diptera: culicidae) on several hosts.mosquitoes salivate before ingesting blood, and sporozoites are transmitted during this phase of feeding. in the laboratory, malaria-infected aedes aegypti were allowed to probe on a series of three chicks during a 5-min period. probing on each host was interrupted after 10 s. our results demonstrate that up to three hosts can be serially infected with avian malaria during a 5-min period.19921495052
laboratory evaluation of brazilian mesocyclops (copepoda: cyclopidae) for mosquito laboratory tests, four different strains of mesocyclops aspericornis (daday) collected in or near fortaleza, brazil, showed potential as biological control agents of aedes aegypti (l.) mosquito larvae but were not as effective against anopheles or culex. in contrast, the larger m. longisetus (thiebaud), collected at fortaleza, killed 100% of ae. aegypti and anopheles farauti (laveran) (no. 1) at larval densities of 200/liter and culex quinquefasciatus (say) at 25/liter. in cage simulations wi ...19921495067
brugia malayi: ivermectin inhibits the exsheathment of microfilariae.brugia malayi-infected microfilaremic jirds (meriones unguiculatus) were treated with ivermectin at a single dose of 200 micrograms/kg of body weight injected subcutaneously. susceptible aedes aegypti mosquitoes were fed on treated jirds 24 hours later. mosquitoes fed on untreated jirds served as controls. infected mosquitoes were dissected at 1, 3, 24, 48, 72, and 96 hr after the blood meal, and differential counts of sheathed microfilariae, exsheathed microfilariae, and cast sheaths were perfo ...19921539753
dengue fever: a resurgent risk for the international traveler.the incidence of dengue fever, an acute febrile illness transmitted by the aedes aegypti mosquito, is on the rise. high fever, severe headache, skin rash and a variety of constitutional symptoms are hallmarks of classic dengue fever. dengue hemorrhagic fever, a severe manifestation associated with secondary infection, most often occurs in children. treatment of classic dengue fever is supportive, whereas urgent rehydration therapy is often required in more severe forms. community-based and perso ...19921543101
blood vessel location time by anopheles stephensi (diptera: culicidae).probing behavior of anopheles stephensi liston is characterized by the following: the first probe is longer than subsequent ones, the probability of blood location rises initially and then falls, and blood vessel location is deterministic. the overall probing behavior of an. stephensi, therefore, is similar to that of aedes aegypti (l.); i.e., differences between them were quantitative and may be accounted for by different levels of salivary apyrase and different experimental vertebrate hosts.19921552520
on the infectivity of early third-stage brugia larvae isolated from the abdomen of aedes aegypti.third-stage larvae (l3) of wuchereria bancrofti, brugia malayi and b. pahangi are known to be recovered not only from the head and thorax but also from the abdomen of dissected vector mosquitoes. for epidemiological reasons, was of interest to determine whether l3 larvae from the abdomen of the vector would be infectious for the final host. early abdominal l3 larvae of b. pahangi isolated as early as on day 7 post-infection (p.i.) from aedes aegypti were injected s.c. into five male meriones ung ...19921584752
developmentally regulated infectivity of malaria sporozoites for mosquito salivary glands and the vertebrate host.sporozoites are an invasive stage of the malaria parasite in both the mosquito vector and the vertebrate host. we developed an in vivo assay for mosquito salivary gland invasion by preparing plasmodium gallinaceum sporozoites from infected aedes aegypti mosquitoes under physiological conditions and inoculating them into uninfected female ae. aegypti. sporozoites from mature oocysts were isolated from mosquito abdomens 10 or 11 d after an infective blood meal. salivary gland sporozoites were isol ...19921588284
the role of the mosquito peritrophic membrane in bloodmeal digestion and infectivity of plasmodium species.secretion and luminal formation of the peritrophic membrane (pm) were induced in female anopheles stephensi and aedes aegypti by feeding the mosquitoes on a warmed suspension of latex particles in ringer's solution. the pm in a. stephensi was produced from apical secretion vesicles stored in the midgut epithelial cells and secreted into the lumen during feeding. in a. aegypti, the pm was formed de novo. when the latex feeding was followed 24 hr later by a meal of lyophilized pig blood, the 2 mos ...19921597785
biological control of culicidae with the copepod mesocyclops aspericornis and larvivorous fish (poeciliidae) in a village of french polynesia.the copepod mesocyclops aspericornis daday and the larvivorous fishes gambusia affinis (b. & g.) and poecilia reticulata r. & b., were released into mosquito breeding sites in tuherahera village, tikehau atoll, french polynesia, to control larvae of aedes aegypti (l.), ae.polynesiensis marks, culex annulirostris skuse and cx quinquefasciatus say. treatments were completed within a week, in january 1990. fish quickly eliminated mosquito larvae from the open breeding sites (ponds, wells). the impa ...19921600235
digestion of bacillus thuringiensis var. israelensis spores by larvae of aedes aegypti.the larvicidal activity of bacillus thuringiensis var. israelensis against mosquitoes and the blackfly is included in parasporal crystalline bodies which are produced during sporulation. following ingestion, the crystals are solubilized in the larval midgut and induce death within a short time; the spores germinate in the dead larvae and complete a growth cycle. the fate of the spores in surviving live larvae was elucidated by using a nonlarvicidal b. thuringiensis var. israelensis mutant. when ...19921607667
a novel bioassay system for evaluating the toxicity of bacillus thuringiensis israelensis against mosquito larvae.a bioassay system employing acutely toxic concentrations of a spore-crystal mixture of bacillus thuringiensis subspecies israelensis against fourth instar larvae of aedes aegypti (l.) is described. individual larvae are separately exposed to toxin in glass-lined miniature wells or scintillation vials. this method is free from the deaths due to predation among larvae. such larval deaths are commonly encountered in bioassay groups of 25 larvae as currently specified in the world health organizatio ...19921607671
phenol oxidase activity in hemolymph compartments of aedes aegypti during melanotic encapsulation reactions against microfilariae.monophenol oxidase (mpo) and diphenol oxidase (dpo) activity was assessed in hemocytes, cell-free plasma and complete hemolymph collected from aedes aegypti liverpool strain, intrathoracically inoculated with saline alone, immune activated by the inoculation of dirofilaria immitis microfilariae (mff), and uninoculated. enzyme activities between groups were compared using a radiometric hydroxylation assay (mpo) and a high pressure liquid chromatography with electrochemical detection assay (dpo). ...19921618354
results of a community-based aedes aegypti control program in merida, yucatan, mexico.this report describes the results of a community-based aedes aegypti control program in merida, yucatan, mexico. baseline surveys concerning knowledge, beliefs, and practices of 577 women and a larval survey of 616 house lots were carried out in october 1989. following development of a public health communication intervention from this data, the program was implemented in six communities. evaluation used an untreated control group design with pretest and two post-tests, one at completion and one ...19921621887
first reported outbreak of classical dengue fever at 1,700 meters above sea level in guerrero state, mexico, june outbreak of classical dengue fever occurred from march to august 1988 in the city of taxco, guerrero state, mexico. taxco is at an elevation of 1,700 meters above sea level, and this study represents the highest altitude at which an outbreak of dengue has been documented. an investigation was conducted to obtain serologic confirmation of dengue infection, determine the extent of the outbreak, and identify risk factors for dengue illness. toxorhynchites cell lines were used for viral isolation ...19921621889
induced polypeptides associated with filarial worm refractoriness in aedes aegypti.brugia malayi and wuchereria bancrofti are mosquito-borne parasitic nematodes responsible for lymphatic filariasis in approximately 90 million people. the genetic control of the susceptibility of aedes aegypti mosquitoes to b. malayi was well defined 30 years ago, but no data have since been provided regarding the gene products responsible for susceptibility or refractoriness or both. we addressed this problem by assessing polypeptide synthesis in thoracic tissue, the developmental site of this ...19921631149
[experimental research on the effect of biologically active substances on the susceptibility of mosquitoes to the causative agent of malaria. 3. algae, fertilizers].on a model pair aedes aegypti--plasmodium gallinaceum in has been shown that changes in the conditions of larvae development caused by the addition into the water medium of the live culture of synochocystis sp. cyanobacteria or green seaweeds chlorella vulgaris, acetone extracts from the live culture precipitate or chlorella powder, as well as nitrogen-containing fertilizer--ammonium chloride did not lower the sensitivity of the imago flying to malaria parasites. the results of the experiments a ...19911648659
genetic selection of a flavivirus-refractory strain of the yellow fever mosquito aedes aegypti.two inbred (isofemale) aedes aegypti mosquito lines were derived that manifested a resistant or susceptible phenotype following ingestion of yellow fever virus; lack of virus movement from the midgut defined the resistant phenotype. other flaviviruses, including dengue 1-4, uganda s, and zika, viruses behaved in a similar fashion in the two mosquito lines. crosses between the two lines produced progeny that were of intermediate susceptibility, indicating codominance; f2 backcrosses to the parent ...19911659238
in vitro development of brugia pahangi and brugia malayi in cultured mosquito vitro cultivation of brugia pahangi and subperiodic brugia malayi one-day old larvae to infective stage larvae (l3) within thoraces excised from aedes aegypti (black eye, liverpool) and anopheles quadrimaculatus was attempted. the mosquito thoraces were excised under aseptic conditions, 24 h after a blood meal on either b. pahangi- or b. malayi-infected jirds. the excised thoraces were washed aseptically and inoculated into a diphasic media. a nutrient agar base was overlaid with either grace ...19911671619
deletion by in vivo recombination shows that the 28-kilodalton cytolytic polypeptide from bacillus thuringiensis subsp. israelensis is not essential for mosquitocidal activity.the cyta gene encoding the 28-kda polypeptide of bacillus thuringiensis subsp. israelensis crystals was disrupted in the 72-mda resident plasmid by in vivo recombination, thus indicating that homologous recombination occurs in b. thuringiensis. the absence of the 28-kda protein in b. thuringiensis did not affect the crystallization of the other toxic components of the parasporal body (68-, 125-, and 135-kda polypeptides). the absence of the 28-kda protein abolished the hemolytic activity of b. t ...19911675212
[the specific nature of the irritability to fenitrothion and malathion in blood-sucking mosquitoes].several populations of malaria mosquitos were previously discovered to have different irritability to two insecticides of the organophosphorous group, such as fenitrothion and malathion. individual comparison of fenitrothion and malathion irritability levels in laboratory colonies of anopheles stephensi, an. atroparvus, culex pipiens, aedes aegypti, and ae. togoi and in the natural population of an. martinius has shown that irritability to the two chemicals is specific in all the six species. th ...19911676826
metabolites of fungi & actinomycetes active against mosquito larvae.extracellular secondary metabolites from 350 fungi and 94 actinomycetes were screened for larvicidal activity against culex quinquefasciatus, anopheles stephensi and aedes aegypti. of them, 133 fungal metabolites and 35 from actinomycetes were active. two from streptomyces sp. and one from paecilomyces sp. were highly active with lc50 value of 1-3 microliters/ml. the metabolites were more toxic to c. quinquefasciatus than to a. stephensi or ae. aegypti larvae.19911677347
comparison of four membranes for artificially bloodfeeding mosquitoes.four species of mosquitoes, aedes aegypti, ae. triseriatus, culex pipiens and cx. tarsalis, were allowed access to defibrinated rabbit blood via 4 different membranes and a standard membrane feeder. natural animal skins (mouse or quail) were the most effective. more than 50% of the aedes mosquitoes fed within 5 min and approximately 90% fed within 20 min on either mouse or quail skin. culex species fed best on quail skin, but the difference in feeding on quail skin and sheep intestine was not si ...19911680153
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