[the ecology of dengue and aedes aegypti. preliminary investigation 4]. 19846084309
chemically-defined media for production of insect cells and viruses in vitro.two chemically-defined media are described. they support the growth of a) an established cell line of spodoptera frugiperda cells and b) two established mosquito cell lines from aedes aegypti and anopheles gambiae. the replication of autographa californica nuclear polyhedrosis virus (acnpv) in s. frugiperda cells grown in a defined medium is reported.19806102531
dengue hemorrhagic fever in malaysia: the 1973 epidemic.the first major malaysian epidemic of dengue hemorrhagic fever with severe manifestations occurred in 1973, with 969 reported cases and 54 deaths. in a detailed study of 138 clinically diagnosed and laboratory confirmed cases at the general hospital in kuala lumpur, hemorrhagic manifestations were observed in 68.7% and shock in 18.1% of the patients. the cases occurred mainly from may to september, largely in urban and suburban areas of the majority of the states in the country. a main focus of ...19806105712
potential vectors of malaria and dengue at townsville, queensland.a biting collection on the banks of ross river included anopheles farauti, adedes imprimens and ae. alboscutellatus, indicating a relict population of rain-forest mosquitoes and confirming two earlier records of an. farauti from townsville. aedes aegypti was collected at townsville airport. significance of these findings is discussed in relation to changing urban conditions and a proposed international airport.19806111741
[transovarial transmission of arboviruses by mosquitoes (author's transl)].an important aspect of the epidemiology of arboviruses is the manner in which the viruses are maintained during winter, dry season, or other adverse environmental periods when their arthropod hosts are inactive. one possibility is that the viruses survive in arthropods. in the case of mosquito-borne viruses, it is probable that such viruses could be maintained in this manner only if they were transmitted from one insect generation to the next by transovarial transmission. such transmission was r ...19816116146
[arbovirus diseases in south america and caribbean islands (author's transl)].historically, yellow fever has dominated arboviral diseases in south america and the caribbean and sylvatic cases still occur every year (more than 200 in 1979). the dengue, by the very large number of cases occurring in the area during successive epidemics--the most important being the last one in 1977-1978--is a serious problem for public health, an epidemic of hemorrhagic dengue being a constant threat. encephalitides are the third syndrome of arboviral etiology observed in the south american ...19816116149
[arboviral diseases in south-west pacific islands (author's transl)].islands of the south-west pacific area belong to the melanesian group, excepted niue, tonga, wallis and futuna which are polynesian. through new guinea, there is a geographic relation to the eastern part of australia, rich of 42 arbovirus types. dengue and ross river fever are the most important arboviral diseases in the region; both affect islanders after introduction of virus by travellers to localities where efficient vectors are present. dengue types 1, 2 and 4 were isolated from man and fro ...19816116150
the effect of 5-fluorouracil and 5-fluorocytosine on the development of the filarial nematodes brugia pahangi and dirofilaria immitis.5-fluorouracil and 5-fluorodeoxyuridine at 30 mg/kg body weight daily for four days inhibit microfilarial production in brugia pahangi in the jird. disruption of intrauterine embryogenesis was observed in treated female worms but the compounds were not macrofilaricidal or microfilaricidal under the conditions employed. 5-fluorocytosine possessed no filaricidal or embryostatic activity. the inhibition of microfilaria production by 5-fluorouracil was temporary and larval production was resumed wit ...19816118037
role of the parasporal body in causing toxicity of bacillus thuringiensis toward aedes aegypti larvae. 19826120198
[study of the larvicidal activity of bacillus thuringiensis var. israelensis on toxorhynchitinae larvae (author's transl)].toxicity of bacillus thuringiensis var. israelensis, h 14 serotype, has been tested on larvae of toxorhynchites amboinensis, predaceous larvae of other culicinae larvae. the toxorhynchites larvae are not sensitive to the bacterial toxin up to relatively high dosages, except when larvae of aedes aegypti are provided in the suspension. mode of action of the crystal appears to be similar to the one observed in the epithelial cells of intoxicated aedes aegypti larvae midgut.19826125271
ingestion and development of wuchereria bancrofti in culex quinquefasciatus, anopheles gambiae and aedes aegypti after feeding on humans with varying densities of microfilariae in tanzania. 19826126022
comparative bioassays of bacillus thuringiensis h-14 formulations against four species of mosquitoes in malaysia.comparative laboratory bioassays of three formulations of bacillus thuringiensis h-14 (ips-78, san 402-i and bactimos) were conducted against late 3rd/early 4th instar larvae of four species of mosquito, viz., aedes aegypti, culex quinquefasciatus, anopheles balabacensis and mansonia (mansonioides) indiana, in malaysia. from the average response of the mosquito larvae to the three formulations of b. thuringiensis h-14, ae. aegypti was found to be most susceptible, followed by cx. quinquefasciatu ...19826128794
the effects of parabiotic twinning of susceptible and refractory mosquitoes on the development of plasmodium gallinaceum.two species of mosquitoes were joined parabiotically with glass capillaries so as to share common hemolymph. in experiments designed to determine optimum physical factors was found that capillaries of 2.5 mm in length, 100 microns od and with pointed ends were tolerated best by mosquitoes and permitted optimum hemolymph transfer. maximum survival of mosquitoes was noted when capillaries were inserted in the post mesospiracular membranous area, in the largest mosquito first and allowed to fill wi ...19826129293
cultivation of mosquito cell lines in serum-free media and their effects on dengue virus mosquito cell lines from five species (aedes aegypti, ae. albopictus, ae. pseudoscutellaris, culex tarsalis, and toxorhynchites amboinensis) were adapted to three kinds of serum-free media (sem), which were composed of equal volumes of tryptose phosphate broth and of either leibovitz (l15) medium, eagle's minimum essential medium, or medium 199 with hanks' salts. population growth rates of the cells cultivated in the smfs were generally slower than those of original cell cultures maintaine ...19836137452
the biological control of aedes aegypti on sa-med island, rayong province by means of toxorhynchites splendens, a predatory mosquito larva. 19836138386
experimental model of transovarial transmission of tahyna virus in aedes aegypti mosquitoes.the progeny of 31 viruliferous aedes aegypti females infected with tahyna virus by sucking on viraemic newborn mice was investigated for virus presence. out of 1587 individuals of the f1 generation, 16 suspensions representing the progeny of 7 females were positive in 146 trials. individuals of the f1 generation failed to transfer the virus by sucking. electron microscopy revealed the presence of tahyna virus particles in the cytoplasm of maturing oocytes inevitably confirming the transovarial t ...19836138986
the importance of disease induced changes in mammalian body temperature to mosquito blood feeding.laboratory mice infected with rodent malaria (plasmodium berghei or p. chabaudi) or st. louis encephalitis virus (sle) were not hyperthermic during the infection period. however, all infected animals displayed pathogen-specific periods of hypothermia. hamsters infected with p. berghei were hyperthermic on day 7 postinfection (pi) but became hypothermic on day 8 pi and remained so until death, approximately 20 days pi. body temperatures of mice infected with p. yoelii were not significantly diffe ...19846142803
the effect of p-aminobenzoic acid and folic acid on the development of infective larvae of brugia malayi in aedes aedes aegypti mosquitoes, infected with the subperiodic brugia malayi, were found to enhance the development of the filarial parasites to the infective stage when they were exposed to a cotton pad soaked in 10% sucrose solution containing p-aminobenzoic acid (paba) in 0.001, 0.005, 0.01, 0.05 and 0.1% concentrations. similarly, larval development increased when the mosquitoes were fed with folic acid at 0.001, 0.01 and 0.1% concentrations. this stimulation was more when paba or folic acid ...19846143484
medium for the production of primary powder of bacillus thuringiensis subsp. israelensis.five media, formulated from the seeds of five legume varieties, dried cow blood, and mineral salts, were assessed for the growth and production of insecticidal properties of bacillus thuringiensis subsp. israelensis. bacterial powders prepared from the broth cultures were assayed against the larvae of aedes aegypti, culex quinquefasciatus, and anopheles gambiae. a standard primary powder of b. thuringiensis subsp. israelensis (ips78) was included in the assay for comparison. good growth was obta ...19846144290
[preliminary report on the susceptibility of mosquitoes to brugia pahangi].a comparative study on the susceptibility of eight species of four genera of mosquitoes to brugia pahangi was carried out. aedes aegypti (liverpool strain), aedes togoi, armigeres subalbatus and mansonia uniformis (taiwan strains) were found with the third-stage larvae 14 days after feeding on infected rats (sprague-dawley). the remaining of aedes aegypti, aedes albopictus, aedes pseudoalbopictus, culex p. fatigans and culex annutus (taiwan strains) were found refractory to infection. to determi ...19846150813
comparative bioassays of tolypocladium cylindrosporum gams (californian strain) against four species of mosquitoes in malaysia.comparative laboratory bioassays of tolypocladium cylindrosporum, california strain (kal) was conducted against third instar larvae of four species of mosquito, viz. aedes aegypti, anopheles balabacensis, culex quinquefasciatus and mansonia uniformis in malaysia. of the four mosquito species tested, ma. uniformis was found to be the most susceptible, followed by cx. quinquefasciatus, an. balabacensis and ae. aegypti, in a decreasing order. the lc50 values for ma. uniformis, cx. quinquefasciatus, ...19846151744
laboratory observations on toxorhynchites splendens wiedemann in thailand.the biology of toxorhynchites splendens predaceous larvae which breed in domestic containers like aedes aegypti was studied. egg stage lasts 52.64 +/- 0.13 hours. there are four larval instars lasting 2.38 +/- 0.04, 1.24 +/- 0.26, 8.09 +/- 1.6 and 28.78 +/- 5.39 days respectively. pupal development lasts 5.18 +/- 1.06 days. the adult life span is 29.55 +/- 8.06 days. growth increment was by measuring the size of head capsule. number of second instar prey larvae consumed by 1 to 4 instars predace ...19846151745
[research on viral infections in south pacific mosquitoes under natural conditions].from 1975, epidemiological studies on arboviral diseases, conducted in new caledonia, vanuatu, wallis and horne islands, have shown that 11 species of mosquitoes may harbour viruses in natural conditions. virus isolations were attempted from 1,025 pools of culicidae totalizing 32,182 individuals belonging to 5 genera and 21 species. viral infections have been demonstrated in 76 pools (7.4%). the species harbouring viruses were: aedes aegypti, ae. alternans, ae. notoscriptus, ae. vexans, ae. vigi ...19846151879
eradication of aedes aegypti on cayman brac and little cayman, west indies, with abate (temephos) in 1970-1971. 19826176286
toxicity of cyclic peptide antibiotics to larvae of aedes aegypti. 19836196417
[the initial activity and persistance of an experimental larvicide with a base of bacillus thuringiensis var. israelensis and a commercial preparation containing the organophosphorus insecticide temephos].the larvicide activity of the experimental preparation san 402 i wdc containing b. thuringiensis var. israelensis and that of abate 500 e (44 % temephos) were tested on the larvae of aedes aegypti. the studies were performed on the following media: distilled water, pure and buffered at ph 9, 7 and 4 and pond water whether or not free from materials in suspension. the activity of both preparations is not influenced by the composition of the media, exception made for the presence of materials in s ...19846208235
transovarial transmission of murray valley encephalitis virus by aedes aegypti (l).in laboratory studies, murray valley encephalitis virus was transmitted transovarially by orally infected aedes aegypti to approximately 1.5% of both adult male and female progeny.19806263238
zika virus, a cause of fever in central java, 1977 and 1978 selected in-patients at the tegalyoso hospital, klaten, indonesia who had recent onsets of acute fever were serologically studied for evidence for alphavirus and flavivirus infections. a brief clinical history was taken and a check list of signs and symptoms was completed on admission. acute and convalescent phase sera from 30 patients who showed evidence that a flavivirus had caused their illnesses were tested for neutralizing antibodies to several flaviviruses which occur in s ...19816275577
the measurement of blood meal size in aedes aegypti (l.).three techniques of estimating blood meal volumes (gravimetric, radioisotope counting and haemoglobin estimation) were compared in adult female aedes aegypti fed on a cat. aedes aegypti ingested a mean volume of 2.37 ul, 2.44 ul and 2.57 ul as measured by gravimetric, radioisotope and haemoglobin estimation techniques respectively. this difference was not statistically significant (p greater than 0.05, n = 58). neither calendar age (post-eclosion) nor strain differences appear to influence blood ...19806282090
[reproduction of powassan and west nile viruses in aedes aegypti mosquitoes and their cell culture]. 19826289063
specificity of cultured insect tissue cells for bioassay of entomocidal protein from bacillus thuringiensis.cultured tissue cells from lepidopteran and dipteran sources displayed an order-specific response to entomocidal protein from crystals of bacillus thuringiensis. protein isolated from crystals of b. thuringiensis subsp. kurstaki was effective against cells of the spruce budworm (choristoneura fumiferana) and the tobacco hornworm (manduca sexta), but was inactive against both mosquito cell lines tested (aedes aegypti and anopheles gambiae). conversely, protein from inclusion bodies of b. thuringi ...19846321329
a survey of filariasis among refugees in south florida.between january 1981 and march 1982, a filariasis survey was conducted among 668 haitian immigrants and 155 southeast asian refugees residing in florida, u.s.a. microfilariae were detected only in haitians, with 6.7% positive for wuchereria bancrofti and 1.3% positive for mansonella ozzardi. the majority of individuals with bancroftian filariasis came from five coastal urban areas including port-au-prince, duvalierville, gonaïves, leógane and cap-haitien. no unequivocal signs of bancroftian fila ...19846370004
[ecology of dengue and aedes aegypti. preliminary study]. 19846372125
selective primary health care: strategies for control of disease in the developing world. xi. dengue.since world war ii, dengue viruses have progressively extended their geographic domain and have increased as causes of human morbidity and mortality. this complex of four flaviviruses is principally transmitted to humans by the bite of aedes aegypti, the yellow fever vector. factors that promote the indoor storage of water are congenial to the breeding of a. aegypti. these include the dislocations of wars, overpopulation , and urbanization. by the mid-20th century, a. aegypti eradication campaig ...19846374837
arthropod studies with rabies-related mokola virus.a cell culture-adapted variant of the rabies-related mokola virus was demonstrated to replicate in inoculated aedes aegypti mosquitoes. replication was slow compared to many arboviruses in their vectors. maximum titers were not obtained until after approximately 6 weeks of extrinsic incubation. mokola virus underwent nine mosquito-mosquito passages at approximately monthly intervals and was thus maintained in insects for 340 days before terminating the study. virus antigen was detected by immuno ...19846385743
the use of dragonfly nymphs in the control of aedes aegypti.the predatory rates of the dragonfly nymphs on aedes aegypti were studied in the laboratory and under field conditons. labellulid nymphs were found to predate on ae. aegypti larvae and pupae readily. the rate of consumption was found to be 133 +/- 21 all stages of larvae per medium size nymph per 24 hours. in container habitats complete elimination of all larvae and pupae were achieved between day 4 and 9 depending on density of aquatic stages. the dragonfly nymphs as predators could be used in ...19806447358
[comparative action of solubilized crystals of h-14 and h-1 serotypes of bacillus thuringiensis on cultures of aedes aegypti cells].crystals isolated from bacillus thuringiensis serovar thuringiensis (h-1) and from serovar israelensis (h-14) were dissolved in sodium hydroxide, then tested in vitro on aedes aegypti cell cultures. toxic action was followed after morphological and metabolic alterations of the treated cells. only the israelensis sodium extract was toxic and gave cellular swelling, inhibition of cell growth and inhibition of labelled precursor incorporation, i. e. of 3h-thymidine, 3h-uridine and 3h-leucine.19846465742
[the ecology of dengue and aedes aegypti. preliminary report. 3]. 19846474264
the effect of colonization upon aedes aegypti susceptibility to oral infection with yellow fever virus.two colonies of aedes aegypti were established from two independent collections from vero beach, florida. eleven sequential generations of the first colony were tested for variation in oral susceptibility to infection with yellow fever virus (yfv). each generation was also assayed for genetic variability at seven enzyme loci using electrophoretic techniques. significant differences in infection rates were detected between some generations. these differences were significantly correlated with gen ...19846476217
the verification of a mammalian toxicant classification using a mosquito screening method.routine toxicity screening of substances using rodents can be time consuming and expensive. for these reasons various alternative methods have been developed, but many lack standardization and acceptance. it was hypothesized that a satisfactory classification of mammalian toxicants could be obtained using a simple mosquito (aedes aegypti) screening method. to this end, median lethal concentration (lc50) values were determined for a wide variety of mammalian toxicants representing a range of toxi ...19846519371
[fecundity of aedes aegypti mosquitoes in relation to their infection with the malaria agent plasmodium gallinaceum].studies of the effect of p. gallinaceum on ae. aegypti in different periods of the agent's sporogony and during different gonotrophic cycles of the vector have shown the absence of strong inhibition of mosquitoes' fecundity.19846522100
comparative development of brugia malayi in susceptible and refractory genotypes of aedes aegypti. 19846527177
infectivity of a venezuelan strain of metarhizium anisopliae to aedes aegypti larvae. 19846539354
natural transovarial transmission of dengue 4 virus in aedes aegypti in trinidad.the isolation of dengue 4 virus from adult aedes aegypti, reared from eggs collected in nature, is reported for the first time. from the locality where the isolate was made, 25 pools consisting of 1,848 ae. aegypti reared from eggs were processed. in this study, 10 different localities were sampled and a total of 10,957 ae. aegypti adults, collected as eggs or larvae in nature, were processed for virus isolation. from a total of 158 mosquito pools tested, one recovery of dengue 4 virus was made. ...19846542323
[laboratory study of the transmission of dengue virus by aedes aegypti and aedes albopictus]. 19846543740
the regulation of preimaginal populations of aedes aegypti (l.) (diptera: culicidae) on the kenya coast. ii. food as a main regulatory factor.experiments were carried out in a village on the kenya coast to investigate observed differences in pupal productivity of aedes aegypti breeding in indoor pots. daily addition of maize gruel, the staple food of villagers, to pots of high and low mosquito production promoted an increase of pupal numbers, although daily introduction of first-instar larvae did not significantly affect pupal production. differences in pupal productivity were not related to differences in the numbers of eggs laid in ...19846547039
development of dirofilaria repens in aedes aegypti reared in contrasting habitat.the susceptibility of dirofilaria repens infection in aedes aegypti adults reared in hay-infusion and tap-water during their larval stages was tested. ae. aegypti reared in hay-infusion ingested a bigger amount of blood than those reared in tap-water but harboured fewer d. repens larvae (developing and arrested). the difference in the susceptibility of mosquitoes from the two treatments was correlated with the difference in the robustness of the mosquitoes.19836612416
breeding of aedes aegypti in closed septic tanks. 19836618537
transovarial transmission of dengue viruses by mosquitoes: aedes albopictus and aedes aegypti.transovarial transmission of all four dengue serotypes was demonstrated in aedes albopictus mosquitoes. the rates of such transmission varied with the serotype and strain of virus. in general, the highest rates were observed with strains of dengue type 1 and the lowest with dengue type 3. surprisingly, despite the use of viral strains of the four dengue serotypes which gave the highest rates with ae. albopictus, transovarial transmission was observed in aedes aegypti only with dengue type 1, and ...19836625066
toxicity of bacillus thuringiensis subsp. israelensis to adult aedes aegypti female aedes aegypti mosquitoes were killed by the parasporal crystals of bacillus thuringiensis subsp. israelensis (onr-60a) when the crystals were introduced into the insect midgut as an enema. the 50% lethal dose for intact parasporal crystals was 0.21 microgram/mg of mosquito (wet weight), and for solubilized crystals the 50% lethal dose was 0.04 microgram/mg. these values were compared with 50% lethal concentrations in a free-feeding larval mosquito bioassay of 0.018 and 1.28 microgra ...19836625566
the problems of aedes aegypti control in the americas. 19836626807
[diseases transmitted by mosquitoes and urbanization. examples of urban vectors of dengue and filariasis].once located in time and place the beginning of urbanization process, the mechanisms of adaptation to urban ecosystem and of dissemination by human conveyances are studied for two domestic mosquitoes: aedes aegypti and culex pipiens fatigans (= quinque-fasciatus). then epidemiological consequences are discussed. ae. aegypti pullulation constitutes a potential risk of urban yellow fever outbreak and the main factor of dengue haemorrhagic fever appearance; the increase of c. p. fatigans population ...19836627544
monoclonal antibodies against surface determinants on gametes of plasmodium gallinaceum block transmission of malaria parasites to mosquitoes.monoclonal antibodies (mab) against gametes of the chicken malaria plasmodium gallinaceum have been derived. all reacted with the surface of extracellular gametes of the parasite in immunofluorescent antibody reactions and all agglutinated both male and female gametes. in the absence of active complement one mu isotype mab, la 1-d5, mediated at least 95% suppression of infectivity of the parasites to aedes aegypti mosquitoes. individually, mab of the gamma 1 or gamma 2a isotypes mediated only sl ...19836631012
[action of the delta-endotoxin of bacillus thuringiensis var. israelensis on cultured cells from aedes aegypti l].the effects of bacillus thuringiensis var. israelensis delta-endotoxin were investigated on a cell culture of aedes aegypti with the electron microscope. the ultrastructural changes following intoxication were: disintegration of endoplasmic reticula by the formation of spherical structures; condensation and then swelling of mitochondria with disappearance of internal cristae; frequent dilatation of the perinuclear space; cellular lysis. the action of a metabolic inhibitor, 2,6-dibromophenol (2,6 ...19836638755
vertebrate host specificity and experimental vectors of plasmodium (novyella) kempi sp. n. from the eastern wild turkey in iowa.vertebrate host specificity, experimental laboratory vectors, and a description of plasmodium (novyella) kempi sp. n. from eastern wild turkeys (meleagris gallopavo silvestris vieillot) in iowa are presented. plasmodium kempi is infective for domestic turkeys, bobwhites (colinus virginianus), chukars (alectoris graeca), guinea fowl (numida meleagris), peacocks (pavo cristatus), and canaries (serinus canaria), produces a transient infection in mallards (anas platyrhynchos) and domestic geese (ans ...19836644918
transmission of dengue virus by orally infected aedes triseriatus.transmission of dengue type 1 was demonstrated for 3 strains of aedes triseriatus mosquitoes after oral infection. rates of infection were similar to those observed in a control strain of aedes aegypti. three additional species belonging to the subgenus protomacleaya (aedes brelandi, aedes hendersoni, and aedes zoosophus) were also susceptible to oral infection with dengue type 1 virus but transmission could not be demonstrated although virus was detected in the salivary glands of infected mosqu ...19836650743
a case study of aedes aegypti prevalence by settlement types in dehu town group of maharashtra state. 19836668009
linkage relationships of eleven enzyme loci in the aedes scutellaris group.linkage relationships of 11 enzyme loci were determined in backcrosses between aedes polynesiensis and aedes kesseli. three linkage groups established were aat2-lap2-me-sex, cat-ao-pgm-idh2-est6, and gpi-odh-pgd. lap2 and cat have not been previously mapped in aedes. locus order and linkage groups were the same as those observed for seven loci mapped in aedes aegypti. the significance of the observed similarities in chromosome organization and differences in crossover values among closely relate ...19836670992
susceptibility of aedes aegypti to infections with dirofilaria immitis and dirofilaria repens.eight stocks of aedes aegypti-4 geographic stocks and 4 selected stocks-were tested for their susceptibility to infection with dirofilaria immitis and d. repens. four of the stocks were found to be susceptible and the other 4 were refractory of infection with d. immitis. all the stocks of ae. aegypti that were susceptible to d. immitis were also susceptible to d. repens but the stocks that were refractory to d. immitis were all partially susceptible to d. repens.19836673132
characterization of antigens on mosquito midgut stages of plasmodium gallinaceum. i. zygote surface antigens.we have defined the surface protein antigens on plasmodium gallinaceum zygotes using radioiodination methods and rabbit anti-zygote serum which blocks transmission of the parasite to aedes aegypti mosquitoes. fifteen protein bands (1-15) in the molecular weight range of 40 000-240 000 and one band at the bromophenol blue dye marker were labelled by the lactoperoxidase and iodogen (1,3,4,6-tetrachloro-3 alpha,6 alpha-diphenylglycoluril) methods. the localization of these radioiodinated components ...19836683783
increased intradermal probing time in sporozoite-infected mosquitoes.because malaria sporozoites destroy segments of the salivary glands of vector mosquitoes, we determined whether salivary function is impaired. such pathology would result in a prolonged intradermal probing phase of feeding behavior, because the role of saliva is to help locate blood vessels. indeed, non-infected aedes aegypti mosquitoes probed for a shorter period than did either sporozoite-infected or saliva-deprived mosquitoes. salivary apyrase activity is reduced to a third following maturati ...19846696175
dengue fever. reappearance in northern queensland after 26 years.during march, 1981, a number of cases of dengue fever occurred in cairns and townsville, northern queensland. from october, 1981, an outbreak of the infection was recognized on thursday island and, by may 1982, an estimated 38% of residents had been infected. isolated cases were reported from other towns in northern queensland and from other islands in the torres strait. clinical presentation varied from that of severe incapacitating illness lasting up to seven days to infections which were conf ...19846700459
bioassay of solubilized bacillus thuringiensis var. israelensis crystals by attachment to latex beads.solubilized crystals of bacillus thuringiensis var. israelensis were 7000 times less toxic to aedes aegypti larvae than intact crystals, presumably because mosquito larvae are filter feeders and selectively concentrate particles while excluding water and soluble molecules. a procedure is described whereby soluble toxins are adsorbed to 0.8-micrometer latex beads, with retention of toxicity. the latex bead assay should make it possible to analyze the structure and mode of action of the mosquito t ...19846701520
a large transmissible plasmid is required for crystal toxin production in bacillus thuringiensis variety israelensis.bacillus thuringiensis var. israelensis (bti), serotype 14, which produces parasporal crystals toxic to certain dipteran larvae, was analyzed by agarose gel electrophoresis and found to contain a complex plasmid array. eight plasmids were detected, with approximate sizes of 3.3, 4.2, 4.9, 10.6, 68, 75, 105, and 135 mda, as well as a plasmidlike linear dna element of approximately 10 mda. partially cured mutants of bti implicated the 75-mda plasmid in crystal production. fifteen independently iso ...19846709732
the effect of humidity on the transmission of brugia pahangi infective larvae to mammalian hosts by aedes aegypti.the transmission of brugia pahangi by aedes aegypti to the mammalian host was compared at low and high humidity. there was no statistical difference between the number of infected mosquitoes feeding or the egress of infective larvae from these mosquitoes at high or low humidity. the penetration of the host by the infective larvae was however significantly greater (p less than 0.05) at high than at a low humidity.19846710572
plasmodium gallinaceum: erythrocyte factor essential for zygote infection of aedes aegypti.zygotes of plasmodium gallinaceum, fertilized in vitro and fed to aedes aegypti mosquitoes through a membrane, formed oocysts only when a substance in the cytoplasm of uninfected erythrocytes was present. the relation between erythrocyte volume and infectivity was linear (1:1.2) up to a 50% hematocrit. the intraerythrocytic substance was both nondialyzable and poorly soluble in plasma. by carboxymethyl cellulose chromatography, cytoplasmic constituents eluted at ph 8.6 supported the same infecti ...19846714357
[comparison of the flight capability of plasmodia-infected and plasmodia-free aedes aegypti]. 19846717377
the use of mosquitoes (aedes aegypti) to detect ciguatoxin in surgeon fishes (ctenochaetus striatus).a new animal assay to detect ciguatoxin in fishes was developed. mosquitoes were subjected to intrathoracic injection of serial dilutions of ciguatoxin crude extracts. toxicity of the fishes was expressed as the mosquito ld50 (g of flesh per mosquito). a significant correlation between the mosquito bioassay and the mouse bioassay performed on the same extracts was shown (r = 0.72, n = 80). we were able to detect 96% of the toxic fishes, while 91% of the fishes non-toxic in mice were also non-tox ...19846719474
a mosquito-virulent bacillus sphaericus in adult simulium damnosum from northern nigeria.from newly emerged adult simulium damnosum from kaduna river, northern nigeria, a mosquito-virulent strain of bacillus sphaericus was isolated. in another four cases non-virulent b. sphaericus were present. the isolate exerted a lc50 of 50 spores/ml for culex pipiens l4-larvae and was less virulent for anopheles stephensi (400 sp/ml) and aedes aegypti (800 sp/ml).19846720123
plasmodium gallinaceum: density dependent limits on infectivity to aedes acute, blood-induced infections of chickens, the malarial parasite plasmodium gallinaceum is most infective to the mosquito aedes aegypti 1 day before gametocyte numbers peak. in an effort to account for this disynchrony , daily changes in parasite infectivity, parasitemia, hematocrit, and hemoglobin were measured during the course of infections. three events were correlated with the loss of infectivity: (1) in the 24 hr between park infectivity and peak gametocytemia , schizont-induced hemol ...19846723894
[ecology of dengue and aedes aegypti. preliminary research. 2]. 19846729600
genetic heterogeneity among caribbean populations of aedes aegypti.using starch gel electrophoresis, we have analyzed genetic variation at 11 loci in 18 caribbean collections of aedes aegypti. our results show that, while there is some relationship between geographic proximity and genetic distance, the overall picture among islands is one of gene frequency patchiness , with some collections clearly not conforming to any geographic pattern. we attribute this to the combined effects of high rates of gene flow among islands and with the mainland american continent ...19846731681
experimental aerial spraying with ultra-low-volume (ulv) malathion to control aedes aegypti in buga, colombia. 19846733345
blood feeding affects age-related changes in the host-seeking behavior of aedes aegypti (diptera: culicidae) during oocyte maturation. 19846748001
nondevelopment of wuchereria bancrofti in nude (congenitally athymic) mice.infective larvae of wuchereria bancrofti (nematoda: filarioidea) were harvested from aedes aegypti mosquitoes fed in vitro on microfilaremic blood of haitian volunteers. larvae were inoculated either into the subcutaneous tissue (sc) or peritoneal cavity (ip) of congenitally athymic (nude) mice, c3h/hen (nu/nu). initially 15 male and two female mice received larval doses from 38-180, and necropsy was done between 11 and 75 days post-inoculation. no worms were found at necropsy. four additional m ...19826751107
comparative study of hemocytes and associated cells of some medically important dipterans.the aim of this work is to study, characterize, and compare different morphological types of hemocytes of glossina austeni, g. morsitans, calliphora erythrocephala, stomoxys calcitrans, lucilia sericata, aedes aegypti, and culex quinquefasciatus. this information is intended to provide a basis for future studies of the cellular defense mechanisms of these dipterans. seven morphological types of hemocytes were identified by phase-contrast optics: prohemocytes, plasmatocytes, thrombocytoids, granu ...19826764649
transovarial transmission of yellow fever virus in stegomyia mosquitoes.transovarial transmission of two strains of yellow fever virus was demonstrated in three colonized geographical strains of aedes aegypti following infection by intrathoracic inoculation. infected progeny were detected in f1 offspring from only the first three ovarian cycles (ovc). the overall minimum filial infection rate for the first three ovc was 1:596; rates were loser in the second and third ovc. virus survived in eggs for longer than 4 months and was recovered from progeny of three immersi ...19806766282
dengue-2 vaccine: viremia and immune responses in rhesus monkeys.studies were undertaken in indian rhesus monkeys (macaca mulatta) to determine the safety, potency, immunogenicity, and mosquito infectivity of a small-plaque, temperature-sensitive variant of dengue type 2 (den-2) virus, a vaccine candidate. fifteen monkeys were inoculated subcutaneously with the vaccine virus, ten receiving 10(3.1) plaque-forming units (pfu) and five receiving 10(4.5) pfu. after primary immunization, viremia was detected in only one monkey, a recipient of the higher dose of va ...19806766903
comparative susceptibility of sterilized and genetically-defined strains of aedes aegypti to dirofilaria repens. 19816798102
cryopreservation of the microfilariae of brugia malayi, dirofilaria corynodes, and wuchereria bancrofti.methods are presented for the cryopreservation of a sheathed microfilaria, brugia malayi, and an unsheathed species, dirofilaria corynodes. the former survived best when frozen at the rate of -0.8 degree or -0.5 degree c per minute using 9% dimethyl sulfoxide (dmso) as the cryopreservative. approximately 52-79% of the thawed microfilariae developed to the third stage in aedes aegypti mosquitoes versus 79% of the unfrozen specimens. for d. corynodes the optimum freezing rate was -2 degrees or -5 ...19836824119
epidemiologic investigations of dengue infection in mexico, 1980.a binational investigation was conducted in two mexican cities in 1980 to study epidemiologic characteristics of dengue. two study areas were selected in each of the cities (merida and tampico); in each area, in february and in september, sanitarians recorded information concerning abundance of aedes aegypti, and public health nurses obtained blood specimens and clinical information from residents. ninety-nine individuals (24% of the study population) showed serologic evidence of recent dengue 1 ...19836829561
plasmodium gallinaceum: avian screen for drugs with radical curative properties.existing primary screens for radical curative antimalarial drugs fail to adequately detect many compounds which affect the latent, exoerythrocytic hypnozoite, the stage of the parasite responsible for relapse. at the same time, these screens falsely identify a wide range of compounds with no radical curative activity. the avian malaria, plasmodium gallinaceum, and aedes aegypti mosquitos were used in a screen which measures the effects of candidate compounds on gametocytes and their development ...19836832279
larvicidal activity of bacillus thuringiensis subsp. israelensis, serovar h14 in aedes aegypti: histopathological studies. 19836841993
[repellent properties of mannich bases and cresol and phenol derivatives for aedes aegypti l. mosquitoes and the flea xenopsylla cheopis roths]. 19836843496
[effect of the larval density of aedes aegypti mosquitoes on their mortality as affected by bacillus thuringiensis berl. preparations]. 19836843501
transovarial transmission of dengue 2 virus by aedes aegypti in nature.dengue 2 virus was recovered from three of 123 pools of naturally infected aedes aegypti larvae (6,200 insects) collected from water containers in rangoon. the virus was also isolated from two of 76 pools (7,730 mosquitoes) of male ae. aegypti, collected as larvae and reared in the laboratory to adults. minimum field infection rates among these two groups of mosquitoes were 1:2,067 and 1:3,865, respectively. insect pools were inoculated into toxorhynchites splendens mosquitoes and dengue viral a ...19836859404
[action of crystals of bacillus thuringiensis var. israelensis on the midgut of aedes aegypti l. larvae, studied by electron microscopy].ingestion of bacillus thuringiensis var. israelensis crystals by aedes aegypti larvae is followed by midgut epithelium disruption. earliest ultrastructural changes consist of an enlargement of intra- and intercellular spaces in the basal region of the cell. endoplasmic reticula disintegrate by forming spherical structures which increase in size during intoxication. mitochondria are transformed at first into a condensed form, then become swollen with the disappearance of internal cristae. in the ...19836870088
toxicity of bacillus thuringiensis var. israelensis crystals to aedes aegypti larvae: carbonate reversal.the toxicity of purified bacillus thuringiensis var. israelensis crystals to larvae of aedes aegypti could be reversed 100-fold by levels of k(2)co(3) as low as 0.15%.19836870244
effect of trypsin and neuraminidase on the infectivity of plasmodium gallinaceum investigation was carried out to examine the effect of trypsin and neuraminidase on the infectivity of plasmodium gallinaceum sporozoites. the sporozoites were obtained from freshly dissected salivary glands of aedes aegypti: their infectivity was assayed by their ability to produce a patent parasitaemia following their inoculation into day-old chicks. infectivity was abolished by treatment of the sporozoites with trypsin at a concentration of 100 micrograms ml-1 for 30 minutes at 30 degrees ...19836882061
the regulation of preimaginal populations of aedes aegypti l. (diptera: culicidae) on the kenya coast. i. preimaginal population dynamics and the role of human behaviour.on the kenya coast aedes aegypti breeds in pots maintained indoors for water storage. pupal numbers vary greatly from one pot to another. the rhythm of water replenishment and the accidental introduction of food into the pots regulate pupal numbers. when water replenishment occurs more often than once per week, pupal numbers are small. when replenishment occurs less often, both low and high pupal numbers may be observed. the presence or absence of larval food distinguishes pots of high versus lo ...19836882066
production of bacillus sphaericus strain 1593 primary powder on media made from locally obtainable nigerian agricultural products.five media, formulated from dried cow blood, mineral salts, and seeds from four species of legumes, were assessed for growth, sporulation, and insecticidal properties of bacillus sphaericus strain 1593. bacterial powders, prepared from broth, were assayed against culex quinquefasciatus, anopheles gambiae, and aedes aegypti. good growth and sporulation were obtained with all the media. the highest number of viable cells and spores per mililitre (8.6 x 10(8) and 8.1 x 10(8] were obtained in media ...19836883226
macrogeographic genetic variation in a human commensal: aedes aegypti, the yellow fever mosquito. 19836884770
brugia pahangi: growth improvement with lecithin in the diet of axenically reared hosts, aedes aegypti. 19816894428
anti-gamete monoclonal antibodies synergistically block transmission of malaria by preventing fertilization in the mosquito.experiments from our laboratory previously demonstrated that infected chickens immunized with gametes of the avian malaria parasite plasmodium gallinaceum were no longer infectious to the mosquito vector aedes aegypti and that this transmission-blocking immunity was mediated by antibody. to identify those antigens that are the targets of transmission-blocking immunity, hybrid mouse cell lines secreting monospecific antibodies to surface antigens on male and female gametes of p. gallinaceum have ...19806935685
dengue haemorrhagic fever--a public health problem and a field for research.dengue haemorrhagic fever/dengue shock syndrome (dhf/dss) is an enigmatic and growing public health problem which is confined at present to countries of south-east asia. since 1956, over 350 000 patients have been hospitalized and nearly 12 000 deaths have been reported. dengue viruses, a group of four flaviviruses, are transmitted to man by aedes aegypti. currently, dengue viruses are actively transmitted in 61 countries which circle the globe in the tropical zone and have a combined population ...19806966540
scanning electron microscope study on larvae of wuchereria bancrofti from the vector and from experimental rodent hosts.the surface structures of larvae of wuchereria bancrofti from liberia were examined by scanning electron microscopy. for this study microfilariae from man, first-stage, second-stage, and third-stage larvae from the vector aedes aegypti, and fourth-stage larvae from the experimental rodent hosts mastomys natalensis and meriones unguiculatus were available. from these larvae the structure of the anterior ends, the cuticle in the midbody regions, and the posterior ends are presented. as an obvious ...19807003854
morphometric parameters of the midgut cells of aedes aegypti l. (insecta, diptera) under various conditions.previous morphometric or biochemical investigations have yielded different data on the distribution of free and membrane-bound ribosomes in midgut cells of aedes aegypti. in the present paper ribosomal distribution has been morphometrically analysed to determine whether different mosquito strains, different food and different narcosis used in these previous studies, and/or methodological errors, could account for the different results. most of the cellular parameters in the stomach epithelium of ...19817023689
morphogenesis of yellow fever virus in aedes aegypti cultured cells. i. isolation of different cellular clones and the study of their susceptibility to infection with the virus.we report the isolation of 19 cellular clones of aedes aegypti and analyze their susceptibility to infection with yellow fever virus, in comparison with the uncloned cells. four types of clones were found, different in their morphology, their metabolism and their virus production. the c 17 clone produces the most virus, not only with respect to the other aedes aegypti clones, but also to other uncloned arthropod cells published in the literature. a cytopathic effect exists in the virus infected ...19817025663
ultrastructural damage of in vitro cultured ookinetes of plasmodium gallinaceum (brumpt) by purified proteinases of susceptible aedes aegypti (l.).previous in vivo studies have implicated trypsin-like proteinases in the destruction of ookinetes of plasmodium gallinaceum in the gut of the susceptible mosquito aedes aegypti (gass 1977). an in vitro study has shown that the ookinetes are destroyed by crude extracts of blood-fed a. aegypti and that this destruction is largely inhibited by an inhibitor of mosquito proteinases, lima bean trypsin inhibitor (gass and yeates 1979). in the present study ookinetes of p. gallinaceum have been incubate ...19817034390
host behaviour and mosquito feeding success: an experimental study.the susceptibility of laboratory rabbits to attack by mosquitoes (aedes aegypti) is found to be closely linked to their grooming activity. prevention of grooming significantly increases both the percentage of mosquitoes feeding and the size of blood meals. grooming responses intensify with parasite density, and lead to a slight decline in parasite feeding success and blood meal size. grooming efficiency varied between individual rabbits and also a consequence of experience, with rabbits improvin ...19827080144
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