Susceptibility of bacillus thuringiensis-treated anopheles stephensi and anopheles gambiae to infection with plasmodium cynomolgi

An. Stephensi and An. Gambiae were treated as larvae with B. thuringiensis israelensis and then fed on monkeys infected with the malaria parasite, P. cynomolgi. The susceptibility of the mosquitos to P. Cynomolgi was evaluated by the presence of oocysts on the wall of the stomach. The data showed that the bacterial toxins did not consistently affect the susceptibility of the mosquitos to several strains of P. cynomolgi

effect of bacillus thuringiensis strain H-14 and bacillus sphaericus isolate 1593-4 on the fecundity and longevity of anopheles stephensi

The effect of 4th instar larval exposure to the bacterial larvicides of B. Thuringiensis H-14 and B. sphaericus [1593-4] on the fecundity and longevity of adults survived larval treatment was investigated. Results revealed a non-significant effect of B. Thuringiensis treatment on both fecundity and longevity. However, longevity was decreased due to larval exposure to B. Sphaericus, while, this bacterium has no effect on fecundity

Comparative toxicity of bacillus thuringiensis H14 and bacillus sphaericus, against culex pipiens and aedes caspius larvae

Thuringiensis fractions included two non-toxic fractions [136.000 and 38.000 dalton], two toxic non-specific fractions [68.000 and 25.000 dalton], and two toxic specific fractions for only Ae. Caspius [47.000 and 30.000 dalton]. Fractions of B. Sphaericus include three non-toxic fractions [75.000, 50.000 and 43.000 dalton], two showed very low toxicity with specificity to only Cx. pipiens [134.000 and 70.000 dalton] and two highly toxic fractions with specificity to Cx. pipiens [37.000 and 25.000]

Evidence of a biological mode of transmission of enteric bacteria by musca domestica sorbens

Groups of the house fly, Musca domestica sorbens, were fed on sugary solution contaminated with an aflagellated strain of Escherichia coli. Multiplication of this pathogen was detected during one week after the ingestion of E. coli, contaminated food. Bacterial propagation in the fly gut was found to be accompanied by a change of the aflagellated E. coli to the flagellated form. The gaining of flagellae during incubation in the fly gut was found to be stable even after being ingested again by another group of flies. Propagation of E. coli in the fly gut as well as flagellation development could indicate a biological means of transmission of enteric bacteria by M. domestica sorbens

Experimental contamination of musca domestica sorbens in relation to external and gut pathogen transmission

The house fly Musca domestica was tested as a vector transmitting the enteric bacterial pathogens as represented by a standard E. coli strain. The vetorial capacity of the house-fly was estimated as a mechanical transmitter on different external sites as well as for its transmission of the ingested bacteria through feeding behaviour. The achieved results revealed high external contamination densities of the mouth parts followed by the abdomen surface, legs and then wings. A marked increase of the ingested E. coli counts during one week after the ingestion of E. coli contaminated food indicate the propagation of the tested bacterium in the fly gut