Trichomonas vaginalis is identified as greatest public sexually transmitted disease

infected organs mainly liver and lungs and to some extent other organs including spleen, kidneys, heart, brain and bones of the animal carcasses. Prevention of cystic hydatid disease primarily focusing on veterinary investigations for controlling the extent and the intensity of echinococcosis in the definitive host populations, which indirectly may lead to control the prevalence of hydatid disease in the intermediate host animals. Treatment of cystic hydatidosis in livestock is still under investigation but anti-helminthes drugs can be used. Regular treatment, taking high degree of precautions when handling pets or dealing with animal meat must be taken into consideration to minimize the level of infection and egg excretion as well as the vaccination of ruminant intermediate hosts, are all in evaluation.

Bacillus thuringiensis subsp. israelensis is the most important biological insecticide for the control of mosquito vectors of disease. This bacterium produces toxins during sporulation that cause larval death by lysis of cells in their midgut. The pBtoxis plasmid of B. thuringiensis subsp. israelensis encodes all the mosquitocidal toxins and a number of other coding sequences. The plasmid also carries potential germination genes organised in a single ger operon. Comparison of the germination responses of spores from strains with and without pBtoxis revealed that this plasmid could promote activation of the spores under alkaline conditions but not following heat treatment. Introduction of the ger operon on a recombinant plasmid to the plasmidless strain established this operon as the first with an identified role in alkaline activation.

Differences in activation between spores from strains of Bacillus thuringiensis subsp. israelensis with and without the toxin-encoding plasmid pBtoxis are demonstrated. Following alkaline activation, the strain bearing pBtoxis shows a significantly greater germination rate. Expression of just three genes constituting a previously identified, putative ger operon from this plasmid is sufficient to produce the same phenotype and characterizes this operon as a genetic determinant of alkaline activation.