Visceral Leishmaniasis (LV) is a serious illness and can be fatal when not diagnosed in time. In Brazil, it is transmitted by the bite of female small insects infected by protozoan parasites belonging to the genus Leishmania, and the main vector is the species Lutzomyia longipalpis (sand fly). For this reason, the Oswaldo Cruz Institute (IOC/Fiocruz) initiated the project “Field tests with synthetic sexual pheromone to reduce the transmission of visceral leishmaniasis by Lutzomyia longipalpis, with the support of Fiotec.

The infection of the female of these insects occurs at the moment when it feeds on the blood of infected vertebrate host animals. The success of this feeding is due to the strong attraction caused by the combination of the animal’s smell and the sexual pheromone produced by the phlebotomus males, who are attracted by them.

In other research carried out, it was possible to synthesize and produce great quantities of the pheromone in laboratory. When it is placed near to the host, for example, in a shelter of animals, the substance imitates the action of the male by attracting the females for sanguineous feeding, reinforced by the exhaled odor of the animals that attract the insects.

Therefore, the use of residual action insecticides is being studied to make the combat against these insects more efficient, since there would be a greater attraction of females to the place where the pheromone is released, serving both to attract, as well as to kill great quantities of insects of both sexes. In this study, it is intended to test, in the field, the strategy “attract and kill”, aiming the reduction of canine infection and the population density of Lutzomyia longipalpis, diminishing, as a consequence, VL in human beings.

Understand the disease

VL is a chronic, systemic disease, characterized by a fever of long duration, loss of weight, organic weakness, reduction of muscular force and anemia, among other symptoms. When not treated, it can lead to death in 90% of the cases.

According to the World Health Organization, it is estimated that 500 thousand new cases of VL occur annually, and that, 90% of these cases occurs in Bangladesh, Brazil, India, Nepal and the Sudan. It is noteworthy that of the cases registered in Latin America, 90% occur in Brazil.

It must be pointed out that only a small portion of infected individuals develop signals and symptoms of the disease. Children and the elderly are more susceptible to the infection.

*Data from the Ministry of Health are used