Background: Similar to other hematophagous insects, male and female sand flies must feed on plants to obtain sugar and, subsequently, energy to complete their life cycles. A large number of compounds emitted by plants may act as volatile signals to these insects. Primary alcohols have been detected in some plants, but in small amounts. In a previous report, the attractiveness of saturated primary alcohols with 7 to 9 carbons was evaluated for Lutzomyia longipalpis, the vector of American visceral leishmaniasis, with positive results. Methods: In the present study, a wide range of primary alcohols, 3 to 10 carbons, were tested to investigate their attractiveness to another sand fly species, Nyssomyia neivai, a putative vector of American cutaneous leishmaniasis. The mixture of compounds that induced the best sand fly response was also evaluated. Results: Of the eight compounds evaluated, hexanol and octanol elicited the best attractive responses for sand fly females. Conclusion: Phytochemicals may be an interesting source of search for new sand fly attractants.

BackgroundThe potential attraction from 1-octen-3-ol for sandflies has been documented; however, studies using other primary alcohols are limited.FindingsWe used a wind tunnel to compare the activation and attractive behaviors in male and female Lutzomyia longipalpis using 1-octen-3-ol and three additional alcohols, 1-octanol, 1-heptanol and 1-nonanol at three different concentrations: neat (100%) and diluted in hexane (10% and 50%). The compounds 1-octen-3-ol and 1-nonanol induced a clear concentration-dependent activation and attraction response in females. In males, 1-octen-3-ol, 1-nonanol and 1-heptanol yielded the same results.ConclusionsL. longipalpis is attracted to 1-octen-3-ol, 1-nonanol and 1-heptanol, which are found in many plant volatiles.

BackgroundThe most critical phase in sand fly colonization is the high mortality in the larval instars. In this study, we sought out strategies for improving the colonization of Nyssomyia neivai, one of the vectors of cutaneous leishmaniasis agent in South America.MethodsA colony of Ny. neivai was established in the laboratory from a field population, and the productivity of adults was evaluated considering carrying capacity, diet for larvae and surface for oviposition.ResultsThe highest emergency rate of adults was achieved with the fewest couples inside 150 mL rearing chambers on a sterilized diet made of rabbit feces, rabbit food, soil and fish food and with vermiculite as a substrate for oviposition and the development of larvae.ConclusionOur data on Ny. neivai colonization showed that the best adult productivities were achieved with fewer couples inside the rearing chambers; smaller rearing containers of 150 mL (due to less fungi growth); sterilized diet made of rabbit feces, rabbit food, soil and fish food; and vermiculite as the substrate for oviposition and development of larvae.

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Background Phlebotomine sand flies are vectors for several pathogens, with Leishmania being the most important. In Brazil, the main aetiological agent of American cutaneous leishmaniasis (ACL) is Leishmania (Viannia) braziliensis , and Nyssomyia neivai is one of its main vectors in São Paulo state and other areas of South America. Similar to other haematophagous insects, sand flies use volatile compounds called kairomones to locate their hosts for blood meals. A possible increase in the attractiveness of hosts infected with Leishmania infantum to their vectors has been demonstrated. In the present study, we aimed to investigate whether L . braziliensis -infected hosts present higher attractiveness to Ny . neivai and to identify differences in the volatile compounds released by infected and uninfected mice. Results Behavioural experiments in which sand fly females directly fed on infected or uninfected mice showed no significant differences in the attractiveness of the mice or the blood volume ingested. Y-tube olfactometer bioassays also revealed no significant differences in the attractiveness of these hosts to Ny . neivai . No differences were observed in the profiles of the volatile compounds released by the two groups of mice. However, PCA and cluster analysis were able to classify the 31 identified compounds into three clusters according to their abundances. This classification showed a possible role for individual variation in the absence of differences in volatile profiles and attractiveness between infected and uninfected mice. Conclusion In this first cross-sectional study with an aetiological agent of ACL, there were no statistically significant differences in the attractiveness of infected hosts to their vector.