The effect of luminous intensity on the attraction of phlebotomine sand flies to light traps

Abstract

To improve the efficiency of light traps in collecting phlebotomine sand flies, the potential effects of luminous intensity on the attraction of these insects to traps were evaluated. Sand flies were collected with Hooper Pugedo (HP) light traps fitted with 5-mm light-emitting diodes (LED) bulbs: green (520 nm wavelength-10,000, 15,000 and 20,000 millicandela (mcd) and blue (470 nm-4,000, 12,000 and 15,000 mcd). A total of 3,264 sand flies comprising 13 species were collected. The collected species were Lutzomyia longipalpis (Lutz & Neiva) (Diptera: Psychodidae) (52.48%), Evandromyia evandroi (Costa Lima & Antunes, 1939) (Diptera: Psychodidae) (32.90%) and Micropygomyia goiana (Martins, Falcão, & Silva) (Diptera: Psychodidae) (9.76%). An increase in luminous intensity of the LEDs increased the size of the sand fly catch. The lower luminous intensity of green (10,000 mcd) attracted an average of 13.7 ± 2.8 sand flies/trap per night and the other luminous intensities accounted for a mean of 24.1 ± 4.0 (15,000 mcd) and 28.2 ± 5.0 (20,000 mcd) sand flies/trap per night. Regarding the blue wavelength, the lower luminous intensity (4,000 mcd) attracted an average of 27.4 ± 4.1 sand flies/trap per night, followed by 12,000 mcd (37.6 ± 8.7) and 15,000 mcd (40.5 ± 7.3). Based on our data, the luminous intensity of light traps should be considered when developing light traps for monitoring or controlling phlebotomine sand flies.

Artificial light and biting flies: the parallel development of attractive light traps and unattractive domestic lights

“…More research is also needed on aspects of light attraction not discussed in this review, such as light height [113,114], light polarisation [115], time of day effects [40] and the presence of reflective surfaces [72]. Finally, future studies should control for thermal emissions, due to the attractiveness of IR light, as well as intensity, as its effects may not be consistent across wavelengths [64,76,78].…”

“…In one study, a blue (470 nm) LED attracted a higher number of Anopheles mosquitoes than a green (520 nm) LED of equal luminous intensity [76], but increasing the intensity of the green LED had a larger effect on Anopheles catches than increasing the intensity of the blue. Similarly, a blue (470 nm) LED was found to be more attractive than the equivalent green (520 nm) LED to sand flies, yet increasing luminous intensity significantly increased sand fly catches with the green LED but not the blue LED [78]. Finally, in choice-chamber experiments, when all the lights were at a low intensity, slightly more Lutzomyia longipalpis sand flies were attracted to blue-green (490-546 nm) wavelengths than they were the UV (350 nm) wavelength.…”

“…Traps using more powerful lights tend to catch more mosquitoes, midges and sand flies than those using dimmer ones [46,49,71,[74][75][76], and increasing the intensity of a given wavelength will generally increase the attractiveness of the light [18,[76][77][78]. Two studies have suggested an upper threshold of intensity above which biting fly catches either reach an asymptote [18] or begin to decrease [77]-although such a threshold requires corroboration.…”

Trypanosomatid infections in captive wild mammals and potential vectors at the Brasilia Zoo, Federal District, Brazil

“…felines’ units), making it difficult for sandflies to access the light trap, since these insects generally fly less than 200 meters and are close to food sources. The sampling could have been complemented by other traps like Disney, oily leaves, Falcon and light traps fitted with light‐emitting diode bulbs, which could improve the efficiency of phlebotomine trapping (Lima‐Neto et al, ). Moreover, low phlebotomine density could be explained by seasonal variation; e.g., the abundance of Lu.…”

Comparison of sand fly trapping approaches for vector surveillance of Leishmania and Bartonella species in ecologically distinct, endemic regions of Peru

“…incandescent lamp with blue, green, or red LED color bulbs [31,42]. All luminous traps were placed approximately one meter above ground level and operated overnight from 1800 to 0600 hours.…”