Characterization of vector communities and biting behavior in South Sulawesi with host decoy traps and human landing catches

Background Indonesia has high mosquito diversity, with circulating malaria and arboviruses. Human landing catches (HLC) are ethically questionable where arboviral transmission occurs. The host decoy trap (HDT) is an exposure-free alternative outdoor sampling device. To determine HDT efficacy for local culicids, and to characterize local mosquito fauna, the trapping efficacy of the HDT was compared to that of HLCs in one peri-urban (Lakkang) and one rural (Pucak) village in Sulawesi, Indonesia. Results In Lakkang the outdoor HLCs collected significantly moreAnophelesper night (n = 22 +/- 9) than the HDT (n = 3 +/- 1), while the HDT collected a significantly greater nightly average ofCulexmosquitoes (n = 110 +/- 42), than the outdoor HLC (n = 15.1 +/- 6.0). In Pucak, there was no significant difference inAnophelescollected between trap types; however, the HDT collected significantly moreCulexmosquitoes than the outdoor HLC nightly average (n = 53 +/- 11vs14 +/- 3). Significantly higher proportions of blood-fed mosquitoes were found in outdoor HLC (n = 15 +/- 2%) compared to HDT (n = 2 +/- 0%). More blood-fed culicines were collected with outdoor HLC compared to the HDT, whileAnophelesblood-fed proportions did not differ. For the HDT, 52.6%, 36.8% and 10.5% of identified blood meals were on cow, human, and dog, respectively. Identified blood meals for outdoor HLCs were 91.9% human, 6.3% cow, and 0.9% each dog and cat. Mosquitoes from Pucak were tested for arboviruses, with oneCulexpool and oneArmigerespool positive for flavivirus, and oneAnophelespool positive for alphavirus. Conclusions The HDT collected the highest abundance of culicine specimens. Outdoor HLCs collected the highest abundance ofAnophelesspecimens. Although the HDT can attract a range of different Asian mosquito genera and species, it remains to be optimized forAnophelesin Asia. The high proportion of human blood meals in mosquitoes collected by outdoor HLCs raises concerns on the potential exposure risk to collectors using this methodology and highlights the importance of continuing to optimize a host-mimic trap such as the HDT.