Search for: All records

BackgroundSugar feeding is an important behavior which may determine vector potential of female mosquitoes. Sugar meals can reduce blood feeding frequency, enhance survival, and decrease fecundity, as well as provide energetic reserves to fuel energy intensive behaviors such as mating and host seeking. Sugar feeding behavior can be harnessed for vector control (e.g. attractive toxic sugar baits). Few studies have addressed sugar feeding ofAedes albopictus, a vector of arboviruses of public health importance, including dengue and Zika viruses. To address this knowledge gap, we assessed sugar feeding patterns ofAe.albopictusfor the first time in its invasive northeastern USA range. Methodology/Principal findingsUsing the cold anthrone fructose assay with robust sample sizes, we demonstrated that a large percentage of both male (49.6%) and female (41.8%)Ae.albopictusfed on plant or homopteran derived sugar sources within 24 hrs prior to capture. Our results suggest that sugar feeding behavior increases when environmental conditions are dry (high saturation deficit) and may vary by behavioral status (host seeking vs. resting). Furthermore, mosquitoes collected on properties with flowers (>3 blooms) had higher fructose concentrations compared to those collected from properties with few to no flowers (0–3). Conclusions/SignificanceOur results provide the first evidence ofAe.albopictussugar feeding behavior in the Northeastern US and reveal relatively high rates of sugar feeding. These results suggest the potential success for regional deployment of toxic sugar baits. In addition, we demonstrate the impact of several environmental and mosquito parameters (saturation deficit, presence of flowers, host seeking status, and sex) on sugar feeding. Placing sugar feeding behavior in the context of these environmental and mosquito parameters provides further insight into spatiotemporal dynamics of feeding behavior forAe.albopictus, and in turn, provides information for evidence-based control decisions. 

Abstract Flowers can be transmission platforms for parasites that impact bee health, yet bees share floral resources with other pollinator taxa, such as flies, that may be hosts or non-host vectors (i.e., mechanical vectors) of parasites. Here, we assessed whether the fecal-orally transmitted gut parasite of bees,Crithidia bombi, can infectEristalis tenaxflower flies. We also investigated the potential for two confirmed solitary bee hosts ofC. bombi,Osmia lignariaandMegachile rotundata, as well as two flower fly species,Eristalis arbustorumandE. tenax,to transmit the parasite at flowers. We found thatC. bombidid not replicate (i.e., cause an active infection) inE. tenaxflies. However, 93% of inoculated flies defecated liveC. bombiin their first fecal event, and all contaminated fecal events containedC. bombiat concentrations sufficient to infect bumble bees. Flies and bees defecated inside the corolla (flower) more frequently than other plant locations, and flies defecated at volumes comparable to or greater than bees. Our results demonstrate thatEristalisflower flies are not hosts ofC. bombi, but they may be mechanical vectors of this parasite at flowers. Thus, flower flies may amplify or diluteC. bombiin bee communities, though current theoretical work suggests that unless present in large populations, the effects of mechanical vectors will be smaller than hosts.