Esperanza Window Traps for the collection of anthropophilic blackflies (Diptera: Simuliidae) in Uganda and Tanzania.

There is an increasing need to evaluate the impact of chemotherapeutic and vector-based interventions as onchocerciasis affected countries work towards eliminating the disease. The Esperanza Window Trap (EWT) provides a possible alternative to human landing collections (HLCs) for the collection of anthropophilic blackflies, yet it is not known whether current designs will prove effective for onchocerciasis vectors throughout sub-Saharan Africa. EWTs were deployed for 41 days in northern Uganda and south eastern Tanzania where different Simulium damnosum sibling species are responsible for disease transmission. The relative efficacy of EWTs and HLCs was compared, and responses of host-seeking blackflies to odour baits, colours, and yeast-produced CO2 were investigated. Blue EWTs baited with CO2 and worn socks collected 42.3% (2,393) of the total S. damnosum s.l. catch in northern Uganda. Numbers were comparable with those collected by HLCs (32.1%, 1,817), and higher than those collected on traps baited with CO2 and BG-Lure (25.6%, 1,446), a synthetic human attractant. Traps performed less well for the collection of S. damnosum s.l. in Tanzania where HLCs (72.5%, 2,432) consistently outperformed both blue (16.8%, 563) and black (10.7%, 360) traps baited with CO2 and worn socks. HLCs (72.3%, 361) also outperformed sock-baited (6.4%, 32) and BG-Lure-baited (21.2%, 106) traps for the collection of anthropophilic Simulium bovis in northern Uganda. Contrasting blackfly distributions were observed on traps in Uganda and Tanzania, indicating differences in behaviour in each area. The success of EWT collections of S. damnosum s.l. in northern Uganda was not replicated in Tanzania, or for the collection of anthropophilic S. bovis. Further research to improve the understanding of behavioural responses of vector sibling species to traps and their attractants should be encouraged

Esperanza Window Traps for the collection of anthropophilic blackflies (Diptera: Simuliidae) in Uganda and Tanzania. S1 Table. Trap data.

Trap data associated with a paper titled "Esperanza Window Traps for the collection of anthropophilic blackflies (Diptera: Simuliidae) in Uganda and Tanzania" This dataset is made available as a Microsoft Excel file and hosted in the Figshare repository

Esperanza Window Traps for the collection of anthropophilic blackflies (Diptera: Simuliidae) in Uganda and Tanzania

There is an increasing need to evaluate the impact of chemotherapeutic and vector-based interventions as onchocerciasis affected countries work towards eliminating the disease. The Esperanza Window Trap (EWT) provides a possible alternative to human landing collections (HLCs) for the collection of anthropophilic blackflies, yet it is not known whether current designs will prove effective for onchocerciasis vectors throughout sub-Saharan Africa. EWTs were deployed for 41 days in northern Uganda and south eastern Tanzania where different Simulium damnosum sibling species are responsible for disease transmission. The relative efficacy of EWTs and HLCs was compared, and responses of host-seeking blackflies to odour baits, colours, and yeast-produced CO2 were investigated. Blue EWTs baited with CO2 and worn socks collected 42.3% (2,393) of the total S. damnosum s.l. catch in northern Uganda. Numbers were comparable with those collected by HLCs (32.1%, 1,817), and higher than those collected on traps baited with CO2 and BG-Lure (25.6%, 1,446), a synthetic human attractant. Traps performed less well for the collection of S. damnosum s.l. in Tanzania where HLCs (72.5%, 2,432) consistently outperformed both blue (16.8%, 563) and black (10.7%, 360) traps baited with CO2 and worn socks. HLCs (72.3%, 361) also outperformed sock-baited (6.4%, 32) and BG-Lure-baited (21.2%, 106) traps for the collection of anthropophilic Simulium bovis in northern Uganda. Contrasting blackfly distributions were observed on traps in Uganda and Tanzania, indicating differences in behaviour in each area. The success of EWT collections of S. damnosum s.l. in northern Uganda was not replicated in Tanzania, or for the collection of anthropophilic S. bovis. Further research to improve the understanding of behavioural responses of vector sibling species to traps and their attractants should be encouraged

Blackfly collection locations and distance from nearest known breeding sites.

<p>Alt. = Altitude, Dist. = Distance.</p

Summary data showing blackfly distribution on rows and columns of traps, including mean daily catch and standard errors (SE).

<p>Summary data showing blackfly distribution on rows and columns of traps, including mean daily catch and standard errors (SE).</p

Heat maps illustrating distribution of all blackfly specimens collected on EWTs in Tanzania (EWT Blue and EWT Black) and Uganda (EWT CO₂+ and EWT CO₂-) in 2016.

<p>Heat maps illustrating distribution of all blackfly specimens collected on EWTs in Tanzania (EWT Blue and EWT Black) and Uganda (EWT CO₂+ and EWT CO₂-) in 2016.</p

Median values and interquartile ranges of daily <i>S</i>. <i>damnosum</i> s.l. and <i>S</i>. <i>bovis</i> collections made using EWTs and HLCs.

<p>(A) <i>S</i>. <i>damnosum</i> s.l. collections made using BG-Lure and sock-baited EWTs in northern Uganda, 2015 (B) <i>S</i>. <i>bovis</i> collections made using BG-Lure and sock-baited EWTs in northern Uganda, 2015 (C) <i>S</i>. <i>damnosum</i> s.l. collections made using black and blue EWTs in Tanzania, 2016 (D) <i>S</i>. <i>damnosum</i> s.l. collections made using fresh (CO₂+) and pre-prepared (CO₂-) sugar-yeast sources of CO₂ in northern Uganda, 2016.</p

Summary data showing number of blackflies of each species collected using all methods.

<p>Summary data showing number of blackflies of each species collected using all methods.</p

Biting flies other than blackflies removed from traps in Tanzania and Uganda, 2016.

<p>Biting flies other than blackflies removed from traps in Tanzania and Uganda, 2016.</p

Summary data of <i>S</i>. <i>damnosum</i> s.l. and <i>S</i>. <i>bovis</i> collections for each trap type.

<p>Summary data of <i>S</i>. <i>damnosum</i> s.l. and <i>S</i>. <i>bovis</i> collections for each trap type.</p