Comparison of the Trapping Efficacy of Locally Modified Gravid <i>Aedes</i> Trap and Autocidal Gravid Ovitrap for the Monitoring and Surveillance of <i>Aedes aegypti</i> Mosquitoes in Tanzania

• Published in: Insects
• Main Authors: Jane Johnson Machange, Masudi Suleiman Maasayi, John Mundi, Jason Moore, Joseph Barnabas Muganga, Olukayode G. Odufuwa, Sarah J. Moore, Frank Chelestino Tenywa
• Format: Article
• Language: English
• Published: MDPI AG 2024-05-01
• Subjects: <i>Aedes aegypti</i>; mosquito traps; vector control; Biogent Sentinel trap; Gravid <i>Aedes</i> Trap; autocidal gravid ovitrap
• Online Access: https://www.mdpi.com/2075-4450/15/6/401

The study assessed the trapping efficacy of locally modified (1) Gravid Aedes Trap (GAT) lined with insecticide-treated net (ITN) as a killing agent and (2) Autocidal Gravid Ovitrap (AGO) with sticky board in the semi-field system (SFS) and field setting. Fully balanced Latin square experiments were conducted to compare GAT lined with ITN vs. AGO, both with either yeast or grass infusion. Biogent-Sentinel (BGS) with BG-Lure and no CO₂ was used as a standard trap for <i>Aedes</i> mosquitoes. In the SFS, GAT outperformed AGO in collecting both nulliparous (65% vs. 49%, OR = 2.22, [95% CI: 1.89–2.60], <i>p</i> < 0.001) and gravid mosquitoes (73% vs. 64%, OR = 1.67, [95% CI: 1.41–1.97], <i>p</i> < 0.001). Similar differences were observed in the field. Yeast and grass infusion did not significantly differ in trapping gravid mosquitoes (OR = 0.91, [95% CI: 0.77–1.07], <i>p</i> = 0.250). The use of ITN improved mosquito recapture from 11% to 70% in the SFS. The same trend was observed in the field. Yeast was chosen for further evaluation in the optimized GAT due to its convenience and bifenthrin net for its resistance management properties. Mosquito density was collected when using 4× GATs relative to BGS-captured gravid mosquitoes 64 vs. 58 (IRR = 0.82, [95% CI: 0.35–1.95], <i>p</i> = 0.658) and showed no density dependence. Deployment of multiple yeast-baited GAT lined with bifenthrin net is cost-effective (single GAT < $8) compared to other traps such as BGS ($160).