Sikulu-Lord Maggy T, Milali Masabho P, Henry Michael, Wirtz Robert A, Hugo Leon E, Dowell Floyd E, Devine Gregor J
Mosquito Control Laboratory, QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia.
Environmental Health and Ecological Sciences Thematic Group, Ifakara Health Institute, Ifakara, United Republic of Tanzania.
PLoS Negl Trop Dis. 2016 Oct 21;10(10):e0005040. doi: 10.1371/journal.pntd.0005040. eCollection 2016 Oct.
Estimating the age distribution of mosquito populations is crucial for assessing their capacity to transmit disease and for evaluating the efficacy of available vector control programs. This study reports on the capacity of the near-infrared spectroscopy (NIRS) technique to rapidly predict the ages of the principal dengue and Zika vector, Aedes aegypti. The age of wild-type males and females, and males and females infected with wMel and wMelPop strains of Wolbachia pipientis were characterized using this method. Calibrations were developed using spectra collected from their heads and thoraces using partial least squares (PLS) regression. A highly significant correlation was found between the true and predicted ages of mosquitoes. The coefficients of determination for wild-type females and males across all age groups were R2 = 0.84 and 0.78, respectively. The coefficients of determination for the age of wMel and wMelPop infected females were 0.71 and 0.80, respectively (P< 0.001 in both instances). The age of wild-type female Ae. aegypti could be identified as < or ≥ 8 days old with an accuracy of 91% (N = 501), whereas female Ae. aegypti infected with wMel and wMelPop were differentiated into the two age groups with an accuracy of 83% (N = 284) and 78% (N = 229), respectively. Our results also indicate NIRS can distinguish between young and old male wild-type, wMel and wMelPop infected Ae. aegypti with accuracies of 87% (N = 253), 83% (N = 277) and 78% (N = 234), respectively. We have demonstrated the potential of NIRS as a predictor of the age of female and male wild-type and Wolbachia infected Ae. aegypti mosquitoes under laboratory conditions. After field validation, the tool has the potential to offer a cheap and rapid alternative for surveillance of dengue and Zika vector control programs.
估计蚊虫种群的年龄分布对于评估其传播疾病的能力以及评估现有病媒控制项目的效果至关重要。本研究报告了近红外光谱（NIRS）技术快速预测主要登革热和寨卡病毒病病媒埃及伊蚊年龄的能力。使用该方法对野生型雌雄埃及伊蚊以及感染了嗜菌异小杆线虫wMel和wMelPop菌株的雌雄埃及伊蚊的年龄进行了表征。利用偏最小二乘（PLS）回归，根据从其头部和胸部收集的光谱建立了校准模型。在蚊子的实际年龄和预测年龄之间发现了高度显著的相关性。所有年龄组野生型雌蚊和雄蚊的决定系数分别为R2 = 0.84和0.78。感染wMel和wMelPop的雌蚊年龄的决定系数分别为0.71和0.80（两种情况下P均< 0.001）。野生型埃及伊蚊雌蚊的年龄可以准确识别为< 8天龄或≥ 8天龄，准确率为91%（N = 501），而感染wMel和wMelPop的埃及伊蚊雌蚊分别以83%（N = 284）和78%（N = 229）的准确率被分为两个年龄组。我们的结果还表明，NIRS能够分别以87%（N = 253）、83%（N = 277）和78%（N = 234）的准确率区分野生型、感染wMel和wMelPop的年轻和年老雄蚊。我们已经证明了NIRS在实验室条件下作为野生型和感染沃尔巴克氏体的雌雄埃及伊蚊年龄预测指标的潜力。经过现场验证后，该工具有可能为登革热和寨卡病毒病病媒控制项目的监测提供一种廉价且快速的替代方法。
