Department of Zoology and Entomology, University of Pretoria, Hatfield, Pretoria, South Africa.
Department of Veterinary Services, Tsetse and Trypanosomiasis Control Unit, Ministry of Fisheries and Livestock, Lusaka, Zambia.
PLoS Negl Trop Dis. 2023 Jul 27;17(7):e0011512. doi: 10.1371/journal.pntd.0011512. eCollection 2023 Jul.
Tsetse-transmitted African trypanosomiasis is a debilitating and fatal disease of humans and livestock if left untreated. While knowledge of the spatial distribution patterns of tsetse is essential for the development of risk-based vector control strategies, existing distribution maps in Zambia are more than 40 years old and were based on coarse spatial resolution data. The recently developed vehicle-mounted sticky trap (VST) provides an alternative sampling device to aid in updating existing distribution maps but has not been applied outside an experimental setting and is limited to motorable tracks. Therefore, the objective of the present study was to demonstrate the effectiveness of utilizing the VST for area-wide surveys of Glossina morsitans and to use the occurrence records to predict its spatial distribution in Zambia under current environmental conditions using Maxent.
METHODOLOGY/PRINCIPAL FINDINGS: Two-sided all-blue VST baited with butanone and 1-octen-3-ol was used to survey 692 and 1020 km of transect routes in G. m. centralis Machado and G. m. morsitans Westwood previously published distribution in Zambia. Maxent species distribution technique was used to predict the potential distribution of the two subspecies using current climatic and environmental data which was then compared to the historical distribution. A total of 15,602 tsetse were captured with G. m. morsitans (58%) being the most abundant. G. m. centralis and G. pallidipes Austin represented 39 and 2% of the catch respectively, and G. brevipalpis Newstead was also detected. The predicted potential distribution for G. m. centralis was 80,863 km2 while that of G. m. morsitans was 70,490 km2 representing a 47 and 29% reduction compared to their historical distributions, respectively.
CONCLUSION/SIGNIFICANCE: The VST is effective for sampling G. morsitans outside experimental settings and is recommended for use as an additional tsetse survey tool. The spatial distribution of G. morsitans in Zambia has reduced by 101,051 km2 due to temperature and land cover changes.
如果不加治疗，采采蝇传播的非洲锥虫病会使人类和牲畜衰弱和致命。虽然了解采采蝇的空间分布模式对于制定基于风险的媒介控制策略至关重要，但赞比亚现有的分布地图已有 40 多年的历史，并且基于粗糙的空间分辨率数据。最近开发的车载粘性陷阱（VST）提供了一种替代采样设备，有助于更新现有的分布地图，但尚未在实验环境之外应用，并且仅限于可行驶的轨道。因此，本研究的目的是展示利用 VST 对 Glossina morsitans 进行大面积调查的有效性，并利用发生记录，在当前环境条件下使用 Maxent 预测其在赞比亚的空间分布。
方法/主要发现：使用双面全蓝色 VST 对巴西中部和西部的 Glossina morsitans Westwood 之前发表的分布区进行了 692 和 1020 公里的截线调查，诱饵为丁酮和 1-辛烯-3-醇。使用 Maxent 物种分布技术，利用当前的气候和环境数据预测两个亚种的潜在分布，然后将其与历史分布进行比较。共捕获 15602 只采采蝇，其中 G. m. morsitans（58%）最为丰富。G. m. centralis 和 G. pallidipes Austin 分别占捕获量的 39%和 2%，还检测到 G. brevipalpis Newstead。G. m. centralis 的预测潜在分布为 80863 km2，而 G. m. morsitans 的预测潜在分布为 70490 km2，分别比其历史分布减少了 47%和 29%。
结论/意义：VST 在外层空间环境中对 G. morsitans 进行采样是有效的，建议将其作为额外的采采蝇调查工具使用。由于温度和土地覆盖的变化，赞比亚 G. morsitans 的空间分布减少了 101051 km2。
