DEET 仍然是防止蚊虫叮咬的黄金标准，主要因为蚊子通常厌恶它的气味，尽管其确切机制仍有争议。问题是，一些蚊子似乎能够克服这种厌恶，引发了它们是否正在习惯这种化学物质的猜测。

图尔大学的 Claudio Lazzari 借鉴 19 世纪末巴甫洛夫的条件反射实验，测试饥饿蚊子是否会把 DEET 与食物联系起来。一组蚊子在暴露于普通空气或吹过浸有 DEET 纸张的空气时获得温热羊血，另一组则以糖水替代血液。

条件训练显著改变了行为：接触 DEET 同时获得血液或糖水的蚊子中有 60% 飞向并叮咬喷有驱蚊剂的手，而用普通空气训练的蚊子全部避开了 DEET。这个比例相当于每 5 只中有 3 只接受 DEET，而对照组为 0%，显示当现实中 DEET 因出汗或用量不足而减弱时，蚊子可能把微弱气味与进食联系起来，并在之后变得更危险。

DEET remains the gold standard for preventing mosquito bites, largely because mosquitoes usually find its smell unpleasant, even though the exact mechanism is still debated. The concern is that some mosquitoes appear able to overcome this aversion, raising the possibility that they are becoming accustomed to the chemical.

Claudio Lazzari of the University of Tours adapted Pavlov’s conditioning experiments from the late 1800s to test whether hungry mosquitoes could learn to associate DEET with food. One group received warm sheep’s blood while exposed either to ordinary air or to air blown past DEET-soaked paper, and a separate group repeated the setup with sugar water instead of blood.

Conditioning sharply changed behavior: 60% of mosquitoes exposed to DEET while receiving blood or sugar water flew to and bit a repellent-coated hand, whereas all mosquitoes trained with ordinary air avoided DEET. That contrast, three in five versus zero, suggests that when real-world DEET protection weakens through sweat or under-application, mosquitoes may link the faint odor with feeding and become more dangerous later.

Source: Mosquitoes seem to be getting over insect repellent

Subtitle: They learn to associate it with food

Dateline: 5月 28, 2026 06:39 上午